Merge remote-tracking branch 'upstream/master'

This grants the application the additional freedom to inherit from
different classes while still retaining the methods provided by
`Kemal::Handler`.

Should be fully backwards compatible as `Kemal::Handler` includes the
new module, with the class vars being defined in an `included` macro.

.ameba.yml

@@ -1,24 +0,0 @@
-# This configuration file was generated by `ameba --gen-config`
-# on 2023-01-30 12:35:15 UTC using Ameba version 1.4.0.
-# The point is for the user to remove these configuration records
-# one by one as the reported problems are removed from the code base.
-
-# Problems found: 2
-# Run `ameba --only Lint/UselessAssign` for details
-Lint/UselessAssign:
-  Description: Disallows useless variable assignments
-  Excluded:
-  - spec/view_spec.cr
-  Enabled: true
-  Severity: Warning
-
-# Problems found: 6
-# Run `ameba --only Lint/NotNil` for details
-Lint/NotNil:
-  Description: Identifies usage of `not_nil!` calls
-  Excluded:
-  - src/kemal/param_parser.cr
-  - src/kemal/static_file_handler.cr
-  - src/kemal/config.cr
-  Enabled: true
-  Severity: Warning

.github/workflows/ameba.yml

@@ -0,0 +1,19 @@
+name: Ameba
+
+on:
+  push:
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Download source
+        uses: actions/checkout@v6
+
+      - name: Run Ameba Linter
+        uses: crystal-ameba/github-action@master

.github/workflows/ci.yml

@@ -30,47 +30,3 @@ jobs:
       - name: Run specs
         run: |
           crystal spec
-
-  format:
-    strategy:
-      fail-fast: false
-      matrix:
-        os: [ubuntu-latest]
-        crystal: [latest, nightly]
-    runs-on: ${{ matrix.os }}
-
-    steps:
-      - name: Install Crystal
-        uses: crystal-lang/install-crystal@v1
-        with:
-          crystal: ${{ matrix.crystal }}
-
-      - name: Download source
-        uses: actions/checkout@v4
-
-      - name: Check formatting
-        run: crystal tool format --check
-    
-  ameba:
-    strategy:
-      fail-fast: false
-      matrix:
-        os: [ubuntu-latest]
-        crystal: [latest]
-    runs-on: ${{ matrix.os }}
-
-    steps:
-      - name: Install Crystal
-        uses: crystal-lang/install-crystal@v1
-        with:
-          crystal: ${{ matrix.crystal }}
-
-      - name: Download source
-        uses: actions/checkout@v4
-
-      - name: Install dependencies
-        run: shards install
-
-      - name: Run ameba linter
-        run: bin/ameba
-        

CHANGELOG.md

@@ -1,3 +1,156 @@
+# 1.10.1 (24-03-2026)
+
+- Add `shutdown_timeout` configuration for graceful shutdown: after `Kemal.stop`, Kemal can wait before exit so in-flight work can finish [#745](https://github.com/kemalcr/kemal/pull/745). Thanks @sdogruyol :pray:
+
+```crystal
+Kemal.config.shutdown_timeout = 10.seconds
+```
+
+# 1.10.0 (03-03-2026)
+
+- Add modular `Kemal::Router` with namespaced routing, scoped filters, WebSocket support and flexible mounting while keeping the existing DSL fully compatible [#731](https://github.com/kemalcr/kemal/pull/731). Thanks @sdogruyol :pray:
+
+```crystal
+require "kemal"
+
+api = Kemal::Router.new
+
+api.namespace "/users" do
+  get "/" do |env|
+    env.json({users: ["alice", "bob"]})
+  end
+
+  get "/:id" do |env|
+    env.text "user #{env.params.url["id"]}"
+  end
+end
+
+mount "/api/v1", api
+
+Kemal.run
+```
+
+- Add `use` keyword for registering global and path-specific middleware, including support for arrays and insertion at a specific position in the handler chain [#734](https://github.com/kemalcr/kemal/pull/734). Thanks @sdogruyol :pray:
+
+```crystal
+require "kemal"
+
+# Path-specific middlewares for /api routes
+use "/api", [CORSHandler.new, AuthHandler.new]
+
+get "/" do
+  "Public home"
+end
+
+get "/api/users" do |env|
+  env.json({users: ["alice", "bob"]})
+end
+
+Kemal.run
+```
+
+- Enhance response helpers to provide chainable JSON/HTML/text/XML helpers, `HTTP::Status` support and the ability to halt execution from a chained response for concise API error handling [#733](https://github.com/kemalcr/kemal/pull/733), [#735](https://github.com/kemalcr/kemal/pull/735), [#736](https://github.com/kemalcr/kemal/pull/736). Thanks @sdogruyol and @mamantoha :pray:
+
+```crystal
+require "kemal"
+
+get "/users" do |env|
+  # Default JSON response
+  env.json({users: ["alice", "bob"]})
+end
+
+post "/users" do |env|
+  # Symbol-based HTTP::Status and chained JSON
+  env.status(:created).json({id: 1, created: true})
+end
+
+get "/admin" do |env|
+  # Halt immediately with HTML response
+  halt env.status(403).html("<h1>Forbidden</h1>")
+end
+
+get "/api/users" do |env|
+  # Custom content type (JSON:API)
+  env.json({data: ["alice", "bob"]}, content_type: "application/vnd.api+json")
+end
+
+Kemal.run
+```
+
+- Ensure global wildcard filters always execute while keeping namespace filters isolated to their routes [#737](https://github.com/kemalcr/kemal/pull/737). Thanks @mamantoha :pray:
+- Fix CLI SSL validation and expand CLI option parsing specs [#738](https://github.com/kemalcr/kemal/pull/738). Thanks @sdogruyol :pray:
+- Make route LRU cache concurrency-safe with Mutex [#739](https://github.com/kemalcr/kemal/pull/739). Thanks @sdogruyol :pray:
+- Add `raw_body` to ParamParser for multi-handler body access (e.g. kemal-session) [#740](https://github.com/kemalcr/kemal/pull/740). Thanks @sdogruyol :pray:
+
+```crystal
+post "/" do |env|
+  raw = env.params.raw_body  # raw body, multiple handlers can call it
+  env.params.body["name"]    # parsed body
+end
+```
+
+- Fix OverrideMethodHandler route cache bug when using `_method` override [#741](https://github.com/kemalcr/kemal/pull/741), [#742](https://github.com/kemalcr/kemal/pull/742). Thanks @skojin and @sdogruyol :pray:
+
+# 1.9.0 (28-01-2026)
+
+- Crystal 1.19.0 support :tada:
+- ***(SECURITY)*** Limit maximum request body size to avoid DoS attacks [#730](https://github.com/kemalcr/kemal/pull/730). Thanks @sdogruyol :pray:
+- Optimize JSON parameter parsing by directly using the request body IO. Thanks @sdogruyol :pray:
+
+# 1.8.0 (07-11-2025)
+
+- Enhance HEAD request handling by caching GET route lookups and optimize path construction using string interpolation for improved performance [#728](https://github.com/kemalcr/kemal/pull/728). Thanks @sdogruyol :pray:
+- Improve error messages [#726](https://github.com/kemalcr/kemal/pull/726). Thanks @sdogruyol :pray:
+- Optimize route and websocket lookups by caching results to reduce redundant processing in the HTTP server context [#725](https://github.com/kemalcr/kemal/pull/725). Thanks @sdogruyol :pray:
+- Replace full-flush Route cache with LRU and add a configurable max cache size [#724](https://github.com/kemalcr/kemal/pull/724). Thanks @sdogruyol :pray:
+
+# 1.7.3 (02-10-2025)
+
+- Refactor [#719](https://github.com/kemalcr/kemal/pull/719). Thanks @sdogruyol :pray:
+- Improve Kemal test suite. Thanks @sdogruyol :pray:
+
+# 1.7.2 (04-08-2025)
+
+- Move Kemal::Handler logic into separate module [#717](https://github.com/kemalcr/kemal/pull/717). Thanks @syeopite :pray:
+- Refactor server binding logic to avoid binding in test environment [#719](https://github.com/kemalcr/kemal/pull/719). Thanks @sdogruyol :pray:
+
+# 1.7.1 (14-04-2025)
+
+- Improve `StaticFileHandler` to align with latest Crystal implementation [#711](https://github.com/kemalcr/kemal/pull/711). Thanks @sdogruyol :pray:
+
+# 1.7.0 (14-04-2025)
+
+- ***(SECURITY)*** Fix a Path Traversal Security issue in `StaticFileHandler`. [See](https://packetstorm.news/files/id/190294/) for more details. Thanks a lot @ahmetumitbayram :pray:
+- Crystal 1.16.0 support :tada:
+- Add ability to add handlers for raised exceptions [#688](https://github.com/kemalcr/kemal/pull/688). Thanks @syeopite :pray:
+
+```crystal
+require "kemal"
+
+class NewException < Exception
+end
+
+get "/" do | env |
+  raise NewException.new()
+end
+
+error NewException do | env |
+  "An error occured!"
+end
+
+Kemal.run
+```
+
+- Add `all_files` method to `params` to support multiple file uploads in names ending with `[]` [#701](https://github.com/kemalcr/kemal/pull/701). Thanks @sdogruyol :pray:
+
+```crystal
+images = env.params.all_files["images[]"]?
+```
+
+- Embrace Crystal standard Log for logging [#705](https://github.com/kemalcr/kemal/pull/705). Thanks @hugopl :pray:
+- Cleanup temporary files for file uploads [#707](https://github.com/kemalcr/kemal/pull/707). Thanks @sdogruyol :pray:
+- Implement multiple partial ranges [#708](https://github.com/kemalcr/kemal/pull/708). Thanks @sdogruyol :pray:
+
 # 1.6.0 (12-10-2024)
 
 - Crystal 1.14.0 support :tada:

CONTRIBUTING.md

@@ -0,0 +1,59 @@
+# Contributing to Kemal
+
+Thank you for your interest in contributing to Kemal! We love pull requests from everyone.
+
+## Getting Started
+
+1. **Fork** the repository on GitHub.
+2. **Clone** your fork locally:
+   ```bash
+   git clone https://github.com/YOUR_USERNAME/kemal.git
+   cd kemal
+   ```
+3. **Install dependencies**:
+   ```bash
+   shards install
+   ```
+
+## Running Tests
+
+Before submitting a pull request, please ensure that all tests pass.
+
+```bash
+crystal spec
+```
+
+## Code Style
+
+Kemal follows the standard Crystal code style. Please ensure your code is formatted correctly before committing.
+
+```bash
+crystal tool format
+```
+
+## Submitting a Pull Request
+
+1. Create a new branch for your feature or bug fix:
+   ```bash
+   git checkout -b my-new-feature
+   ```
+2. Commit your changes with descriptive commit messages.
+3. Push your branch to your fork:
+   ```bash
+   git push origin my-new-feature
+   ```
+4. Open a **Pull Request** on the main Kemal repository.
+5. Describe your changes and link to any relevant issues.
+
+## Reporting Bugs
+
+If you find a bug, please open an issue on GitHub with:
+- A clear title and description.
+- Steps to reproduce the issue.
+- The version of Kemal and Crystal you are using.
+
+## Feature Requests
+
+We welcome new ideas! Please open an issue to discuss your feature request before implementing it.
+
+Thank you for contributing to Kemal! 🚀

README.md

@@ -2,45 +2,32 @@
 
 # Kemal
 
-Lightning Fast, Super Simple web framework.
+Kemal is the Fast, Effective, Simple Web Framework for Crystal. It's perfect for building Web Applications and APIs with minimal code.
 
 **THIS IS A FORK OF KEMAL. DIRECT TO FORK.MD FOR SPECIFICS ON THIS FORK.**
 
 [![CI](https://github.com/kemalcr/kemal/actions/workflows/ci.yml/badge.svg)](https://github.com/kemalcr/kemal/actions/workflows/ci.yml)
-[![Join the chat at https://gitter.im/sdogruyol/kemal](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/sdogruyol/kemal?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 
-# Super Simple ⚡️
+## Why Kemal?
 
-```ruby
-require "kemal"
+- 🚀 **Lightning Fast**: Built on Crystal, known for C-like performance
+- 💡 **Super Simple**: Minimal code needed to get started
+- 🛠 **Feature Rich**: Everything you need for modern web development
+- 🔧 **Flexible**: Easy to extend with middleware support
 
-# Matches GET "http://host:port/"
-get "/" do
-  "Hello World!"
-end
+## Quick Start
 
-# Creates a WebSocket handler.
-# Matches "ws://host:port/socket"
-ws "/socket" do |socket|
-  socket.send "Hello from Kemal!"
-end
+1. First, make sure you have [Crystal installed](https://crystal-lang.org/install/).
 
-Kemal.run
+2. Create a new Crystal application and step into it:
+
+```bash
+crystal init app my-kemal-app
+cd my-kemal-app
 ```
 
-Start your application!
-
-```
-crystal src/kemal_sample.cr
-```
-
-Go to _http://localhost:3000_
-
-Check [documentation](http://kemalcr.com) or [samples](https://github.com/kemalcr/kemal/tree/master/samples) for more.
-
-# Installation
-
-Add this to your application's `shard.yml`:
+3. Add Kemal to your app's `shard.yml`:
+>>>>>>> upstream/master
 
 ```yaml
 dependencies:
@@ -48,22 +35,78 @@ dependencies:
     github: kemalcr/kemal
 ```
 
-See also [Getting Started](http://kemalcr.com/guide/).
+4. Replace the contents of `src/my_kemal_app.cr` with your first Kemal app:
 
-# Features
+```crystal
+require "kemal"
 
-- Support all REST verbs
-- Websocket support
-- Request/Response context, easy parameter handling
-- Middleware support
-- Built-in JSON support
-- Built-in static file serving
-- Built-in view templating via [ECR](https://crystal-lang.org/api/ECR.html)
+# Basic route - responds to GET "http://localhost:3000/"
+get "/" do
+  "Hello World!"
+end
 
-# Documentation
+# JSON API example
+get "/api/status" do |env|
+  env.response.content_type = "application/json"
+  {"status": "ok"}.to_json
+end
 
-You can read the documentation at the official site [kemalcr.com](http://kemalcr.com)
+# WebSocket support
+ws "/chat" do |socket|
+  socket.send "Hello from Kemal WebSocket!"
+end
 
-## Thanks
+Kemal.run
+```
 
-Thanks to Manas for their awesome work on [Frank](https://github.com/manastech/frank).
+5. Install dependencies and run your application:
+
+```bash
+shards install
+crystal run src/my_kemal_app.cr
+```
+
+6. Visit [http://localhost:3000](http://localhost:3000) - That's it! 🎉
+
+## Key Features
+
+- 🚀 **High-performance by default**: Built on Crystal with a thin abstraction layer so you can serve a large number of requests with low latency and low memory footprint.
+- 🌐 **Full REST & HTTP support**: Handle all HTTP verbs (GET, POST, PUT, PATCH, DELETE, etc.) with a straightforward routing DSL.
+- 🔌 **WebSocket & real-time**: First-class WebSocket support for building chats, dashboards and other real-time experiences.
+- 📦 **JSON-first APIs**: Native JSON handling makes building JSON APIs and microservices feel natural.
+- 🗄️ **Static assets made easy**: Serve static files (assets, uploads, SPA bundles) efficiently from the same application.
+- 📝 **Template engine included**: Built-in ECR template engine for server‑rendered HTML when you need it.
+- 🔒 **Composable middleware**: Flexible middleware system to add logging, auth, rate limiting, metrics and more.
+- 🎯 **Ergonomic request/response API**: Simple access to params, headers, cookies and bodies via a clear context object.
+- 🍪 **Session management**: Easy session handling with [kemal-session](https://github.com/kemalcr/kemal-session), suitable for production apps.
+
+## Philosophy
+
+Kemal aims to be a simple, fast and reliable foundation for building production-grade web applications and APIs in Crystal.
+
+- **Simple core, powerful building blocks**: The core is intentionally simple and easy to reason about. Most power comes from Crystal itself and from middleware, not from hidden magic.
+- **Performance as a baseline, not a feature**: Crystal's native speed means high performance is the default. Kemal keeps abstractions thin so you stay close to the metal when you need to.
+- **Minimal assumptions, maximum flexibility**: Kemal does not force a specific ORM, template engine, or project layout. You are free to choose the tools that fit your application and your team.
+- **Batteries within reason**: Kemal ships with the essentials (routing, middleware, templates, static files, request/response helpers) while keeping advanced concerns in separate shards you can opt into as your app grows.
+
+Kemal is designed to feel familiar if you come from popular web frameworks, while embracing Crystal's strengths and keeping your application code straightforward, maintainable, and ready for production.
+
+## Learning Resources
+
+- 📚 [Official Documentation](http://kemalcr.com)
+- 💻 [Example Applications](https://github.com/kemalcr/kemal/tree/master/examples)
+- 🚀 [Kemal Guide](http://kemalcr.com/guide/)
+- 💬 [Community Chat](https://discord.gg/prSVAZJEpz)
+
+
+## Contributing
+
+We love contributions! Please read our [Contributing Guide](CONTRIBUTING.md) to get started.
+
+## Acknowledgments
+
+Special thanks to Manas for their work on [Frank](https://github.com/manastech/frank).
+
+## License
+
+Kemal is released under the MIT License.

examples/cookies/app.cr

@@ -0,0 +1,67 @@
+require "kemal"
+
+# This example demonstrates different ways to work with cookies in Kemal
+
+# Route to set various types of cookies
+get "/set-cookies" do |env|
+  # Basic cookie with just name and value
+  basic_cookie = HTTP::Cookie.new(
+    name: "BasicCookie",
+    value: "Hello from Kemal!"
+  )
+
+  # Secure cookie with additional security options
+  secure_cookie = HTTP::Cookie.new(
+    name: "SecureCookie",
+    value: "Sensitive Data",
+    http_only: true,                              # Cookie cannot be accessed via JavaScript
+    secure: true,                                 # Cookie only sent over HTTPS
+    path: "/",                                    # Cookie available for all paths
+    expires: Time.local + Time::Span.new(days: 7) # Cookie expires in 7 days
+  )
+
+  # Session cookie that expires when browser closes
+  session_cookie = HTTP::Cookie.new(
+    name: "SessionCookie",
+    value: "Temporary",
+    http_only: true
+  )
+
+  # Add all cookies to response
+  env.response.cookies << basic_cookie
+  env.response.cookies << secure_cookie
+  env.response.cookies << session_cookie
+
+  "Cookies have been set! Visit /show-cookies to view them."
+end
+
+# Route to display current cookies
+get "/show-cookies" do |env|
+  cookies = env.request.cookies
+  response = String.build do |str|
+    str << "<h1>Current Cookies:</h1>"
+    str << "<ul>"
+    cookies.each do |cookie|
+      str << "<li>#{cookie.name}: #{cookie.value}</li>"
+    end
+    str << "</ul>"
+  end
+  response
+end
+
+# Route to delete a specific cookie
+get "/delete-cookie/:name" do |env|
+  cookie_name = env.params.url["name"]
+
+  # Set cookie with immediate expiration to delete it
+  delete_cookie = HTTP::Cookie.new(
+    name: cookie_name,
+    value: "",
+    expires: Time.local - 1.day
+  )
+
+  env.response.cookies << delete_cookie
+  "Cookie '#{cookie_name}' has been deleted!"
+end
+
+Kemal.run

examples/cors/app.cr

@@ -0,0 +1,17 @@
+require "kemal"
+
+# Configure headers for static files using Kemal's static_headers helper
+static_headers do |response, filepath, filestat|
+  # For HTML files, add CORS header to allow requests from example.com
+  # This restricts access to HTML files to only that domain
+  if filepath =~ /\.html$/
+    response.headers.add("Access-Control-Allow-Origin", "example.com")
+  end
+
+  # Add Content-Size header for all static files
+  # This helps clients know the file size before downloading
+  response.headers.add("Content-Size", filestat.size.to_s)
+end
+
+# Start the Kemal web server
+Kemal.run

examples/file-download/app.cr

@@ -0,0 +1,18 @@
+require "kemal"
+
+# Define a route for the root path "/" that will handle file downloads
+get "/" do |env|
+  # Use Kemal's send_file helper to stream a file to the client
+  # Parameters:
+  # - env: The HTTP environment containing request/response data
+  # - "/path/to/your_file": The path to the file you want to download
+  #
+  # send_file will:
+  # - Set appropriate Content-Type header based on file extension
+  # - Stream the file in chunks to handle large files efficiently
+  # - Set Content-Disposition header for browser download behavior
+  send_file env, "/path/to/your_file"
+end
+
+# Start the Kemal web server
+Kemal.run

examples/file-upload/app.cr

@@ -0,0 +1,25 @@
+require "kemal"
+
+# Handle file uploads via POST request to /upload endpoint
+post "/upload" do |env|
+  # Get the uploaded file from the "image" field in the form
+  # The file is initially stored in a temporary location
+  uploaded_file = env.params.files["image"].tempfile
+
+  # Construct the destination path where we'll save the file
+  # - Kemal.config.public_folder is the configured public directory
+  # - "uploads/" is the subdirectory where we'll store uploads
+  # - File.basename gets just the filename from the temp file path
+  uploaded_file_path = ::File.join [Kemal.config.public_folder, "uploads/", File.basename(uploaded_file.path)]
+
+  # Open the destination file for writing and copy the uploaded file to it
+  File.open(uploaded_file_path, "w") do |file|
+    IO.copy(uploaded_file, file)
+  end
+
+  # Return a simple success message
+  "Upload ok"
+end
+
+# Start the Kemal server
+Kemal.run

examples/hello-world/app.cr

@@ -0,0 +1,7 @@
+require "kemal"
+
+get "/" do
+  "Hello Kemal!"
+end
+
+Kemal.run

examples/http-basic-auth/app.cr

@@ -0,0 +1,18 @@
+require "kemal"
+require "kemal-basic-auth"
+
+# Enable HTTP Basic Authentication
+# This will protect all routes with username/password authentication
+# - username: "username"
+# - password: "password"
+basic_auth "username", "password"
+
+# Define a route for the root path "/"
+get "/" do |_|
+  # This route will only execute if authentication is successful
+  # Otherwise, the browser will show a login prompt
+  "This is shown if basic auth successful."
+end
+
+# Start the Kemal web server
+Kemal.run

examples/http-basic-auth/custom-handler.cr

@@ -0,0 +1,23 @@
+require "kemal-basic-auth"
+
+# Create a custom authentication handler by inheriting from Kemal::BasicAuth::Handler
+class CustomAuthHandler < Kemal::BasicAuth::Handler
+  # Specify which routes should be protected by basic auth
+  # In this case, only /dashboard and /admin routes will require authentication
+  only ["/dashboard", "/admin"]
+
+  # Override the call method to implement custom authentication logic
+  def call(context)
+    # Skip authentication if the current route is not in the protected routes list
+    # This allows other routes to be accessed without authentication
+    return call_next(context) unless only_match?(context)
+
+    # Call the parent class's authentication logic for protected routes
+    # This will prompt for username/password and validate credentials
+    super
+  end
+end
+
+# Register our custom authentication handler with Kemal
+# This enables basic auth for the specified routes
+Kemal.config.auth_handler = CustomAuthHandler

examples/json-api/app.cr

@@ -0,0 +1,72 @@
+require "kemal"
+require "json"
+
+# Set JSON content type for all routes
+before_all do |env|
+  env.response.content_type = "application/json"
+end
+
+# In-memory storage for users
+USERS = [] of Hash(String, JSON::Any)
+
+# GET - List all users
+get "/users" do |_|
+  USERS.to_json
+end
+
+# GET - Get a specific user by index
+get "/users/:id" do |env|
+  id = env.params.url["id"].to_i
+
+  if id < USERS.size
+    USERS[id].to_json
+  else
+    env.response.status_code = 404
+    {error: "User not found"}.to_json
+  end
+end
+
+# POST - Create a new user
+post "/users" do |env|
+  # Parse request body as JSON
+  # ameba:disable Lint/NotNil
+  user = JSON.parse(env.request.body.not_nil!.gets_to_end)
+  # ameba:enable Lint/NotNil
+  USERS << user.as_h
+
+  env.response.status_code = 201
+  user.to_json
+end
+
+# PUT - Update a user
+put "/users/:id" do |env|
+  id = env.params.url["id"].to_i
+
+  if id < USERS.size
+    # Parse request body as JSON
+    # ameba:disable Lint/NotNil
+    updated_user = JSON.parse(env.request.body.not_nil!.gets_to_end)
+    # ameba:enable Lint/NotNil
+    USERS[id] = updated_user.as_h
+    updated_user.to_json
+  else
+    env.response.status_code = 404
+    {error: "User not found"}.to_json
+  end
+end
+
+# DELETE - Remove a user
+delete "/users/:id" do |env|
+  id = env.params.url["id"].to_i
+
+  if id < USERS.size
+    deleted_user = USERS.delete_at(id)
+    deleted_user.to_json
+  else
+    env.response.status_code = 404
+    {error: "User not found"}.to_json
+  end
+end
+
+# Start the Kemal web server
+Kemal.run

examples/json-mapping/app.cr

@@ -0,0 +1,32 @@
+require "kemal"
+require "json"
+
+# Define a User class that can be created from JSON data
+class User
+  # Include JSON::Serializable to add JSON parsing capabilities
+  # This allows converting JSON strings to User objects and vice versa
+  include JSON::Serializable
+
+  # Define properties that will be mapped from JSON
+  # These properties must match the keys in the incoming JSON
+  property username : String # User's username as a string
+  property password : String # User's password as a string
+end
+
+# Handle POST requests to the root path "/"
+post "/" do |env|
+  # Parse the request body as JSON and create a User object
+  # env.request.body contains the raw JSON data
+  # not_nil! ensures the body exists
+  # User.from_json converts the JSON string to a User object
+  # ameba:disable Lint/NotNil
+  user = User.from_json env.request.body.not_nil!
+  # ameba:enable Lint/NotNil
+
+  # Convert the user object back to JSON and return it
+  # This creates a JSON object with username and password fields
+  {username: user.username, password: user.password}.to_json
+end
+
+# Start the Kemal web server
+Kemal.run

examples/mysql-db/app.cr

@@ -0,0 +1,56 @@
+require "kemal"
+require "db"
+require "mysql"
+
+# Initialize a single DB connection
+DB_URL = "mysql://root:password@localhost:3306/mydb"
+DBC    = DB.open(DB_URL)
+
+# Example User model
+class User
+  include JSON::Serializable # To render json in HTTP::Response
+  include DB::Serializable   # To serialize from DB::ResultSet
+
+  property id : Int32
+  property name : String
+  property email : String
+
+  def initialize(@id, @name, @email)
+  end
+end
+
+# List all users
+get "/users" do |_|
+  # Serialize ResultSet
+  users = User.from_rs(DBC.query("SELECT * FROM users"))
+
+  # Return users array as JSON response
+  users.to_json
+end
+
+# Create a new user
+post "/users" do |env|
+  name = env.params.json["name"].as(String)
+  email = env.params.json["email"].as(String)
+
+  user = User.from_rs(DBC.query("INSERT INTO users (name, email) VALUES ($1, $2) RETURNING id, name, email", name, email)).first
+
+  {message: "User created with id: #{user.id}"}.to_json
+end
+
+# Delete a user
+delete "/users/:id" do |env|
+  id = env.params.url["id"].to_i
+
+  # Delete user and check if any rows were affected
+  result = DBC.exec "DELETE FROM users WHERE id = ?", id
+
+  if result.rows_affected > 0
+    {message: "User deleted successfully"}.to_json
+  else
+    env.response.status_code = 404
+    {message: "User not found"}.to_json
+  end
+end
+
+Kemal.run

examples/postgresql-db/app.cr

@@ -0,0 +1,56 @@
+require "kemal"
+require "db"
+require "pg"
+
+# Initialize a single DB connection
+DB_URL = "postgres://postgres:postgres@localhost:5432/mydb"
+DBC    = DB.open(DB_URL)
+
+# Example User model
+class User
+  include JSON::Serializable # To render json in HTTP::Response
+  include DB::Serializable   # To serialize from DB::ResultSet
+
+  property id : Int32
+  property name : String
+  property email : String
+
+  def initialize(@id, @name, @email)
+  end
+end
+
+# List all users
+get "/users" do |_|
+  # Serialize ResultSet
+  users = User.from_rs(DBC.query("SELECT * FROM users"))
+
+  # Return users array as JSON response
+  users.to_json
+end
+
+# Create a new user
+post "/users" do |env|
+  name = env.params.json["name"].as(String)
+  email = env.params.json["email"].as(String)
+
+  user = User.from_rs(DBC.query("INSERT INTO users (name, email) VALUES ($1, $2) RETURNING id, name, email", name, email)).first
+
+  {message: "User created with id: #{user.id}"}.to_json
+end
+
+# Delete a user
+delete "/users/:id" do |env|
+  id = env.params.url["id"].to_i
+
+  # Delete user and check if any rows were affected
+  result = DBC.exec "DELETE FROM users WHERE id = $1", id
+
+  if result.rows_affected > 0
+    {message: "User deleted successfully"}.to_json
+  else
+    env.response.status_code = 404
+    {message: "User not found"}.to_json
+  end
+end
+
+Kemal.run

examples/redis/app.cr

@@ -0,0 +1,58 @@
+require "kemal"
+require "redis"
+
+# Initialize Redis client
+REDIS = Redis.new(host: "localhost", port: 6379)
+
+# Store a value
+post "/store/:key" do |env|
+  key = env.params.url["key"]
+  value = env.params.json["value"].as(String)
+
+  REDIS.set(key, value)
+  {message: "Value stored successfully"}.to_json
+end
+
+# Retrieve a value
+get "/get/:key" do |env|
+  key = env.params.url["key"]
+
+  if value = REDIS.get(key)
+    {key: key, value: value}.to_json
+  else
+    env.response.status_code = 404
+    {message: "Key not found"}.to_json
+  end
+end
+
+# Delete a value
+delete "/:key" do |env|
+  key = env.params.url["key"]
+
+  if REDIS.del(key) > 0
+    {message: "Key deleted successfully"}.to_json
+  else
+    env.response.status_code = 404
+    {message: "Key not found"}.to_json
+  end
+end
+
+# Increment a counter
+post "/incr/:key" do |env|
+  key = env.params.url["key"]
+  new_value = REDIS.incr(key)
+
+  {key: key, value: new_value}.to_json
+end
+
+# Store with expiration
+post "/store_temp/:key" do |env|
+  key = env.params.url["key"]
+  value = env.params.json["value"].as(String)
+  ttl = env.params.json["ttl"].as(Int64)
+
+  REDIS.setex(key, ttl, value)
+  {message: "Value stored with expiration"}.to_json
+end
+
+Kemal.run

examples/reuse-port/app.cr

@@ -0,0 +1,19 @@
+require "kemal"
+
+# Define a simple route that returns a message
+get "/" do
+  "Reusing port 3000"
+end
+
+# Start Kemal with custom server configuration
+Kemal.run do |config|
+  # Get the server instance from the config
+  # ameba:disable Lint/NotNil
+  server = config.server.not_nil!
+  # ameba:enable Lint/NotNil
+
+  # Bind the server to port 3000 with reuse_port enabled
+  # reuse_port: true allows multiple processes to listen on the same port
+  # This is useful for load balancing across multiple worker processes
+  server.bind_tcp "0.0.0.0", 3000, reuse_port: true
+end

examples/unix-domain-socket/app.cr

@@ -0,0 +1,14 @@
+require "kemal"
+
+# Start Kemal with custom server configuration to use Unix Domain Socket
+Kemal.run do |config|
+  # Get the server instance from the config
+  # ameba:disable Lint/NotNil
+  server = config.server.not_nil!
+  # ameba:enable Lint/NotNil
+
+  # Bind the server to a Unix Domain Socket instead of TCP port
+  # Unix Domain Sockets provide faster inter-process communication on the same machine
+  # They are commonly used when the client and server are on the same host
+  server.bind_unix "path/to/socket.sock"
+end

examples/websocket-chat/app.cr

@@ -0,0 +1,33 @@
+require "kemal"
+
+# Array to store chat message history
+messages = [] of String
+# Array to keep track of connected WebSocket clients
+sockets = [] of HTTP::WebSocket
+
+# Create WebSocket endpoint at root path "/"
+ws "/" do |socket|
+  # Add newly connected client socket to our sockets array
+  sockets.push socket
+
+  # Handle incoming messages from clients
+  socket.on_message do |message|
+    # Store the new message in history
+    messages.push message
+    # Broadcast the updated message history to all connected clients
+    sockets.each do |a_socket|
+      a_socket.send messages.to_json
+    end
+  end
+
+  # Handle client disconnection
+  socket.on_close do |_|
+    # Remove disconnected client's socket from our array
+    sockets.delete(socket)
+    # Log disconnection event
+    puts "Closing Socket: #{socket}"
+  end
+end
+
+# Start the Kemal server
+Kemal.run

samples/hello_world.cr

@@ -1,8 +0,0 @@
-require "kemal"
-
-# Set root. If not specified the default content_type is 'text'
-get "/" do
-  "Hello Kemal!"
-end
-
-Kemal.run

samples/json_api.cr

@@ -1,11 +0,0 @@
-require "kemal"
-require "json"
-
-# You can easily access the context and set content_type like 'application/json'.
-# Look how easy to build a JSON serving API.
-get "/" do |env|
-  env.response.content_type = "application/json"
-  {name: "Serdar", age: 27}.to_json
-end
-
-Kemal.run

samples/websocket_server.cr

@@ -1,11 +0,0 @@
-require "kemal"
-
-ws "/" do |socket|
-  socket.send "Hello from Kemal!"
-
-  socket.on_message do |message|
-    socket.send "Echo back from server #{message}"
-  end
-end
-
-Kemal.run

shard.yml

@@ -1,5 +1,5 @@
 name: kemal
-version: 1.6.0
+version: 1.10.1
 
 authors:
   - Serdar Dogruyol <dogruyolserdar@gmail.com>
@@ -15,6 +15,7 @@ dependencies:
 development_dependencies:
   ameba:
     github: crystal-ameba/ameba
+    branch: master
 
 crystal: ">= 0.36.0"
 

spec/asset/hello_with_content_for.ecr

@@ -2,4 +2,4 @@ Hello <%= name %>
 
 <% content_for "meta" do %>
 <title>Kemal Spec</title>
-<% end %>
+<% end %>

spec/asset/layout_with_yield.ecr

@@ -5,4 +5,4 @@
 	<body>
 		<%= content %>
 	</body>
-</html>
+</html>

spec/asset/layout_with_yield_and_vars.ecr

@@ -7,4 +7,4 @@
     	<%= var1 %>
     	<%= var2 %>
 	</body>
-</html>
+</html>

spec/cli_spec.cr

@@ -0,0 +1,90 @@
+require "./spec_helper"
+
+{% if !flag?(:without_openssl) %}
+  private def run_cli_eval(cli_args : String)
+    output = IO::Memory.new
+    error = IO::Memory.new
+    status = Process.run(
+      "crystal",
+      [
+        "eval",
+        %(require "./src/kemal"; Kemal::CLI.new(#{cli_args})),
+      ],
+      output: output,
+      error: error,
+    )
+
+    {status, output.to_s, error.to_s}
+  end
+{% end %}
+
+describe "Kemal::CLI" do
+  it "parses host binding with long option" do
+    Kemal::CLI.new(["--bind", "127.0.0.1"])
+    Kemal.config.host_binding.should eq("127.0.0.1")
+  end
+
+  it "parses host binding with short option" do
+    Kemal::CLI.new(["-b", "192.168.1.10"])
+    Kemal.config.host_binding.should eq("192.168.1.10")
+  end
+
+  it "parses port with long and short options" do
+    Kemal::CLI.new(["--port", "4001"])
+    Kemal.config.port.should eq(4001)
+
+    Kemal::CLI.new(["-p", "5002"])
+    Kemal.config.port.should eq(5002)
+  end
+
+  it "raises for non-numeric port values" do
+    expect_raises(ArgumentError) do
+      Kemal::CLI.new(["--port", "abc"])
+    end
+  end
+
+  {% if !flag?(:without_openssl) %}
+    it "fails when ssl is enabled but key file is missing" do
+      status, _, stderr = run_cli_eval(%(["--ssl", "--ssl-cert-file", "cert.pem"]))
+
+      status.success?.should be_false
+      stderr.should contain("SSL configuration error: SSL key file not specified")
+    end
+
+    it "fails when ssl is enabled but certificate file is missing" do
+      status, _, stderr = run_cli_eval(%(["--ssl", "--ssl-key-file", "key.pem"]))
+
+      status.success?.should be_false
+      stderr.should contain("SSL configuration error: SSL certificate file not specified")
+    end
+
+    it "fails when short ssl flag is used without key file" do
+      status, _, stderr = run_cli_eval(%(["-s", "--ssl-cert-file", "cert.pem"]))
+
+      status.success?.should be_false
+      stderr.should contain("SSL configuration error: SSL key file not specified")
+    end
+
+    it "fails when key file argument is empty" do
+      status, _, stderr = run_cli_eval(%(["--ssl", "--ssl-key-file", "", "--ssl-cert-file", "cert.pem"]))
+
+      status.success?.should be_false
+      stderr.should contain("SSL configuration error: SSL key file not specified")
+    end
+
+    it "fails when cert file argument is empty" do
+      status, _, stderr = run_cli_eval(%(["--ssl", "--ssl-key-file", "key.pem", "--ssl-cert-file", ""]))
+
+      status.success?.should be_false
+      stderr.should contain("SSL configuration error: SSL certificate file not specified")
+    end
+
+    it "does not hit missing-file validation when both flags are present" do
+      status, _, stderr = run_cli_eval(%(["--ssl", "--ssl-key-file", "key.pem", "--ssl-cert-file", "cert.pem"]))
+
+      status.success?.should be_false
+      stderr.should_not contain("SSL configuration error: SSL key file not specified")
+      stderr.should_not contain("SSL configuration error: SSL certificate file not specified")
+    end
+  {% end %}
+end

spec/config_spec.cr

@@ -29,15 +29,19 @@ describe "Config" do
     config = Kemal.config
     config.add_handler CustomTestHandler.new
     Kemal.config.setup
-    config.handlers.size.should eq(8)
+    config.handlers.size.should eq(7)
   end
 
   it "toggles the shutdown message" do
     config = Kemal.config
     config.shutdown_message = false
-    config.shutdown_message.should eq false
+    config.shutdown_message.should be_false
     config.shutdown_message = true
-    config.shutdown_message.should eq true
+    config.shutdown_message.should be_true
+  end
+
+  it "sets default shutdown timeout to zero" do
+    Kemal::Config.new.shutdown_timeout.should eq 0.seconds
   end
 
   it "adds custom options" do

spec/context_spec.cr

@@ -104,4 +104,29 @@ describe "Context" do
       context.get?("another_non_existent_key").should be_nil
     end
   end
+
+  context "route cache invalidation" do
+    it "refreshes route lookup and url params after request method changes" do
+      put "/items/:id" { "ok" }
+
+      request = HTTP::Request.new(
+        "POST",
+        "/items/42",
+        body: "_method=PUT",
+        headers: HTTP::Headers{"Content-Type" => "application/x-www-form-urlencoded; charset=UTF-8"}
+      )
+
+      io = IO::Memory.new
+      response = HTTP::Server::Response.new(io)
+      context = HTTP::Server::Context.new(request, response)
+
+      context.params.url.empty?.should be_true
+
+      request.method = "PUT"
+      context.invalidate_route_cache
+
+      context.route_found?.should be_true
+      context.params.url["id"].should eq "42"
+    end
+  end
 end

spec/exception_handler_spec.cr

@@ -59,6 +59,99 @@ describe "Kemal::ExceptionHandler" do
     response.body.should eq "Something happened"
   end
 
+  it "renders custom error for a crystal exception" do
+    error RuntimeError do
+      "A RuntimeError has occurred"
+    end
+
+    get "/" do
+      raise RuntimeError.new
+    end
+
+    request = HTTP::Request.new("GET", "/")
+    io = IO::Memory.new
+    response = HTTP::Server::Response.new(io)
+    context = HTTP::Server::Context.new(request, response)
+    Kemal::ExceptionHandler::INSTANCE.next = Kemal::RouteHandler::INSTANCE
+    Kemal::ExceptionHandler::INSTANCE.call(context)
+    response.close
+    io.rewind
+    response = HTTP::Client::Response.from_io(io, decompress: false)
+    response.status_code.should eq 500
+    response.headers["Content-Type"].should eq "text/html"
+    response.body.should eq "A RuntimeError has occurred"
+  end
+
+  it "renders custom error for a custom exception" do
+    error CustomExceptionType do
+      "A custom exception of CustomExceptionType has occurred"
+    end
+
+    get "/" do
+      raise CustomExceptionType.new
+    end
+
+    request = HTTP::Request.new("GET", "/")
+    io = IO::Memory.new
+    response = HTTP::Server::Response.new(io)
+    context = HTTP::Server::Context.new(request, response)
+    Kemal::ExceptionHandler::INSTANCE.next = Kemal::RouteHandler::INSTANCE
+    Kemal::ExceptionHandler::INSTANCE.call(context)
+    response.close
+    io.rewind
+    response = HTTP::Client::Response.from_io(io, decompress: false)
+    response.status_code.should eq 500
+    response.headers["Content-Type"].should eq "text/html"
+    response.body.should eq "A custom exception of CustomExceptionType has occurred"
+  end
+
+  it "renders custom error for a custom exception with a specific HTTP status code" do
+    error CustomExceptionType do |env|
+      env.response.status_code = 503
+      "A custom exception of CustomExceptionType has occurred"
+    end
+
+    get "/" do
+      raise CustomExceptionType.new
+    end
+
+    request = HTTP::Request.new("GET", "/")
+    io = IO::Memory.new
+    response = HTTP::Server::Response.new(io)
+    context = HTTP::Server::Context.new(request, response)
+    Kemal::ExceptionHandler::INSTANCE.next = Kemal::RouteHandler::INSTANCE
+    Kemal::ExceptionHandler::INSTANCE.call(context)
+    response.close
+    io.rewind
+    response = HTTP::Client::Response.from_io(io, decompress: false)
+    response.status_code.should eq 503
+    response.headers["Content-Type"].should eq "text/html"
+    response.body.should eq "A custom exception of CustomExceptionType has occurred"
+  end
+
+  it "renders custom error for a child of a custom exception" do
+    error CustomExceptionType do |_, error|
+      "A custom exception of #{error.class} has occurred"
+    end
+
+    get "/" do
+      raise ChildCustomExceptionType.new
+    end
+
+    request = HTTP::Request.new("GET", "/")
+    io = IO::Memory.new
+    response = HTTP::Server::Response.new(io)
+    context = HTTP::Server::Context.new(request, response)
+    Kemal::ExceptionHandler::INSTANCE.next = Kemal::RouteHandler::INSTANCE
+    Kemal::ExceptionHandler::INSTANCE.call(context)
+    response.close
+    io.rewind
+    response = HTTP::Client::Response.from_io(io, decompress: false)
+    response.status_code.should eq 500
+    response.headers["Content-Type"].should eq "text/html"
+    response.body.should eq "A custom exception of ChildCustomExceptionType has occurred"
+  end
+
   it "overrides the content type for filters" do
     before_get do |env|
       env.response.content_type = "application/json"

spec/handler_spec.cr

@@ -77,7 +77,7 @@ describe "Handler" do
     filter_middleware._add_route_filter("GET", "/", :before) do |env|
       env.response << " so"
     end
-    add_handler CustomTestHandler.new
+    use CustomTestHandler.new
 
     get "/" do
       " Great"
@@ -92,7 +92,7 @@ describe "Handler" do
     get "/only" do
       "Get"
     end
-    add_handler OnlyHandler.new
+    use OnlyHandler.new
     request = HTTP::Request.new("GET", "/only")
     client_response = call_request_on_app(request)
     client_response.body.should eq "OnlyGet"
@@ -105,7 +105,7 @@ describe "Handler" do
     get "/exclude" do
       "Exclude"
     end
-    add_handler ExcludeHandler.new
+    use ExcludeHandler.new
     request = HTTP::Request.new("GET", "/")
     client_response = call_request_on_app(request)
     client_response.body.should eq "ExcludeGet"
@@ -118,7 +118,7 @@ describe "Handler" do
     get "/only" do
       "Get"
     end
-    add_handler PostOnlyHandler.new
+    use PostOnlyHandler.new
     request = HTTP::Request.new("POST", "/only")
     client_response = call_request_on_app(request)
     client_response.body.should eq "OnlyPost"
@@ -131,8 +131,8 @@ describe "Handler" do
     post "/only" do
       "Post"
     end
-    add_handler PostOnlyHandler.new
-    add_handler PostExcludeHandler.new
+    use PostOnlyHandler.new
+    use PostExcludeHandler.new
     request = HTTP::Request.new("POST", "/only")
     client_response = call_request_on_app(request)
     client_response.body.should eq "OnlyExcludePost"
@@ -140,7 +140,7 @@ describe "Handler" do
 
   it "adds a handler at given position" do
     post_handler = PostOnlyHandler.new
-    add_handler post_handler, 1
+    use post_handler, position: 1
     Kemal.config.setup
     Kemal.config.handlers[1].should eq post_handler
   end

spec/helpers_spec.cr

@@ -9,38 +9,23 @@ describe "Macros" do
     end
   end
 
-  describe "#add_handler" do
+  describe "#use" do
     it "adds a custom handler" do
-      add_handler CustomTestHandler.new
+      use CustomTestHandler.new
       Kemal.config.setup
-      Kemal.config.handlers.size.should eq 8
+      Kemal.config.handlers.size.should eq 7
     end
   end
 
   describe "#logging" do
     it "sets logging status" do
       logging false
-      Kemal.config.logging.should eq false
-    end
-
-    it "sets a custom logger" do
-      config = Kemal::Config::INSTANCE
-      logger CustomLogHandler.new
-      config.logger.should be_a(CustomLogHandler)
+      Kemal.config.logging.should be_false
     end
   end
 
   describe "#halt" do
     it "can break block with halt macro" do
-      get "/non-breaking" do
-        "hello"
-        "world"
-      end
-      request = HTTP::Request.new("GET", "/non-breaking")
-      client_response = call_request_on_app(request)
-      client_response.status_code.should eq(200)
-      client_response.body.should eq("world")
-
       get "/breaking" do |env|
         halt env, 404, "hello"
         "world"
@@ -61,6 +46,61 @@ describe "Macros" do
       client_response.status_code.should eq(200)
       client_response.body.should eq("")
     end
+
+    it "halts with chained status/json" do
+      get "/halt-status-json" do |env|
+        halt env.status(500).json({error: "Something went wrong"})
+        "should-not-render"
+      end
+
+      request = HTTP::Request.new("GET", "/halt-status-json")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(500)
+      client_response.headers["Content-Type"].should eq("application/json")
+      client_response.body.should eq(%({"error":"Something went wrong"}))
+    end
+
+    it "halts with chained json" do
+      get "/halt-json" do |env|
+        halt env.json({error: "Something went wrong"})
+        "should-not-render"
+      end
+
+      request = HTTP::Request.new("GET", "/halt-json")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(200)
+      client_response.headers["Content-Type"].should eq("application/json")
+      client_response.body.should eq(%({"error":"Something went wrong"}))
+    end
+
+    it "writes body when halting with chained json" do
+      get "/halt-json-raw" do |env|
+        halt env.status(500).json({error: "Something went wrong"})
+        "should-not-render"
+      end
+
+      request = HTTP::Request.new("GET", "/halt-json-raw")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(500)
+      client_response.headers["Content-Type"].should eq("application/json")
+      client_response.body.should eq(%({"error":"Something went wrong"}))
+    end
+
+    it "halts env" do
+      get "/halt-env" do |env|
+        env.response.status_code = 500
+        env.response.content_type = "application/json"
+        env.response.print({error: "Something went wrong"}.to_json)
+        halt env
+        "should-not-render"
+      end
+
+      request = HTTP::Request.new("GET", "/halt-env")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(500)
+      client_response.headers["Content-Type"].should eq("application/json")
+      client_response.body.should eq(%({"error":"Something went wrong"}))
+    end
   end
 
   describe "#callbacks" do
@@ -79,6 +119,23 @@ describe "Macros" do
       client_response.status_code.should eq(400)
       client_response.body.should eq("Missing origin.")
     end
+
+    it "writes body when halting with chained json in before filter" do
+      filter_middleware = Kemal::FilterHandler.new
+      filter_middleware._add_route_filter("GET", "/halt-json-filter", :before) do |env|
+        halt env.status(500).json({error: "Something went wrong"})
+      end
+
+      get "/halt-json-filter" do |_env|
+        "should-not-render"
+      end
+
+      request = HTTP::Request.new("GET", "/halt-json-filter")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(500)
+      client_response.headers["Content-Type"].should eq("application/json")
+      client_response.body.should eq(%({"error":"Something went wrong"}))
+    end
   end
 
   describe "#headers" do
@@ -145,29 +202,139 @@ describe "Macros" do
       response.status_code.should eq(200)
       response.headers["Content-Disposition"].should eq("attachment; filename=\"image.jpg\"")
     end
+
+    it "handles multiple range requests" do
+      get "/" do |env|
+        send_file env, "#{__DIR__}/asset/hello.ecr"
+      end
+
+      headers = HTTP::Headers{"Range" => "bytes=0-4,7-11"}
+      request = HTTP::Request.new("GET", "/", headers)
+      response = call_request_on_app(request)
+
+      response.status_code.should eq(206)
+      response.headers["Content-Type"].should match(/^multipart\/byteranges; boundary=kemal-/)
+      response.headers["Accept-Ranges"].should eq("bytes")
+
+      # Verify multipart response structure
+      body = response.body
+      boundary = response.headers["Content-Type"].split("boundary=")[1]
+      parts = body.split("--#{boundary}")
+      # Parts structure:
+      # 1. Empty part before first boundary
+      # 2. First content part (0-4)
+      # 3. Second content part (7-11)
+      # 4. Trailing part after last boundary
+      parts.size.should eq(4)
+
+      # First part (0-4)
+      first_part = parts[1]
+      first_part.should contain("Content-Type: multipart/byteranges")
+      first_part.should contain("Content-Range: bytes 0-4/18")
+      first_part.split("\r\n\r\n")[1].strip.should eq("Hello")
+
+      # Second part (7-11)
+      second_part = parts[2]
+      second_part.should contain("Content-Type: multipart/byteranges")
+      second_part.should contain("Content-Range: bytes 7-11/18")
+      second_part.split("\r\n\r\n")[1].strip.should eq("%= na")
+    end
+
+    it "handles invalid range requests" do
+      get "/" do |env|
+        send_file env, "#{__DIR__}/asset/hello.ecr"
+      end
+
+      # Invalid range format
+      headers = HTTP::Headers{"Range" => "invalid"}
+      request = HTTP::Request.new("GET", "/", headers)
+      response = call_request_on_app(request)
+      response.status_code.should eq(200)
+      response.body.should eq(File.read("#{__DIR__}/asset/hello.ecr"))
+
+      # Range out of bounds
+      headers = HTTP::Headers{"Range" => "bytes=100-200"}
+      request = HTTP::Request.new("GET", "/", headers)
+      response = call_request_on_app(request)
+      response.status_code.should eq(200)
+      response.body.should eq(File.read("#{__DIR__}/asset/hello.ecr"))
+
+      # Invalid range values
+      headers = HTTP::Headers{"Range" => "bytes=5-3"}
+      request = HTTP::Request.new("GET", "/", headers)
+      response = call_request_on_app(request)
+      response.status_code.should eq(200)
+      response.body.should eq(File.read("#{__DIR__}/asset/hello.ecr"))
+    end
+
+    it "handles empty range requests" do
+      get "/" do |env|
+        send_file env, "#{__DIR__}/asset/hello.ecr"
+      end
+
+      headers = HTTP::Headers{"Range" => "bytes="}
+      request = HTTP::Request.new("GET", "/", headers)
+      response = call_request_on_app(request)
+      response.status_code.should eq(200)
+      response.body.should eq(File.read("#{__DIR__}/asset/hello.ecr"))
+    end
+
+    it "handles overlapping ranges" do
+      get "/" do |env|
+        send_file env, "#{__DIR__}/asset/hello.ecr"
+      end
+
+      headers = HTTP::Headers{"Range" => "bytes=0-5,3-8"}
+      request = HTTP::Request.new("GET", "/", headers)
+      response = call_request_on_app(request)
+
+      response.status_code.should eq(206)
+      response.headers["Content-Type"].should match(/^multipart\/byteranges; boundary=kemal-/)
+
+      # Verify both ranges are included
+      body = response.body
+      boundary = response.headers["Content-Type"].split("boundary=")[1]
+      parts = body.split("--#{boundary}")
+      # Parts structure:
+      # 1. Empty part before first boundary
+      # 2. First content part (0-5)
+      # 3. Second content part (3-8)
+      # 4. Trailing part after last boundary
+      parts.size.should eq(4)
+
+      # First part (0-5)
+      first_part = parts[1]
+      first_part.should contain("Content-Range: bytes 0-5/18")
+      first_part.split("\r\n\r\n")[1].strip.should eq("Hello")
+
+      # Second part (3-8)
+      second_part = parts[2]
+      second_part.should contain("Content-Range: bytes 3-8/18")
+      second_part.split("\r\n\r\n")[1].strip.should eq("lo <%=")
+    end
   end
 
   describe "#gzip" do
     it "adds HTTP::CompressHandler to handlers" do
       gzip true
       Kemal.config.setup
-      Kemal.config.handlers[5].should be_a(HTTP::CompressHandler)
+      Kemal.config.handlers[4].should be_a(HTTP::CompressHandler)
     end
   end
 
   describe "#serve_static" do
     it "should disable static file hosting" do
       serve_static false
-      Kemal.config.serve_static.should eq false
+      Kemal.config.serve_static.should be_false
     end
 
-    it "should disble enable gzip and dir_listing" do
+    it "should enable gzip and dir_listing" do
       serve_static({"gzip" => true, "dir_listing" => true})
       conf = Kemal.config.serve_static
-      conf.is_a?(Hash).should eq true
+      conf.is_a?(Hash).should be_true
       if conf.is_a?(Hash)
-        conf["gzip"].should eq true
-        conf["dir_listing"].should eq true
+        conf["gzip"].should be_true
+        conf["dir_listing"].should be_true
       end
     end
   end

spec/log_handler_spec.cr

@@ -1,13 +1,6 @@
 require "./spec_helper"
 
 describe "Kemal::LogHandler" do
-  it "logs to the given IO" do
-    io = IO::Memory.new
-    logger = Kemal::LogHandler.new io
-    logger.write "Something"
-    io.to_s.should eq "Something"
-  end
-
   it "creates log message for each request" do
     request = HTTP::Request.new("GET", "/")
     io = IO::Memory.new

spec/middleware/filters_spec.cr

@@ -207,6 +207,22 @@ describe "Kemal::FilterHandler" do
     client_response = HTTP::Client::Response.from_io(io_with_context, decompress: false)
     client_response.body.should eq("true-true")
   end
+
+  it "executes before_all filter on 404" do
+    before_filter = FilterTest.new
+    before_filter.modified = "false"
+
+    filter_middleware = Kemal::FilterHandler.new
+    filter_middleware._add_route_filter("ALL", "*", :before) { before_filter.modified = "true" }
+
+    error 404 do
+      before_filter.modified
+    end
+
+    request = HTTP::Request.new("GET", "/not_found")
+    client_response = call_request_on_app(request)
+    client_response.body.should eq("true")
+  end
 end
 
 class FilterTest

spec/override_method_handler_spec.cr

@@ -26,4 +26,48 @@ describe "Kemal::OverrideMethodHandler" do
 
     context.request.method.should eq "PATCH"
   end
+
+  it "routes POST with _method=PUT to PUT handler in real app" do
+    use Kemal::OverrideMethodHandler::INSTANCE
+
+    put "/items/:id" do |env|
+      "updated #{env.params.url["id"]}"
+    end
+
+    request = HTTP::Request.new(
+      "POST",
+      "/items/42",
+      body: "_method=PUT",
+      headers: HTTP::Headers{"Content-Type" => "application/x-www-form-urlencoded; charset=UTF-8"}
+    )
+
+    response = call_request_on_app(request)
+
+    response.status_code.should eq 200
+    response.body.should eq "updated 42"
+  end
+
+  it "does not override method when _method is not allowed" do
+    use Kemal::OverrideMethodHandler::INSTANCE
+
+    post "/items/:id" do |env|
+      "posted #{env.params.url["id"]}"
+    end
+
+    put "/items/:id" do |env|
+      "updated #{env.params.url["id"]}"
+    end
+
+    request = HTTP::Request.new(
+      "POST",
+      "/items/42",
+      body: "_method=TRACE",
+      headers: HTTP::Headers{"Content-Type" => "application/x-www-form-urlencoded; charset=UTF-8"}
+    )
+
+    response = call_request_on_app(request)
+
+    response.status_code.should eq 200
+    response.body.should eq "posted 42"
+  end
 end

spec/param_parser_spec.cr

@@ -174,7 +174,7 @@ describe "ParamParser" do
       body_params.to_s.should eq("")
 
       json_params = Kemal::ParamParser.new(request).json
-      json_params.should eq({} of String => Nil | String | Int64 | Float64 | Bool | Hash(String, JSON::Any) | Array(JSON::Any))
+      json_params.should eq({} of String => String | Int64 | Float64 | Bool | Hash(String, JSON::Any) | Array(JSON::Any)?)
     end
   end
 
@@ -201,4 +201,127 @@ describe "ParamParser" do
       body_params.to_s.should eq("")
     end
   end
+
+  describe "raw_body" do
+    it "returns raw body for url-encoded form" do
+      request = HTTP::Request.new(
+        "POST",
+        "/",
+        body: "name=serdar&age=99",
+        headers: HTTP::Headers{"Content-Type" => "application/x-www-form-urlencoded"},
+      )
+
+      parser = Kemal::ParamParser.new(request)
+      parser.raw_body.should eq("name=serdar&age=99")
+      parser.body["name"].should eq("serdar")
+      parser.body["age"].should eq("99")
+    end
+
+    it "returns raw body for JSON" do
+      request = HTTP::Request.new(
+        "POST",
+        "/",
+        body: "{\"name\": \"Serdar\"}",
+        headers: HTTP::Headers{"Content-Type" => "application/json"},
+      )
+
+      parser = Kemal::ParamParser.new(request)
+      parser.raw_body.should eq("{\"name\": \"Serdar\"}")
+      parser.json["name"].should eq("Serdar")
+    end
+
+    it "caches body so it can be accessed multiple times" do
+      request = HTTP::Request.new(
+        "POST",
+        "/",
+        body: "foo=bar&baz=qux",
+        headers: HTTP::Headers{"Content-Type" => "application/x-www-form-urlencoded"},
+      )
+
+      parser = Kemal::ParamParser.new(request)
+      parser.raw_body.should eq("foo=bar&baz=qux")
+      parser.raw_body.should eq("foo=bar&baz=qux")
+      parser.body["foo"].should eq("bar")
+      parser.raw_body.should eq("foo=bar&baz=qux")
+    end
+
+    it "returns empty string for unsupported content types" do
+      request = HTTP::Request.new(
+        "POST",
+        "/",
+        body: "some body",
+        headers: HTTP::Headers{"Content-Type" => "text/plain"},
+      )
+
+      parser = Kemal::ParamParser.new(request)
+      parser.raw_body.should eq("")
+    end
+
+    it "returns empty string when content-type is missing" do
+      request = HTTP::Request.new("POST", "/", body: "some body")
+
+      parser = Kemal::ParamParser.new(request)
+      parser.raw_body.should eq("")
+    end
+  end
+
+  context "Payload too large" do
+    it "raises PayloadTooLarge when body exceeds limit" do
+      Kemal.config.max_request_body_size = 10
+      request = HTTP::Request.new(
+        "POST",
+        "/",
+        body: "12345678901",
+        headers: HTTP::Headers{"Content-Type" => "application/x-www-form-urlencoded"},
+      )
+
+      expect_raises(Kemal::Exceptions::PayloadTooLarge) do
+        Kemal::ParamParser.new(request).body
+      end
+    end
+
+    it "raises PayloadTooLarge when Content-Length exceeds limit" do
+      Kemal.config.max_request_body_size = 10
+      request = HTTP::Request.new(
+        "POST",
+        "/",
+        body: "1",
+        headers: HTTP::Headers{
+          "Content-Type" => "application/x-www-form-urlencoded",
+        },
+      )
+      request.headers["Content-Length"] = "11"
+
+      expect_raises(Kemal::Exceptions::PayloadTooLarge) do
+        Kemal::ParamParser.new(request).body
+      end
+    end
+
+    it "parses body when size is within limit" do
+      Kemal.config.max_request_body_size = 20
+      request = HTTP::Request.new(
+        "POST",
+        "/",
+        body: "name=serdar",
+        headers: HTTP::Headers{"Content-Type" => "application/x-www-form-urlencoded"},
+      )
+
+      body_params = Kemal::ParamParser.new(request).body
+      body_params["name"].should eq("serdar")
+    end
+
+    it "raises PayloadTooLarge for JSON body exceeding limit" do
+      Kemal.config.max_request_body_size = 10
+      request = HTTP::Request.new(
+        "POST",
+        "/",
+        body: "{\"foo\":\"bar\"}",
+        headers: HTTP::Headers{"Content-Type" => "application/json"},
+      )
+
+      expect_raises(Kemal::Exceptions::PayloadTooLarge) do
+        Kemal::ParamParser.new(request).json
+      end
+    end
+  end
 end

spec/path_handler_spec.cr

@@ -0,0 +1,265 @@
+require "./spec_helper"
+
+# Test middleware that sets a header
+class TestHeaderHandler < Kemal::Handler
+  def initialize(@header_name : String, @header_value : String)
+  end
+
+  def call(env)
+    env.response.headers[@header_name] = @header_value
+    call_next(env)
+  end
+end
+
+# Test middleware that blocks requests
+class BlockingHandler < Kemal::Handler
+  def call(env)
+    env.response.status_code = 401
+    env.response.print "Blocked"
+    # Don't call_next - stop the chain
+  end
+end
+
+# Test middleware that sets context value
+class ContextSetterHandler < Kemal::Handler
+  def initialize(@key : String, @value : String)
+  end
+
+  def call(env)
+    env.set @key, @value
+    call_next(env)
+  end
+end
+
+describe "PathHandler" do
+  describe "use (global)" do
+    it "adds middleware that runs for all requests" do
+      use TestHeaderHandler.new("X-Global", "yes")
+
+      get "/test1" do
+        "test1"
+      end
+
+      get "/other/path" do
+        "other"
+      end
+
+      request1 = HTTP::Request.new("GET", "/test1")
+      response1 = call_request_on_app(request1)
+      response1.headers["X-Global"].should eq("yes")
+
+      request2 = HTTP::Request.new("GET", "/other/path")
+      response2 = call_request_on_app(request2)
+      response2.headers["X-Global"].should eq("yes")
+    end
+  end
+
+  describe "use with path prefix" do
+    it "runs middleware only for matching path prefix" do
+      use "/api", TestHeaderHandler.new("X-API", "true")
+
+      get "/api/users" do
+        "api users"
+      end
+
+      get "/web/home" do
+        "web home"
+      end
+
+      # Should have header for /api/*
+      api_request = HTTP::Request.new("GET", "/api/users")
+      api_response = call_request_on_app(api_request)
+      api_response.headers["X-API"]?.should eq("true")
+      api_response.body.should eq("api users")
+
+      # Should NOT have header for /web/*
+      web_request = HTTP::Request.new("GET", "/web/home")
+      web_response = call_request_on_app(web_request)
+      web_response.headers["X-API"]?.should be_nil
+      web_response.body.should eq("web home")
+    end
+
+    it "matches exact path" do
+      use "/api", TestHeaderHandler.new("X-Exact", "matched")
+
+      get "/api" do
+        "api root"
+      end
+
+      request = HTTP::Request.new("GET", "/api")
+      response = call_request_on_app(request)
+      response.headers["X-Exact"]?.should eq("matched")
+    end
+
+    it "matches nested paths" do
+      use "/api", TestHeaderHandler.new("X-Nested", "yes")
+
+      get "/api/v1/users/123/posts" do
+        "nested"
+      end
+
+      request = HTTP::Request.new("GET", "/api/v1/users/123/posts")
+      response = call_request_on_app(request)
+      response.headers["X-Nested"]?.should eq("yes")
+    end
+
+    it "does not match similar prefixes" do
+      use "/api", TestHeaderHandler.new("X-API-Only", "true")
+
+      get "/apiv2/users" do
+        "apiv2"
+      end
+
+      get "/api-old/users" do
+        "api-old"
+      end
+
+      # /apiv2 should NOT match /api
+      request1 = HTTP::Request.new("GET", "/apiv2/users")
+      response1 = call_request_on_app(request1)
+      response1.headers["X-API-Only"]?.should be_nil
+
+      # /api-old should NOT match /api
+      request2 = HTTP::Request.new("GET", "/api-old/users")
+      response2 = call_request_on_app(request2)
+      response2.headers["X-API-Only"]?.should be_nil
+    end
+
+    it "does not match root when prefix is set" do
+      use "/admin", TestHeaderHandler.new("X-Admin", "true")
+
+      get "/" do
+        "home"
+      end
+
+      request = HTTP::Request.new("GET", "/")
+      response = call_request_on_app(request)
+      response.headers["X-Admin"]?.should be_nil
+    end
+  end
+
+  describe "multiple middlewares" do
+    it "runs multiple middlewares in order" do
+      use "/api", TestHeaderHandler.new("X-First", "1")
+      use "/api", TestHeaderHandler.new("X-Second", "2")
+
+      get "/api/test" do
+        "test"
+      end
+
+      request = HTTP::Request.new("GET", "/api/test")
+      response = call_request_on_app(request)
+      response.headers["X-First"]?.should eq("1")
+      response.headers["X-Second"]?.should eq("2")
+    end
+
+    it "supports array of middlewares" do
+      use "/multi", [
+        TestHeaderHandler.new("X-A", "a"),
+        TestHeaderHandler.new("X-B", "b"),
+        TestHeaderHandler.new("X-C", "c"),
+      ]
+
+      get "/multi/test" do
+        "multi"
+      end
+
+      request = HTTP::Request.new("GET", "/multi/test")
+      response = call_request_on_app(request)
+      response.headers["X-A"]?.should eq("a")
+      response.headers["X-B"]?.should eq("b")
+      response.headers["X-C"]?.should eq("c")
+    end
+
+    it "different paths have different middlewares" do
+      use "/api", TestHeaderHandler.new("X-API", "api")
+      use "/admin", TestHeaderHandler.new("X-Admin", "admin")
+
+      get "/api/data" do
+        "api data"
+      end
+
+      get "/admin/dashboard" do
+        "admin dashboard"
+      end
+
+      api_request = HTTP::Request.new("GET", "/api/data")
+      api_response = call_request_on_app(api_request)
+      api_response.headers["X-API"]?.should eq("api")
+      api_response.headers["X-Admin"]?.should be_nil
+
+      admin_request = HTTP::Request.new("GET", "/admin/dashboard")
+      admin_response = call_request_on_app(admin_request)
+      admin_response.headers["X-Admin"]?.should eq("admin")
+      admin_response.headers["X-API"]?.should be_nil
+    end
+  end
+
+  describe "middleware can block requests" do
+    it "middleware can stop the chain" do
+      use "/protected", BlockingHandler.new
+
+      get "/protected/secret" do
+        "secret data"
+      end
+
+      get "/public" do
+        "public data"
+      end
+
+      # Protected route should be blocked
+      protected_request = HTTP::Request.new("GET", "/protected/secret")
+      protected_response = call_request_on_app(protected_request)
+      protected_response.status_code.should eq(401)
+      protected_response.body.should eq("Blocked")
+
+      # Public route should work
+      public_request = HTTP::Request.new("GET", "/public")
+      public_response = call_request_on_app(public_request)
+      public_response.status_code.should eq(200)
+      public_response.body.should eq("public data")
+    end
+  end
+
+  describe "middleware with context" do
+    it "middleware can set context values" do
+      use "/ctx", ContextSetterHandler.new("middleware_ran", "yes")
+
+      get "/ctx/check" do |env|
+        env.get("middleware_ran").to_s
+      end
+
+      request = HTTP::Request.new("GET", "/ctx/check")
+      response = call_request_on_app(request)
+      response.body.should eq("yes")
+    end
+  end
+
+  describe "PathHandler" do
+    describe "#matches_prefix?" do
+      it "root prefix matches all" do
+        get "/anything" do
+          "ok"
+        end
+
+        use "/", TestHeaderHandler.new("X-Root", "all")
+
+        request = HTTP::Request.new("GET", "/anything")
+        response = call_request_on_app(request)
+        response.headers["X-Root"]?.should eq("all")
+      end
+
+      it "empty prefix matches all" do
+        use "", TestHeaderHandler.new("X-Empty", "all")
+
+        get "/some/path" do
+          "ok"
+        end
+
+        request = HTTP::Request.new("GET", "/some/path")
+        response = call_request_on_app(request)
+        response.headers["X-Empty"]?.should eq("all")
+      end
+    end
+  end
+end

spec/request_log_handler_spec.cr

@@ -0,0 +1,17 @@
+require "log/spec"
+require "./spec_helper"
+
+describe Kemal::RequestLogHandler do
+  it "creates log message for each request" do
+    Log.setup(:none)
+
+    request = HTTP::Request.new("GET", "/")
+    response = HTTP::Server::Response.new(IO::Memory.new)
+    context = HTTP::Server::Context.new(request, response)
+    logger = Kemal::RequestLogHandler.new
+    Log.capture do |logs|
+      logger.call(context)
+      logs.check(:info, /404 GET \/ \d+.*s/)
+    end
+  end
+end

spec/response_helpers_spec.cr

@@ -0,0 +1,245 @@
+require "./spec_helper"
+
+describe "Response Helpers" do
+  describe "#json" do
+    it "sets content-type to application/json" do
+      get "/json-test" do |env|
+        env.json({message: "hello"})
+      end
+
+      request = HTTP::Request.new("GET", "/json-test")
+      client_response = call_request_on_app(request)
+      client_response.headers["Content-Type"].should eq("application/json")
+    end
+
+    it "serializes hash to JSON" do
+      get "/json-hash" do |env|
+        env.json({name: "alice", age: 30})
+      end
+
+      request = HTTP::Request.new("GET", "/json-hash")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq(%({"name":"alice","age":30}))
+    end
+
+    it "serializes array to JSON" do
+      get "/json-array" do |env|
+        env.json([1, 2, 3])
+      end
+
+      request = HTTP::Request.new("GET", "/json-array")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("[1,2,3]")
+    end
+
+    it "accepts custom content_type (e.g. JSON API)" do
+      get "/json-api" do |env|
+        env.json({data: [] of String}, content_type: "application/vnd.api+json")
+      end
+
+      request = HTTP::Request.new("GET", "/json-api")
+      client_response = call_request_on_app(request)
+      client_response.headers["Content-Type"].should eq("application/vnd.api+json")
+      client_response.body.should eq(%({"data":[]}))
+    end
+  end
+
+  describe "#html" do
+    it "sets content-type to text/html" do
+      get "/html-test" do |env|
+        env.html("<h1>Hello</h1>")
+      end
+
+      request = HTTP::Request.new("GET", "/html-test")
+      client_response = call_request_on_app(request)
+      client_response.headers["Content-Type"].should eq("text/html; charset=utf-8")
+    end
+
+    it "returns HTML content" do
+      get "/html-content" do |env|
+        env.html("<div>Content</div>")
+      end
+
+      request = HTTP::Request.new("GET", "/html-content")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("<div>Content</div>")
+    end
+  end
+
+  describe "#text" do
+    it "sets content-type to text/plain" do
+      get "/text-test" do |env|
+        env.text("Hello World")
+      end
+
+      request = HTTP::Request.new("GET", "/text-test")
+      client_response = call_request_on_app(request)
+      client_response.headers["Content-Type"].should eq("text/plain; charset=utf-8")
+    end
+
+    it "returns plain text content" do
+      get "/text-content" do |env|
+        env.text("Plain text here")
+      end
+
+      request = HTTP::Request.new("GET", "/text-content")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("Plain text here")
+    end
+  end
+
+  describe "#xml" do
+    it "sets content-type to application/xml" do
+      get "/xml-test" do |env|
+        env.xml("<root></root>")
+      end
+
+      request = HTTP::Request.new("GET", "/xml-test")
+      client_response = call_request_on_app(request)
+      client_response.headers["Content-Type"].should eq("application/xml; charset=utf-8")
+    end
+
+    it "returns XML content" do
+      get "/xml-content" do |env|
+        env.xml(%(<?xml version="1.0"?><rss><channel></channel></rss>))
+      end
+
+      request = HTTP::Request.new("GET", "/xml-content")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq(%(<?xml version="1.0"?><rss><channel></channel></rss>))
+    end
+  end
+
+  describe "#status" do
+    it "sets the response status code" do
+      get "/status-only" do |env|
+        env.status(204)
+        ""
+      end
+
+      request = HTTP::Request.new("GET", "/status-only")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(204)
+    end
+
+    it "is chainable with json" do
+      get "/status-json" do |env|
+        env.status(201).json({id: 1, created: true})
+      end
+
+      request = HTTP::Request.new("GET", "/status-json")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(201)
+      client_response.headers["Content-Type"].should eq("application/json")
+      client_response.body.should eq(%({"id":1,"created":true}))
+    end
+
+    it "is chainable with html" do
+      get "/status-html" do |env|
+        env.status(404).html("<h1>Not Found</h1>")
+      end
+
+      request = HTTP::Request.new("GET", "/status-html")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(404)
+      client_response.headers["Content-Type"].should eq("text/html; charset=utf-8")
+    end
+
+    it "is chainable with text" do
+      get "/status-text" do |env|
+        env.status(500).text("Internal Server Error")
+      end
+
+      request = HTTP::Request.new("GET", "/status-text")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(500)
+      client_response.headers["Content-Type"].should eq("text/plain; charset=utf-8")
+    end
+
+    it "is chainable with xml" do
+      get "/status-xml" do |env|
+        env.status(400).xml("<error>Bad Request</error>")
+      end
+
+      request = HTTP::Request.new("GET", "/status-xml")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(400)
+      client_response.headers["Content-Type"].should eq("application/xml; charset=utf-8")
+    end
+
+    it "accepts HTTP::Status and is chainable with json" do
+      get "/status-enum-json" do |env|
+        env.status(:not_found).json({error: "User not found"})
+      end
+
+      request = HTTP::Request.new("GET", "/status-enum-json")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(404)
+      client_response.headers["Content-Type"].should eq("application/json")
+      client_response.body.should contain("User not found")
+    end
+  end
+
+  describe "real-world scenarios" do
+    it "handles REST API create endpoint" do
+      post "/api/users" do |env|
+        env.status(201).json({id: 42, name: "Alice", created_at: "2024-01-01"})
+      end
+
+      request = HTTP::Request.new("POST", "/api/users")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(201)
+      client_response.headers["Content-Type"].should eq("application/json")
+    end
+
+    it "handles REST API not found" do
+      get "/api/users/999" do |env|
+        env.status(404).json({error: "User not found", code: "USER_NOT_FOUND"})
+      end
+
+      request = HTTP::Request.new("GET", "/api/users/999")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(404)
+      client_response.body.should contain("User not found")
+    end
+
+    it "handles validation error" do
+      post "/api/validate" do |env|
+        env.status(422).json({
+          error:  "Validation failed",
+          fields: {
+            email: "is invalid",
+            name:  "is required",
+          },
+        })
+      end
+
+      request = HTTP::Request.new("POST", "/api/validate")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(422)
+      client_response.body.should contain("Validation failed")
+    end
+
+    it "handles health check endpoint" do
+      get "/health" do |env|
+        env.text("OK")
+      end
+
+      request = HTTP::Request.new("GET", "/health")
+      client_response = call_request_on_app(request)
+      client_response.status_code.should eq(200)
+      client_response.body.should eq("OK")
+    end
+
+    it "handles RSS feed" do
+      get "/feed.xml" do |env|
+        env.xml(%(<?xml version="1.0" encoding="UTF-8"?><rss version="2.0"><channel><title>Blog</title></channel></rss>))
+      end
+
+      request = HTTP::Request.new("GET", "/feed.xml")
+      client_response = call_request_on_app(request)
+      client_response.headers["Content-Type"].should eq("application/xml; charset=utf-8")
+      client_response.body.should contain("<rss")
+    end
+  end
+end

spec/route_handler_spec.cr

@@ -130,7 +130,7 @@ describe "Kemal::RouteHandler" do
     client_response = call_request_on_app(request)
     client_response.status_code.should eq(302)
     client_response.body.should eq("")
-    client_response.headers.has_key?("Location").should eq(true)
+    client_response.headers.has_key?("Location").should be_true
   end
 
   it "redirects with body" do
@@ -141,7 +141,7 @@ describe "Kemal::RouteHandler" do
     client_response = call_request_on_app(request)
     client_response.status_code.should eq(302)
     client_response.body.should eq("Redirecting to /login")
-    client_response.headers.has_key?("Location").should eq(true)
+    client_response.headers.has_key?("Location").should be_true
   end
 
   it "redirects and closes response in before filter" do
@@ -159,7 +159,7 @@ describe "Kemal::RouteHandler" do
     client_response = call_request_on_app(request)
     client_response.status_code.should eq(302)
     client_response.body.should eq("")
-    client_response.headers.has_key?("Location").should eq(true)
+    client_response.headers.has_key?("Location").should be_true
   end
 
   it "redirects in before filter without closing response" do
@@ -177,6 +177,136 @@ describe "Kemal::RouteHandler" do
     client_response = call_request_on_app(request)
     client_response.status_code.should eq(302)
     client_response.body.should eq("home page")
-    client_response.headers.has_key?("Location").should eq(true)
+    client_response.headers.has_key?("Location").should be_true
+  end
+
+  context "LRU cache" do
+    it "evicts least recently used entries instead of clearing entirely" do
+      # Use a small capacity to make the test fast and deterministic
+      small_capacity = 8
+      # Replace the cache instance with a smaller-capacity LRU for this test
+      Kemal::RouteHandler::INSTANCE.cached_routes = Kemal::LRUCache(String, Radix::Result(Kemal::Route)).new(small_capacity)
+
+      # Define more routes than capacity
+      0.upto(15) do |i|
+        get "/lru_eviction_#{i}" do
+          "ok"
+        end
+      end
+
+      # Access the first `small_capacity` routes to fill the cache
+      0.upto(small_capacity - 1) do |i|
+        Kemal::RouteHandler::INSTANCE.lookup_route("GET", "/lru_eviction_#{i}")
+      end
+
+      Kemal::RouteHandler::INSTANCE.cached_routes.size.should eq small_capacity
+
+      # Access some new routes to trigger eviction
+      small_capacity.upto(small_capacity + 3) do |i|
+        Kemal::RouteHandler::INSTANCE.lookup_route("GET", "/lru_eviction_#{i}")
+      end
+
+      # Cache should still be capped at capacity
+      Kemal::RouteHandler::INSTANCE.cached_routes.size.should eq small_capacity
+    end
+
+    it "retains recently used keys and evicts the least recently used" do
+      small_capacity = 4
+      Kemal::RouteHandler::INSTANCE.cached_routes = Kemal::LRUCache(String, Radix::Result(Kemal::Route)).new(small_capacity)
+
+      0.upto(5) do |i|
+        get "/lru_recency_#{i}" do
+          "ok"
+        end
+      end
+
+      # Fill cache with 0..3
+      0.upto(3) do |i|
+        Kemal::RouteHandler::INSTANCE.lookup_route("GET", "/lru_recency_#{i}")
+      end
+
+      # Touch 0 and 1 to make them most recent
+      [0, 1].each do |i|
+        Kemal::RouteHandler::INSTANCE.lookup_route("GET", "/lru_recency_#{i}")
+      end
+
+      # Insert 4 -> should evict least recent among {2,3}
+      Kemal::RouteHandler::INSTANCE.lookup_route("GET", "/lru_recency_4")
+
+      # Insert 5 -> should evict the other of {2,3}
+      Kemal::RouteHandler::INSTANCE.lookup_route("GET", "/lru_recency_5")
+
+      # Now 0 and 1 must still resolve from cache, and size is capped
+      Kemal::RouteHandler::INSTANCE.cached_routes.size.should eq small_capacity
+
+      # A fresh lookup for 0 and 1 should be cache hits and not raise
+      Kemal::RouteHandler::INSTANCE.lookup_route("GET", "/lru_recency_0").found?.should be_true
+      Kemal::RouteHandler::INSTANCE.lookup_route("GET", "/lru_recency_1").found?.should be_true
+    end
+
+    it "caches HEAD fallback GET lookups without growing beyond 1 for same path" do
+      cap = 16
+      Kemal::RouteHandler::INSTANCE.cached_routes = Kemal::LRUCache(String, Radix::Result(Kemal::Route)).new(cap)
+
+      get "/head_fallback" do
+        "ok"
+      end
+
+      # First HEAD should fallback to GET and cache one entry keyed by HEAD+path
+      Kemal::RouteHandler::INSTANCE.lookup_route("HEAD", "/head_fallback").found?.should be_true
+      Kemal::RouteHandler::INSTANCE.cached_routes.size.should eq 1
+
+      # Second HEAD lookup should be a cache hit; size must remain 1
+      Kemal::RouteHandler::INSTANCE.lookup_route("HEAD", "/head_fallback").found?.should be_true
+      Kemal::RouteHandler::INSTANCE.cached_routes.size.should eq 1
+    end
+
+    it "keeps size capped under heavy churn with large capacity" do
+      large_capacity = 4096
+      Kemal::RouteHandler::INSTANCE.cached_routes = Kemal::LRUCache(String, Radix::Result(Kemal::Route)).new(large_capacity)
+
+      0.upto(12000) do |i|
+        get "/lru_heavy_#{i}" do
+          "ok"
+        end
+      end
+
+      # Fill and churn beyond capacity
+      0.upto(11999) do |i|
+        Kemal::RouteHandler::INSTANCE.lookup_route("GET", "/lru_heavy_#{i}")
+      end
+
+      Kemal::RouteHandler::INSTANCE.cached_routes.size.should eq large_capacity
+
+      # Additional churn should not increase size
+      12000.upto(14000) do |i|
+        get "/lru_heavy_more_#{i}" do
+          "ok"
+        end
+        Kemal::RouteHandler::INSTANCE.lookup_route("GET", "/lru_heavy_more_#{i}")
+      end
+
+      Kemal::RouteHandler::INSTANCE.cached_routes.size.should eq large_capacity
+    end
+
+    it "handles concurrent lookups safely" do
+      Kemal::RouteHandler::INSTANCE.cached_routes = Kemal::LRUCache(String, Radix::Result(Kemal::Route)).new(256)
+
+      get "/concurrent" do
+        "ok"
+      end
+
+      channel = Channel(Nil).new
+      fiber_count = 100
+      fiber_count.times do
+        spawn do
+          Kemal::RouteHandler::INSTANCE.lookup_route("GET", "/concurrent").found?.should be_true
+          channel.send(nil)
+        end
+      end
+      fiber_count.times { channel.receive }
+
+      Kemal::RouteHandler::INSTANCE.cached_routes.size.should eq 1
+    end
   end
 end

spec/router_spec.cr

@@ -0,0 +1,474 @@
+require "./spec_helper"
+
+describe "Kemal::Router" do
+  describe "basic routing" do
+    it "routes GET request with prefix" do
+      router = Kemal::Router.new
+      router.get "/users" do
+        "users list"
+      end
+
+      mount "/api", router
+
+      request = HTTP::Request.new("GET", "/api/users")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("users list")
+    end
+
+    it "routes POST request with prefix" do
+      router = Kemal::Router.new
+      router.post "/users" do
+        "user created"
+      end
+
+      mount "/api", router
+
+      request = HTTP::Request.new("POST", "/api/users")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("user created")
+    end
+
+    it "routes PUT request with prefix" do
+      router = Kemal::Router.new
+      router.put "/users/:id" do |env|
+        "user #{env.params.url["id"]} updated"
+      end
+
+      mount "/api", router
+
+      request = HTTP::Request.new("PUT", "/api/users/123")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("user 123 updated")
+    end
+
+    it "routes DELETE request with prefix" do
+      router = Kemal::Router.new
+      router.delete "/users/:id" do |env|
+        "user #{env.params.url["id"]} deleted"
+      end
+
+      mount "/api", router
+
+      request = HTTP::Request.new("DELETE", "/api/users/456")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("user 456 deleted")
+    end
+
+    it "routes PATCH request" do
+      router = Kemal::Router.new
+      router.patch "/users/:id" do
+        "user patched"
+      end
+
+      mount "/api", router
+
+      request = HTTP::Request.new("PATCH", "/api/users/1")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("user patched")
+    end
+
+    it "routes OPTIONS request" do
+      router = Kemal::Router.new
+      router.options "/users" do |env|
+        env.response.headers["Allow"] = "GET, POST, OPTIONS"
+        ""
+      end
+
+      mount "/api", router
+
+      request = HTTP::Request.new("OPTIONS", "/api/users")
+      client_response = call_request_on_app(request)
+      client_response.headers["Allow"].should eq("GET, POST, OPTIONS")
+    end
+
+    it "mounts router without prefix" do
+      router = Kemal::Router.new
+      router.get "/status" do
+        "ok"
+      end
+
+      mount router
+
+      request = HTTP::Request.new("GET", "/status")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("ok")
+    end
+
+    it "works alongside global DSL routes" do
+      # Global DSL route
+      get "/global" do
+        "global route"
+      end
+
+      # Router route
+      router = Kemal::Router.new
+      router.get "/local" do
+        "router route"
+      end
+
+      mount "/api", router
+
+      # Test global route
+      global_request = HTTP::Request.new("GET", "/global")
+      global_response = call_request_on_app(global_request)
+      global_response.body.should eq("global route")
+
+      # Test router route
+      router_request = HTTP::Request.new("GET", "/api/local")
+      router_response = call_request_on_app(router_request)
+      router_response.body.should eq("router route")
+    end
+  end
+
+  describe "router-scoped filters" do
+    it "applies before filter to router routes" do
+      router = Kemal::Router.new
+
+      router.before do |env|
+        env.set "filtered", "yes"
+      end
+
+      router.get "/test" do |env|
+        env.get("filtered").to_s
+      end
+
+      mount "/api", router
+
+      request = HTTP::Request.new("GET", "/api/test")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("yes")
+    end
+
+    it "applies after filter to router routes" do
+      router = Kemal::Router.new
+
+      router.after do |env|
+        env.response.headers["X-After-Filter"] = "applied"
+      end
+
+      router.get "/test" do
+        "test"
+      end
+
+      mount "/api", router
+
+      request = HTTP::Request.new("GET", "/api/test")
+      client_response = call_request_on_app(request)
+      client_response.headers["X-After-Filter"].should eq("applied")
+    end
+
+    it "applies method-specific before filter" do
+      router = Kemal::Router.new
+
+      router.before_post do |env|
+        env.set "method", "post"
+      end
+
+      router.post "/test" do |env|
+        env.get("method").to_s
+      end
+
+      router.get "/test" do |env|
+        env.get?("method").to_s
+      end
+
+      mount "/api", router
+
+      post_request = HTTP::Request.new("POST", "/api/test")
+      post_response = call_request_on_app(post_request)
+      post_response.body.should eq("post")
+    end
+
+    it "applies filter to specific path" do
+      router = Kemal::Router.new
+
+      router.before "/protected" do |env|
+        env.set "auth", "required"
+      end
+
+      router.get "/protected" do |env|
+        env.get("auth").to_s
+      end
+
+      router.get "/public" do |env|
+        env.get?("auth").to_s
+      end
+
+      mount "/api", router
+
+      protected_request = HTTP::Request.new("GET", "/api/protected")
+      protected_response = call_request_on_app(protected_request)
+      protected_response.body.should eq("required")
+    end
+
+    it "applies namespace filters only within the namespace" do
+      router = Kemal::Router.new
+
+      router.namespace "/admin" do
+        before do |env|
+          halt env, 401, "unauthorized" unless env.request.headers["X-Admin"]? == "true"
+        end
+
+        get "/dashboard" do |env|
+          env.get("path").to_s
+        end
+      end
+
+      router.get "/public" do |env|
+        env.get("path").to_s
+      end
+
+      mount "/api", router
+
+      before_all do |env|
+        env.set "path", env.request.path
+      end
+
+      get "/public" do |env|
+        env.get("path").to_s
+      end
+
+      unauthorized_request = HTTP::Request.new("GET", "/api/admin/dashboard")
+      unauthorized_response = call_request_on_app(unauthorized_request)
+      unauthorized_response.status_code.should eq(401)
+      unauthorized_response.body.should eq("unauthorized")
+
+      authorized_request = HTTP::Request.new(
+        "GET",
+        "/api/admin/dashboard",
+        headers: HTTP::Headers{"X-Admin" => "true"},
+      )
+      authorized_response = call_request_on_app(authorized_request)
+      authorized_response.status_code.should eq(200)
+      authorized_response.body.should eq("/api/admin/dashboard")
+
+      api_public_request = HTTP::Request.new("GET", "/api/public")
+      api_public_response = call_request_on_app(api_public_request)
+      api_public_response.status_code.should eq(200)
+      api_public_response.body.should eq("/api/public")
+
+      public_request = HTTP::Request.new("GET", "/public")
+      public_response = call_request_on_app(public_request)
+      public_response.status_code.should eq(200)
+      public_response.body.should eq("/public")
+    end
+  end
+
+  describe "nested routers" do
+    it "namespaces routes correctly" do
+      router = Kemal::Router.new
+
+      router.namespace "/users" do
+        get "/" do
+          "users index"
+        end
+
+        get "/:id" do |env|
+          "user #{env.params.url["id"]}"
+        end
+      end
+
+      mount "/api/v1", router
+
+      index_request = HTTP::Request.new("GET", "/api/v1/users")
+      index_response = call_request_on_app(index_request)
+      index_response.body.should eq("users index")
+
+      show_request = HTTP::Request.new("GET", "/api/v1/users/42")
+      show_response = call_request_on_app(show_request)
+      show_response.body.should eq("user 42")
+    end
+
+    it "supports multiple namespaces" do
+      router = Kemal::Router.new
+
+      router.namespace "/users" do
+        get "/" do
+          "users"
+        end
+      end
+
+      router.namespace "/posts" do
+        get "/" do
+          "posts"
+        end
+      end
+
+      mount "/api", router
+
+      users_request = HTTP::Request.new("GET", "/api/users")
+      users_response = call_request_on_app(users_request)
+      users_response.body.should eq("users")
+
+      posts_request = HTTP::Request.new("GET", "/api/posts")
+      posts_response = call_request_on_app(posts_request)
+      posts_response.body.should eq("posts")
+    end
+
+    it "supports deeply nested routers" do
+      router = Kemal::Router.new
+
+      router.namespace "/api" do
+        namespace "/v1" do
+          namespace "/users" do
+            get "/" do
+              "deeply nested users"
+            end
+          end
+        end
+      end
+
+      mount router
+
+      request = HTTP::Request.new("GET", "/api/v1/users")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("deeply nested users")
+    end
+
+    it "mounts sub-router with mount method" do
+      users_router = Kemal::Router.new
+      users_router.get "/" do
+        "users from sub-router"
+      end
+      users_router.get "/:id" do |env|
+        "user #{env.params.url["id"]} from sub-router"
+      end
+
+      api_router = Kemal::Router.new
+      api_router.mount "/users", users_router
+
+      mount "/api", api_router
+
+      index_request = HTTP::Request.new("GET", "/api/users")
+      index_response = call_request_on_app(index_request)
+      index_response.body.should eq("users from sub-router")
+
+      show_request = HTTP::Request.new("GET", "/api/users/99")
+      show_response = call_request_on_app(show_request)
+      show_response.body.should eq("user 99 from sub-router")
+    end
+
+    it "applies namespace filters correctly" do
+      router = Kemal::Router.new
+
+      router.namespace "/admin" do
+        before do |env|
+          env.set "admin", "true"
+        end
+
+        get "/dashboard" do |env|
+          "admin: #{env.get("admin")}"
+        end
+      end
+
+      mount router
+
+      request = HTTP::Request.new("GET", "/admin/dashboard")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("admin: true")
+    end
+  end
+
+  describe "websocket support" do
+    it "registers websocket route with prefix" do
+      router = Kemal::Router.new
+      router.ws "/chat" do |socket|
+        socket.send("connected")
+      end
+
+      mount "/ws", router
+
+      handler = Kemal::WebSocketHandler::INSTANCE
+      headers = HTTP::Headers{
+        "Upgrade"               => "websocket",
+        "Connection"            => "Upgrade",
+        "Sec-WebSocket-Key"     => "dGhlIHNhbXBsZSBub25jZQ==",
+        "Sec-WebSocket-Version" => "13",
+      }
+      request = HTTP::Request.new("GET", "/ws/chat", headers)
+
+      io_with_context = create_ws_request_and_return_io_and_context(handler, request)[0]
+      io_with_context.to_s.should contain("101 Switching Protocols")
+    end
+
+    it "websocket route with url parameters" do
+      router = Kemal::Router.new
+      router.ws "/room/:id" do |socket|
+        socket.send("room")
+      end
+
+      mount "/ws", router
+
+      handler = Kemal::WebSocketHandler::INSTANCE
+      headers = HTTP::Headers{
+        "Upgrade"               => "websocket",
+        "Connection"            => "Upgrade",
+        "Sec-WebSocket-Key"     => "dGhlIHNhbXBsZSBub25jZQ==",
+        "Sec-WebSocket-Version" => "13",
+      }
+      request = HTTP::Request.new("GET", "/ws/room/123", headers)
+
+      io_with_context = create_ws_request_and_return_io_and_context(handler, request)[0]
+      io_with_context.to_s.should contain("101 Switching Protocols")
+    end
+  end
+
+  describe "router with prefix" do
+    it "initializes router with prefix" do
+      router = Kemal::Router.new("/v2")
+      router.get "/status" do
+        "v2 status"
+      end
+
+      mount "/api", router
+
+      request = HTTP::Request.new("GET", "/api/v2/status")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("v2 status")
+    end
+  end
+
+  describe "edge cases" do
+    it "handles trailing slashes correctly" do
+      router = Kemal::Router.new
+      router.get "/users/" do
+        "users with trailing slash"
+      end
+
+      mount "/api/", router
+
+      request = HTTP::Request.new("GET", "/api/users/")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("users with trailing slash")
+    end
+
+    it "handles root path in namespace" do
+      router = Kemal::Router.new
+
+      router.namespace "/users" do
+        get "" do
+          "users root"
+        end
+      end
+
+      mount "/api", router
+
+      request = HTTP::Request.new("GET", "/api/users")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("users root")
+    end
+
+    it "returns non-string values as empty string" do
+      router = Kemal::Router.new
+      router.get "/number" do
+        42
+      end
+
+      mount router
+
+      request = HTTP::Request.new("GET", "/number")
+      client_response = call_request_on_app(request)
+      client_response.body.should eq("")
+    end
+  end
+end

spec/run_spec.cr

@@ -3,6 +3,10 @@ require "./spec_helper"
 private def run(code)
   code = <<-CR
     require "./src/kemal"
+
+    Kemal.config.env = "test"
+    Kemal.config.port = 8000
+
     #{code}
     CR
 
@@ -15,35 +19,56 @@ end
 
 describe "Run" do
   it "runs a code block after starting" do
-    run(<<-CR).should eq "started\nstopped\n"
-      Kemal.config.env = "test"
+    run(<<-CR).should contain("started")
+      Kemal.run do
+        log "started"
+      end
+      CR
+  end
+
+  it "runs a code block after stopping" do
+    run(<<-CR).should contain("stopped")
       Kemal.run do
-        puts "started"
         Kemal.stop
-        puts "stopped"
+        log "stopped"
       end
       CR
   end
 
   it "runs without a block being specified" do
     run(<<-CR).should contain "[test] Kemal is running in test mode."
-      Kemal.config.env = "test"
       Kemal.run
-      puts Kemal.config.running
+      Kemal.config.running
       CR
   end
 
+  it "applies shutdown_timeout during graceful shutdown" do
+    output = run(<<-'CRYSTAL')
+      Kemal.config.shutdown_timeout = 30.milliseconds
+      start = Time.monotonic
+
+      Kemal.run do
+        Kemal.stop
+      end
+
+      elapsed_ms = (Time.monotonic - start).total_milliseconds
+      puts "elapsed_ms=#{elapsed_ms}"
+      CRYSTAL
+
+    match = output.match!(/elapsed_ms=([0-9]+(?:\.[0-9]+)?)/)
+    match[1].to_f.should be >= 20.0
+  end
+
   it "allows custom HTTP::Server bind" do
     run(<<-CR).should contain "[test] Kemal is running in test mode."
-      Kemal.config.env = "test"
       Kemal.run do |config|
         server = config.server.not_nil!
 
         {% if flag?(:windows) %}
-          server.bind_tcp "127.0.0.1", 3000
+          server.bind_tcp "127.0.0.1", 8000
         {% else %}
-          server.bind_tcp "127.0.0.1", 3000, reuse_port: true
-          server.bind_tcp "0.0.0.0", 3001, reuse_port: true
+          server.bind_tcp "127.0.0.1", 8000, reuse_port: true
+          server.bind_tcp "0.0.0.0", 8001, reuse_port: true
         {% end %}
       end
       CR

spec/spec_helper.cr

@@ -26,6 +26,12 @@ class AnotherContextStorageType
   @name = "kemal-context"
 end
 
+class CustomExceptionType < Exception
+end
+
+class ChildCustomExceptionType < CustomExceptionType
+end
+
 add_context_storage_type(TestContextStorageType)
 add_context_storage_type(AnotherContextStorageType)
 
@@ -87,6 +93,6 @@ Spec.after_each do
   Kemal.config.clear
   Kemal::FilterHandler::INSTANCE.tree = Radix::Tree(Array(Kemal::FilterHandler::FilterBlock)).new
   Kemal::RouteHandler::INSTANCE.routes = Radix::Tree(Route).new
-  Kemal::RouteHandler::INSTANCE.cached_routes = Hash(String, Radix::Result(Route)).new
+  Kemal::RouteHandler::INSTANCE.cached_routes = Kemal::LRUCache(String, Radix::Result(Kemal::Route)).new(Kemal.config.max_route_cache_size)
   Kemal::WebSocketHandler::INSTANCE.routes = Radix::Tree(WebSocket).new
 end

spec/static/dir/nested/path/test.txt

@@ -0,0 +1,2 @@
+hello
+world

spec/static_file_handler_spec.cr

@@ -13,6 +13,7 @@ end
 
 describe Kemal::StaticFileHandler do
   file = File.open "#{__DIR__}/static/dir/test.txt"
+  File.open "#{__DIR__}/static/dir/nested/path/test.txt"
   file_size = file.size
 
   it "should serve a file with content type and etag" do
@@ -97,12 +98,12 @@ describe Kemal::StaticFileHandler do
   end
 
   it "should handle only GET and HEAD method" do
-    %w(GET HEAD).each do |method|
+    %w[GET HEAD].each do |method|
       response = handle HTTP::Request.new(method, "/dir/test.txt")
       response.status_code.should eq(200)
     end
 
-    %w(POST PUT DELETE).each do |method|
+    %w[POST PUT DELETE].each do |method|
       response = handle HTTP::Request.new(method, "/dir/test.txt")
       response.status_code.should eq(404)
       response = handle HTTP::Request.new(method, "/dir/test.txt"), false
@@ -112,36 +113,34 @@ describe Kemal::StaticFileHandler do
   end
 
   it "should send part of files when requested (RFC7233)" do
-    %w(POST PUT DELETE HEAD).each do |method|
-      headers = HTTP::Headers{"Range" => "0-100"}
+    %w[POST PUT DELETE HEAD].each do |method|
+      headers = HTTP::Headers{"Range" => "bytes=0-4"}
       response = handle HTTP::Request.new(method, "/dir/test.txt", headers)
       response.status_code.should_not eq(206)
-      response.headers.has_key?("Content-Range").should eq(false)
+      response.headers.has_key?("Content-Range").should be_false
     end
 
-    %w(GET).each do |method|
-      headers = HTTP::Headers{"Range" => "0-100"}
+    %w[GET].each do |method|
+      headers = HTTP::Headers{"Range" => "bytes=0-4"}
       response = handle HTTP::Request.new(method, "/dir/test.txt", headers)
-      response.status_code.should eq(206 || 200)
-      if response.status_code == 206
-        response.headers.has_key?("Content-Range").should eq true
-        match = response.headers["Content-Range"].match(/bytes (\d+)-(\d+)\/(\d+)/)
-        match.should_not be_nil
-        if match
-          start_range = match[1].to_i { 0 }
-          end_range = match[2].to_i { 0 }
-          range_size = match[3].to_i { 0 }
+      response.status_code.should eq(206)
+      response.headers.has_key?("Content-Range").should be_true
+      match = response.headers["Content-Range"].match(/bytes (\d+)-(\d+)\/(\d+)/)
+      match.should_not be_nil
+      if match
+        start_range = match[1].to_i { 0 }
+        end_range = match[2].to_i { 0 }
+        range_size = match[3].to_i { 0 }
 
-          range_size.should eq file_size
-          (end_range < file_size).should eq true
-          (start_range < end_range).should eq true
-        end
+        range_size.should eq file_size
+        (end_range < file_size).should be_true
+        (start_range < end_range).should be_true
       end
     end
   end
 
   it "should handle setting custom headers" do
-    headers = Proc(HTTP::Server::Context, String, File::Info, Void).new do |env, path, stat|
+    headers = Proc(HTTP::Server::Context, String, File::Info, Nil).new do |env, path, stat|
       if path =~ /\.html$/
         env.response.headers.add("Access-Control-Allow-Origin", "*")
       end
@@ -159,4 +158,30 @@ describe Kemal::StaticFileHandler do
     response = handle HTTP::Request.new("GET", "/dir/index.html")
     response.headers["Access-Control-Allow-Origin"].should eq("*")
   end
+
+  # Path Traversal Security Tests
+  it "should prevent path traversal attacks with .." do
+    response = handle HTTP::Request.new("GET", "/../../../etc/passwd")
+    response.status_code.should eq(302)
+  end
+
+  it "should prevent path traversal attacks with URL encoded .." do
+    response = handle HTTP::Request.new("GET", "/..%2f..%2f..%2fetc%2fpasswd")
+    response.status_code.should eq(302)
+  end
+
+  it "should prevent path traversal attacks with mixed .. and URL encoded .." do
+    response = handle HTTP::Request.new("GET", "/..%2f../..%2fetc%2fpasswd")
+    response.status_code.should eq(302)
+  end
+
+  it "should allow legitimate nested paths" do
+    response = handle HTTP::Request.new("GET", "/dir/nested/path/test.txt")
+    response.status_code.should eq(200)
+  end
+
+  it "should handle requests with trailing slashes in nested paths" do
+    response = handle HTTP::Request.new("GET", "/dir/nested/path/")
+    response.status_code.should eq(200)
+  end
 end

spec/view_spec.cr

@@ -1,7 +1,7 @@
 require "./spec_helper"
 
 macro render_with_base_and_layout(filename)
-  render "#{__DIR__}/asset/#{{{filename}}}", "#{__DIR__}/asset/layout.ecr"
+  render "#{__DIR__}/asset/#{{{ filename }}}", "#{__DIR__}/asset/layout.ecr"
 end
 
 describe "Views" do
@@ -38,8 +38,8 @@ describe "Views" do
   it "renders layout with variables" do
     get "/view/:name" do |env|
       name = env.params.url["name"]
-      var1 = "serdar"
-      var2 = "kemal"
+      var1 = "serdar" # ameba:disable Lint/UselessAssign
+      var2 = "kemal"  # ameba:disable Lint/UselessAssign
       render "#{__DIR__}/asset/hello_with_content_for.ecr", "#{__DIR__}/asset/layout_with_yield_and_vars.ecr"
     end
     request = HTTP::Request.new("GET", "/view/world")

src/kemal.cr

@@ -1,24 +1,27 @@
 require "http"
 require "json"
+require "log"
 require "uri"
 require "./kemal/*"
 require "./kemal/ext/*"
 require "./kemal/helpers/*"
 
 module Kemal
+  Log = ::Log.for(self)
+
   # Overload of `self.run` with the default startup logging.
   def self.run(port : Int32?, args = ARGV, trap_signal : Bool = true)
-    self.run(port, args, trap_signal) { }
+    run(port, args, trap_signal) { }
   end
 
   # Overload of `self.run` without port.
   def self.run(args = ARGV, trap_signal : Bool = true)
-    self.run(nil, args: args, trap_signal: trap_signal)
+    run(nil, args: args, trap_signal: trap_signal)
   end
 
   # Overload of `self.run` to allow just a block.
   def self.run(args = ARGV, &block)
-    self.run(nil, args: args, trap_signal: true, &block)
+    run(nil, args: args, trap_signal: true, &block)
   end
 
   # The command to run a `Kemal` application.
@@ -46,41 +49,46 @@ module Kemal
     yield config
 
     # Abort if block called `Kemal.stop`
-    return unless config.running
+    return if !config.running
 
-    unless server.each_address { |_| break true }
-      {% if flag?(:without_openssl) %}
-        server.bind_tcp(config.host_binding, config.port)
-      {% else %}
-        if ssl = config.ssl
-          server.bind_tls(config.host_binding, config.port, ssl)
-        else
+    if config.env != "test"
+      if !server.each_address { |_| break true }
+        {% if flag?(:without_openssl) %}
           server.bind_tcp(config.host_binding, config.port)
-        end
-      {% end %}
+        {% else %}
+          if ssl = config.ssl
+            server.bind_tls(config.host_binding, config.port, ssl)
+          else
+            server.bind_tcp(config.host_binding, config.port)
+          end
+        {% end %}
+      end
     end
 
     display_startup_message(config, server)
 
-    server.listen unless config.env == "test"
+    server.listen if config.env != "test"
   end
 
   def self.display_startup_message(config, server)
     if config.env != "test"
       addresses = server.addresses.join ", " { |address| "#{config.scheme}://#{address}" }
-      log "[#{config.env}] #{config.app_name} is ready to lead at #{addresses}"
+      Log.info { "[#{config.env}] #{config.app_name} is ready to lead at #{addresses}" }
     else
-      log "[#{config.env}] #{config.app_name} is running in test mode. Server not listening"
+      Log.info { "[#{config.env}] #{config.app_name} is running in test mode. Server not listening" }
     end
   end
 
   def self.stop
-    raise "#{Kemal.config.app_name} is already stopped." if !config.running
+    raise "#{Kemal.config.app_name} is already stopped. Cannot stop an already stopped server." if !config.running
     if server = config.server
       server.close unless server.closed?
       config.running = false
+      if config.shutdown_timeout.positive?
+        sleep(config.shutdown_timeout)
+      end
     else
-      raise "Kemal.config.server is not set. Please use Kemal.run to set the server."
+      raise "Cannot stop #{Kemal.config.app_name}: server instance is not set. Please ensure Kemal.run has been called before calling Kemal.stop."
     end
   end
 
@@ -94,7 +102,7 @@ module Kemal
 
   private def self.setup_trap_signal
     Process.on_terminate do
-      log "#{Kemal.config.app_name} is going to take a rest!" if Kemal.config.shutdown_message
+      Log.info { "#{Kemal.config.app_name} is going to take a rest!" } if Kemal.config.shutdown_message
       Kemal.stop
       exit
     end

src/kemal/cli.cr

@@ -42,11 +42,11 @@ module Kemal
     private def configure_ssl
       {% if !flag?(:without_openssl) %}
         if @ssl_enabled
-          abort "SSL Key Not Found" if !@key_file
-          abort "SSL Certificate Not Found" if !@cert_file
+          abort "SSL configuration error: SSL key file not specified. Use --ssl-key-file FILE to specify the key file." if @key_file.empty?
+          abort "SSL configuration error: SSL certificate file not specified. Use --ssl-cert-file FILE to specify the certificate file." if @cert_file.empty?
           ssl = Kemal::SSL.new
-          ssl.key_file = @key_file.not_nil!
-          ssl.cert_file = @cert_file.not_nil!
+          ssl.key_file = @key_file
+          ssl.cert_file = @cert_file
           Kemal.config.ssl = ssl.context
         end
       {% end %}

src/kemal/config.cr

@@ -8,11 +8,12 @@ module Kemal
   # Kemal.config
   # ```
   class Config
-    INSTANCE        = Config.new
-    HANDLERS        = [] of HTTP::Handler
-    CUSTOM_HANDLERS = [] of Tuple(Nil | Int32, HTTP::Handler)
-    FILTER_HANDLERS = [] of HTTP::Handler
-    ERROR_HANDLERS  = {} of Int32 => HTTP::Server::Context, Exception -> String
+    INSTANCE           = Config.new
+    HANDLERS           = [] of HTTP::Handler
+    CUSTOM_HANDLERS    = [] of Tuple(Int32?, HTTP::Handler)
+    FILTER_HANDLERS    = [] of HTTP::Handler
+    ERROR_HANDLERS     = {} of Int32 => HTTP::Server::Context, Exception -> String
+    EXCEPTION_HANDLERS = {} of Exception.class => HTTP::Server::Context, Exception -> String
 
     {% if flag?(:without_openssl) %}
       @ssl : Bool?
@@ -21,10 +22,12 @@ module Kemal
     {% end %}
 
     property app_name, host_binding, ssl, port, env, public_folder, logging, running
-    property always_rescue, server : HTTP::Server?, extra_options, shutdown_message
+    property always_rescue, server : HTTP::Server?, extra_options, shutdown_message, shutdown_timeout
     property serve_static : (Bool | Hash(String, Bool))
-    property static_headers : (HTTP::Server::Context, String, File::Info -> Void)?
+    property static_headers : (HTTP::Server::Context, String, File::Info ->)?
     property? powered_by_header : Bool = true
+    property max_route_cache_size : Int32
+    property max_request_body_size : Int32
 
     def initialize
       @app_name = "Kemal"
@@ -41,13 +44,23 @@ module Kemal
       @default_handlers_setup = false
       @running = false
       @shutdown_message = true
+      @shutdown_timeout = 0.seconds
       @handler_position = 0
+      @max_route_cache_size = 1024
+      @max_request_body_size = 8 * 1024 * 1024 # 8MB
     end
 
+    @[Deprecated("Use standard library Log")]
     def logger
-      @logger.not_nil!
+      @logger || NullLogHandler.new
     end
 
+    # :nodoc:
+    def logger?
+      @logger
+    end
+
+    @[Deprecated("Use standard library Log")]
     def logger=(logger : Kemal::BaseLogHandler)
       @logger = logger
     end
@@ -61,10 +74,13 @@ module Kemal
       @router_included = false
       @handler_position = 0
       @default_handlers_setup = false
+      @max_route_cache_size = 1024
+      @max_request_body_size = 8 * 1024 * 1024
       HANDLERS.clear
       CUSTOM_HANDLERS.clear
       FILTER_HANDLERS.clear
       ERROR_HANDLERS.clear
+      EXCEPTION_HANDLERS.clear
     end
 
     def handlers
@@ -88,14 +104,26 @@ module Kemal
       FILTER_HANDLERS << handler
     end
 
+    # Returns the defined error handlers for HTTP status codes
     def error_handlers
       ERROR_HANDLERS
     end
 
+    # Adds an error handler for the given HTTP status code
     def add_error_handler(status_code : Int32, &handler : HTTP::Server::Context, Exception -> _)
       ERROR_HANDLERS[status_code] = ->(context : HTTP::Server::Context, error : Exception) { handler.call(context, error).to_s }
     end
 
+    # Returns the defined error handlers for exceptions
+    def exception_handlers
+      EXCEPTION_HANDLERS
+    end
+
+    # Adds an error handler for the given exception
+    def add_exception_handler(exception : Exception.class, &handler : HTTP::Server::Context, Exception -> _)
+      EXCEPTION_HANDLERS[exception] = ->(context : HTTP::Server::Context, error : Exception) { handler.call(context, error).to_s }
+    end
+
     def extra_options(&@extra_options : OptionParser ->)
     end
 
@@ -121,12 +149,11 @@ module Kemal
     end
 
     private def setup_log_handler
-      @logger ||= if @logging
-                    Kemal::LogHandler.new
-                  else
-                    Kemal::NullLogHandler.new
-                  end
-      HANDLERS.insert(@handler_position, @logger.not_nil!)
+      return unless @logging
+
+      log_handler = @logger || Kemal::RequestLogHandler.new
+
+      HANDLERS.insert(@handler_position, log_handler)
       @handler_position += 1
     end
 
@@ -137,8 +164,8 @@ module Kemal
 
     private def setup_error_handler
       if @always_rescue
-        @error_handler ||= Kemal::ExceptionHandler.new
-        HANDLERS.insert(@handler_position, @error_handler.not_nil!)
+        handler = @error_handler ||= Kemal::ExceptionHandler.new
+        HANDLERS.insert(@handler_position, handler)
         @handler_position += 1
       end
     end

src/kemal/dsl.cr

@@ -1,43 +1,195 @@
 # Kemal DSL is defined here and it's baked into global scope.
+# These methods are available globally in your application.
 #
-# The DSL currently consists of:
+# ## Available DSL Methods
 #
-# - get post put patch delete options
-# - WebSocket(ws)
-# - before_*
-# - error
+# - **HTTP Routes**: `get`, `post`, `put`, `patch`, `delete`, `options`
+# - **WebSocket**: `ws`
+# - **Filters**: `before_all`, `before_get`, `after_all`, `after_get`, etc.
+# - **Error Handling**: `error`
+# - **Modular Routing**: `mount`
 HTTP_METHODS   = %w(get post put patch delete options head)
 FILTER_METHODS = %w(get post put patch delete options head all)
 
+# Defines a route for the given HTTP method.
+#
+# NOTE: The path must start with a `/`.
+#
+# ```
+# get "/hello" do |env|
+#   "Hello World!"
+# end
+#
+# post "/users" do |env|
+#   "User created"
+# end
+# ```
 {% for method in HTTP_METHODS %}
-  def {{method.id}}(path : String, &block : HTTP::Server::Context -> _)
-    raise Kemal::Exceptions::InvalidPathStartException.new({{method}}, path) unless Kemal::Utils.path_starts_with_slash?(path)
-    Kemal::RouteHandler::INSTANCE.add_route({{method}}.upcase, path, &block)
+  def {{ method.id }}(path : String, &block : HTTP::Server::Context -> _)
+    raise Kemal::Exceptions::InvalidPathStartException.new({{ method }}, path) unless Kemal::Utils.path_starts_with_slash?(path)
+    Kemal::RouteHandler::INSTANCE.add_route({{ method }}.upcase, path, &block)
   end
 {% end %}
 
-def ws(path : String, &block : HTTP::WebSocket, HTTP::Server::Context -> Void)
+# Defines a WebSocket route.
+#
+# NOTE: The path must start with a `/`.
+#
+# ```
+# ws "/chat" do |socket, env|
+#   socket.on_message do |msg|
+#     socket.send "Echo: #{msg}"
+#   end
+# end
+# ```
+def ws(path : String, &block : HTTP::WebSocket, HTTP::Server::Context ->)
   raise Kemal::Exceptions::InvalidPathStartException.new("ws", path) unless Kemal::Utils.path_starts_with_slash?(path)
   Kemal::WebSocketHandler::INSTANCE.add_route path, &block
 end
 
+# Defines an error handler for the given HTTP status code.
+#
+# ```
+# error 404 do |env|
+#   "Page not found"
+# end
+# ```
 def error(status_code : Int32, &block : HTTP::Server::Context, Exception -> _)
   Kemal.config.add_error_handler status_code, &block
 end
 
-# All the helper methods available are:
-#  - before_all, before_get, before_post, before_put, before_patch, before_delete, before_options
-#  - after_all, after_get, after_post, after_put, after_patch, after_delete, after_options
+# Defines an error handler for the given `HTTP::Status`.
+#
+# ```
+# error :not_found do |env|
+#   "Page not found"
+# end
+# ```
+def error(status : HTTP::Status, &block : HTTP::Server::Context, Exception -> _)
+  Kemal.config.add_error_handler status.code, &block
+end
+
+# Defines an error handler for the given exception type.
+#
+# ```
+# error MyCustomException do |env, ex|
+#   "Error: #{ex.message}"
+# end
+# ```
+def error(exception : Exception.class, &block : HTTP::Server::Context, Exception -> _)
+  Kemal.config.add_exception_handler exception, &block
+end
+
+# Defines filters that run before or after requests.
+#
+# Available methods:
+# - `before_all`, `before_get`, `before_post`, `before_put`, `before_patch`, `before_delete`, `before_options`
+# - `after_all`, `after_get`, `after_post`, `after_put`, `after_patch`, `after_delete`, `after_options`
+#
+# ```
+# before_all do |env|
+#   env.response.content_type = "application/json"
+# end
+#
+# before_get "/admin/*" do |env|
+#   # Authentication check
+# end
+#
+# # Multiple paths
+# after_post ["/users", "/posts"] do |env|
+#   # Logging
+# end
+# ```
 {% for type in ["before", "after"] %}
   {% for method in FILTER_METHODS %}
-    def {{type.id}}_{{method.id}}(path : String = "*", &block : HTTP::Server::Context -> _)
-     Kemal::FilterHandler::INSTANCE.{{type.id}}({{method}}.upcase, path, &block)
+    def {{ type.id }}_{{ method.id }}(path : String = "*", &block : HTTP::Server::Context -> _)
+     Kemal::FilterHandler::INSTANCE.{{ type.id }}({{ method }}.upcase, path, &block)
     end
 
-    def {{type.id}}_{{method.id}}(paths : Array(String), &block : HTTP::Server::Context -> _)
+    def {{ type.id }}_{{ method.id }}(paths : Enumerable(String), &block : HTTP::Server::Context -> _)
       paths.each do |path|
-        Kemal::FilterHandler::INSTANCE.{{type.id}}({{method}}.upcase, path, &block)
+        Kemal::FilterHandler::INSTANCE.{{ type.id }}({{ method }}.upcase, path, &block)
       end
     end
   {% end %}
 {% end %}
+
+# Adds a `HTTP::Handler` (middleware) to the handler chain.
+# The handler runs for all requests.
+#
+# ```
+# use MyHandler.new
+# ```
+def use(handler : HTTP::Handler)
+  Kemal.config.add_handler(handler)
+end
+
+# Adds a `HTTP::Handler` (middleware) at a specific position in the handler chain.
+#
+# ```
+# use MyHandler.new, position: 1
+# ```
+def use(handler : HTTP::Handler, position : Int32)
+  Kemal.config.add_handler(handler, position)
+end
+
+# Adds a `HTTP::Handler` (middleware) that only runs for requests matching the path prefix.
+#
+# ```
+# use "/api", AuthHandler.new
+# ```
+#
+# The handler will execute for:
+# - Exact match: `/api`
+# - Prefix match: `/api/users`, `/api/posts/1`
+#
+# But NOT for:
+# - `/`, `/apiv2`, `/other`
+def use(path : String, handler : HTTP::Handler)
+  Kemal.config.add_handler(Kemal::PathHandler.new(path, handler))
+end
+
+# Adds multiple `HTTP::Handler` (middlewares) for a specific path prefix.
+#
+# ```
+# use "/api", [AuthHandler.new, RateLimiter.new, CorsHandler.new]
+# ```
+def use(path : String, handlers : Enumerable(HTTP::Handler))
+  handlers.each do |handler|
+    use(path, handler)
+  end
+end
+
+# Mounts a router without additional prefix.
+#
+# ```
+# api = Kemal::Router.new
+# api.get "/users" do |env|
+#   "users"
+# end
+#
+# mount api
+# # Result: GET /users
+# ```
+def mount(router : Kemal::Router)
+  router.register_routes
+end
+
+# Mounts a router at the given *path* prefix.
+#
+# NOTE: The path must start with a `/`.
+#
+# All routes defined in the router will be prefixed with the given path.
+#
+# ```
+# api = Kemal::Router.new
+# api.get "/users" do |env|
+#   "users"
+# end
+#
+# mount "/api/v1", api
+# # Result: GET /api/v1/users
+# ```
+def mount(path : String, router : Kemal::Router)
+  router.register_routes(path)
+end

src/kemal/exception_handler.cr

@@ -10,13 +10,44 @@ module Kemal
       call_exception_with_status_code(context, ex, 404)
     rescue ex : Kemal::Exceptions::CustomException
       call_exception_with_status_code(context, ex, context.response.status_code)
+    rescue ex : Kemal::Exceptions::PayloadTooLarge
+      call_exception_with_status_code(context, ex, 413)
     rescue ex : Exception
-      log("Exception: #{ex.inspect_with_backtrace}")
+      # Matches an error handler for the given exception
+      #
+      # Matches based on order of declaration rather than inheritance relationship
+      # for child exceptions
+      Kemal.config.exception_handlers.each do |expected_exception, handler|
+        if ex.class <= expected_exception
+          return call_exception_with_exception(context, ex, handler, 500)
+        end
+      end
+
+      Log.error(exception: ex) { ex.message }
+      # Else use generic 500 handler if defined
       return call_exception_with_status_code(context, ex, 500) if Kemal.config.error_handlers.has_key?(500)
       verbosity = Kemal.config.env == "production" ? false : true
       render_500(context, ex, verbosity)
     end
 
+    # Calls the given error handler with the current exception
+    #
+    # The logic for validating that the current exception should be handled
+    # by the given error handler should be done by the caller of this method.
+    private def call_exception_with_exception(
+      context : HTTP::Server::Context,
+      exception : Exception,
+      handler : Proc(HTTP::Server::Context, Exception, String),
+      status_code : Int32 = 500,
+    )
+      return if context.response.closed?
+
+      context.response.content_type = "text/html" unless context.response.headers.has_key?("Content-Type")
+      context.response.status_code = status_code
+      context.response.print handler.call(context, exception)
+      context
+    end
+
     private def call_exception_with_status_code(context : HTTP::Server::Context, exception : Exception, status_code : Int32)
       return if context.response.closed?
       if !Kemal.config.error_handlers.empty? && Kemal.config.error_handlers.has_key?(status_code)

src/kemal/ext/context.cr

@@ -11,11 +11,16 @@ class HTTP::Server
     macro finished
       alias StoreTypes = Union({{ STORE_MAPPINGS.splat }})
       @store = {} of String => StoreTypes
+      @cached_route_lookup : Radix::Result(Kemal::Route)?
+      @cached_ws_route_lookup : Radix::Result(Kemal::WebSocket)?
     end
 
+    # Optimized: Use cached lookup results to avoid redundant route lookups
+    # when params is accessed after route_found? or route has already been called
     def params
-      if ws_route_found?
-        @params ||= Kemal::ParamParser.new(@request, ws_route_lookup.params)
+      ws_lookup = ws_route_lookup
+      if ws_lookup.found?
+        @params ||= Kemal::ParamParser.new(@request, ws_lookup.params)
       else
         @params ||= Kemal::ParamParser.new(@request, route_lookup.params)
       end
@@ -36,16 +41,31 @@ class HTTP::Server
       ws_route_lookup.payload
     end
 
+    # Optimized: Cache route lookup result to avoid redundant lookups
+    # when called multiple times (e.g., route_found?, route, params)
     def route_lookup
-      Kemal::RouteHandler::INSTANCE.lookup_route(@request.method.as(String), @request.path)
+      @cached_route_lookup ||= Kemal::RouteHandler::INSTANCE.lookup_route(@request.method.as(String), @request.path)
+    end
+
+    # Clears the cached route lookup and updates params with new route. Used by handlers that
+    # modify the request (e.g. OverrideMethodHandler) so the next route lookup uses the updated request.
+    def invalidate_route_cache
+      @cached_route_lookup = nil
+      params = @params
+      if params
+        new_lookup = Kemal::RouteHandler::INSTANCE.lookup_route(@request.method.as(String), @request.path)
+        @cached_route_lookup = new_lookup
+        params.update_url_params(new_lookup.params)
+      end
     end
 
     def route_found?
       route_lookup.found?
     end
 
+    # Optimized: Cache websocket route lookup result to avoid redundant lookups
     def ws_route_lookup
-      Kemal::WebSocketHandler::INSTANCE.lookup_ws_route(@request.path)
+      @cached_ws_route_lookup ||= Kemal::WebSocketHandler::INSTANCE.lookup_ws_route(@request.path)
     end
 
     def ws_route_found?
@@ -63,5 +83,99 @@ class HTTP::Server
     def get?(name : String)
       @store[name]?
     end
+
+    # Sets the response status code and returns self for chaining.
+    #
+    # ```
+    # get "/users/:id" do |env|
+    #   if user = User.find?(env.params.url["id"])
+    #     env.json(user)
+    #   else
+    #     env.status(404).json({error: "User not found"})
+    #   end
+    # end
+    # ```
+    def status(code : Int32) : self
+      @response.status_code = code
+      self
+    end
+
+    # Sets the response status from an *HTTP::Status* and returns self for chaining.
+    #
+    # ```
+    # get "/users/:id" do |env|
+    #   env.status(:not_found).json({error: "User not found"})
+    # end
+    #
+    # post "/users" do |env|
+    #   env.status(:created).json({id: 1})
+    # end
+    # ```
+    def status(status : HTTP::Status) : self
+      @response.status = status
+      self
+    end
+
+    # Sends a JSON response with the proper `Content-Type` header.
+    # Serializes the data to a string and writes it to the response in a single operation.
+    # Use *content_type* for custom types (e.g. `application/vnd.api+json` for JSON API).
+    #
+    # ```
+    # get "/users" do |env|
+    #   env.json({users: ["alice", "bob"]})
+    # end
+    #
+    # post "/users" do |env|
+    #   env.status(201).json({created: true})
+    # end
+    #
+    # # JSON API
+    # get "/api/users" do |env|
+    #   env.json({data: users}, content_type: "application/vnd.api+json")
+    # end
+    # ```
+    def json(data, *, content_type : String = "application/json") : Nil
+      @response.content_type = content_type
+      @response << data.to_json
+    end
+
+    # Sends an HTML response with the proper `Content-Type` header.
+    # Serializes the content to a string and writes it to the response in a single operation.
+    #
+    # ```
+    # get "/" do |env|
+    #   env.html("<h1>Welcome</h1>")
+    # end
+    # ```
+    def html(content : String, *, content_type : String = "text/html; charset=utf-8") : Nil
+      @response.content_type = content_type
+      @response << content
+    end
+
+    # Sends a plain text response with the proper `Content-Type` header.
+    # Serializes the content to a string and writes it to the response in a single operation.
+    #
+    # ```
+    # get "/health" do |env|
+    #   env.text("OK")
+    # end
+    # ```
+    def text(content : String, *, content_type : String = "text/plain; charset=utf-8") : Nil
+      @response.content_type = content_type
+      @response << content
+    end
+
+    # Sends an XML response with the proper `Content-Type` header.
+    # Serializes the content to a string and writes it to the response in a single operation.
+    #
+    # ```
+    # get "/feed.xml" do |env|
+    #   env.xml("<?xml version=\"1.0\"?><rss>...</rss>")
+    # end
+    # ```
+    def xml(content : String, *, content_type : String = "application/xml; charset=utf-8") : Nil
+      @response.content_type = content_type
+      @response << content
+    end
   end
 end

src/kemal/file_upload.cr

@@ -20,5 +20,10 @@ module Kemal
       @read_time = upload.read_time
       @size = upload.size
     end
+
+    def cleanup
+      @tempfile.close
+      ::File.delete(@tempfile.path) if ::File.exists?(@tempfile.path)
+    end
   end
 end

src/kemal/filter_handler.cr

@@ -3,17 +3,41 @@ module Kemal
   class FilterHandler
     include HTTP::Handler
     INSTANCE = new
-    property tree
+
+    # Path used to represent wildcard filters that apply to all routes
+    private WILDCARD_PATH = "*"
+
+    @tree : Radix::Tree(Array(FilterBlock))
+
+    # Hash cache for exact path filters to avoid repeated tree lookups
+    # Key format: "/#{type}/#{verb}/#{path}" (e.g., "/before/ALL/*")
+    @exact_filters : Hash(String, Array(FilterBlock))
+
+    def tree
+      @tree
+    end
+
+    def tree=(tree : Radix::Tree(Array(FilterBlock)))
+      @tree = tree
+      @exact_filters = Hash(String, Array(FilterBlock)).new
+    end
 
     # This middleware is lazily instantiated and added to the handlers as soon as a call to `after_X` or `before_X` is made.
     def initialize
       @tree = Radix::Tree(Array(FilterBlock)).new
+      @exact_filters = Hash(String, Array(FilterBlock)).new
       Kemal.config.add_filter_handler(self)
     end
 
     # The call order of the filters is `before_all -> before_x -> X -> after_x -> after_all`.
     def call(context : HTTP::Server::Context)
-      return call_next(context) unless context.route_found?
+      if !context.route_found?
+        if Kemal.config.error_handlers.has_key?(404)
+          call_block_for_path_type("ALL", context.request.path, :before, context)
+        end
+        return call_next(context)
+      end
+
       call_block_for_path_type("ALL", context.request.path, :before, context)
       call_block_for_path_type(context.request.method, context.request.path, :before, context)
       if Kemal.config.error_handlers.has_key?(context.response.status_code)
@@ -25,15 +49,21 @@ module Kemal
       context
     end
 
-    # :nodoc: This shouldn't be called directly, it's not private because
-    # I need to call it for testing purpose since I can't call the macros in the spec.
-    # It adds the block for the corresponding verb/path/type combination to the tree.
+    # :nodoc:
+    # This shouldn't be called directly, it's not private because I need to call it for testing purpose since I can't call the macros in the spec.
+    #
+    # Registers a filter block for the given verb/path/type combination.
+    # Uses @exact_filters hash for O(1) lookup when adding multiple filters to the same path.
     def _add_route_filter(verb : String, path, type, &block : HTTP::Server::Context -> _)
-      lookup = lookup_filters_for_path_type(verb, path, type)
-      if lookup.found? && lookup.payload.is_a?(Array(FilterBlock))
-        lookup.payload << FilterBlock.new(&block)
+      key = radix_path(verb, path, type)
+
+      if filters = @exact_filters[key]?
+        filters << FilterBlock.new(&block)
       else
-        @tree.add radix_path(verb, path, type), [FilterBlock.new(&block)]
+        filters = [FilterBlock.new(&block)]
+        @exact_filters[key] = filters
+
+        @tree.add key, filters
       end
     end
 
@@ -51,8 +81,24 @@ module Kemal
       _add_route_filter verb, path, :after, &block
     end
 
-    # This will fetch the block for the verb/path/type from the tree and call it.
+    # Executes filters for a given path, ensuring global wildcard filters run first.
+    #
+    # Execution order:
+    # 1. Global wildcard filters ("*") - if path is not already a wildcard
+    # 2. Exact path filters - filters registered for the specific path
+    #
+    # This ensures that global filters (like `before_all`) always execute,
+    # while namespace-specific filters only apply to their registered paths.
     private def call_block_for_path_type(verb : String?, path : String, type, context : HTTP::Server::Context)
+      if path != WILDCARD_PATH
+        call_block_for_exact_path_type(verb, "*", type, context)
+      end
+
+      # Executes all filter blocks registered for a specific verb/path/type combination
+      call_block_for_exact_path_type(verb, path, type, context)
+    end
+
+    private def call_block_for_exact_path_type(verb : String?, path : String, type, context : HTTP::Server::Context)
       lookup = lookup_filters_for_path_type(verb, path, type)
       if lookup.found? && lookup.payload.is_a? Array(FilterBlock)
         blocks = lookup.payload

src/kemal/handler.cr

@@ -1,27 +1,34 @@
 module Kemal
-  # `Kemal::Handler` is a subclass of `HTTP::Handler`.
+  # Kemal::HandlerInterface provides helpful methods for use in middleware creation
   #
-  # It adds `only`, `only_match?`, `exclude`, `exclude_match?`.
-  # These methods are useful for the conditional execution of custom handlers .
-  class Handler
+  # More specifically, `only`, `only_match?`, `exclude`, `exclude_match?`
+  # allows one to define the conditional execution of custom handlers.
+  #
+  # To use, simply `include` it within your type.
+  #
+  # It is an implementation of `HTTP::Handler` and can be used anywhere that
+  # requests an `HTTP::Handler` type.
+  module HandlerInterface
     include HTTP::Handler
 
-    @@only_routes_tree = Radix::Tree(String).new
-    @@exclude_routes_tree = Radix::Tree(String).new
+    macro included
+      @@only_routes_tree = Radix::Tree(String).new
+      @@exclude_routes_tree = Radix::Tree(String).new
+    end
 
     macro only(paths, method = "GET")
-      class_name = {{@type.name}}
-      class_name_method = "#{class_name}/#{{{method}}}"
-      ({{paths}}).each do |path|
-        @@only_routes_tree.add class_name_method + path, '/' + {{method}} + path
+      class_name = {{ @type.name }}
+      class_name_method = "#{class_name}/#{{{ method }}}"
+      ({{ paths }}).each do |path|
+        @@only_routes_tree.add class_name_method + path, '/' + {{ method }} + path
       end
     end
 
     macro exclude(paths, method = "GET")
-      class_name = {{@type.name}}
-      class_name_method = "#{class_name}/#{{{method}}}"
-      ({{paths}}).each do |path|
-        @@exclude_routes_tree.add class_name_method + path, '/' + {{method}} + path
+      class_name = {{ @type.name }}
+      class_name_method = "#{class_name}/#{{{ method }}}"
+      ({{ paths }}).each do |path|
+        @@exclude_routes_tree.add class_name_method + path, '/' + {{ method }} + path
       end
     end
 
@@ -75,4 +82,13 @@ module Kemal
       "#{self.class}/#{method}#{path}"
     end
   end
+
+  # `Kemal::Handler` is an implementation of `HTTP::Handler`.
+  #
+  # It includes `HandlerInterface` to add the methods
+  # `only`, `only_match?`, `exclude`, `exclude_match?`.
+  # These methods are useful for the conditional execution of custom handlers .
+  class Handler
+    include HandlerInterface
+  end
 end

src/kemal/helpers/exception_page.cr

@@ -32,7 +32,7 @@ module Kemal
           <p>Something wrong with the server :(</p>
         </body>
         </html>
-      HTML
+        HTML
     end
   end
 end

src/kemal/helpers/exceptions.cr

@@ -18,4 +18,10 @@ module Kemal::Exceptions
       super message
     end
   end
+
+  class PayloadTooLarge < Exception
+    def initialize
+      super "Payload Too Large"
+    end
+  end
 end

src/kemal/helpers/helpers.cr

@@ -15,10 +15,12 @@ require "mime"
 # - `Kemal::StaticFileHandler`
 # - Here goes custom handlers
 # - `Kemal::RouteHandler`
+@[Deprecated("Use `use` instead")]
 def add_handler(handler : HTTP::Handler)
   Kemal.config.add_handler handler
 end
 
+@[Deprecated("Use `use` with position parameter instead")]
 def add_handler(handler : HTTP::Handler, position : Int32)
   Kemal.config.add_handler handler, position
 end
@@ -32,8 +34,14 @@ end
 
 # Logs the output via `logger`.
 # This is the built-in `Kemal::LogHandler` by default which uses STDOUT.
+@[Deprecated("Use standard library Log")]
 def log(message : String)
-  Kemal.config.logger.write "#{message}\n"
+  logger = Kemal.config.logger?
+  if logger
+    logger.write "#{message}\n"
+  else
+    Log.info { message }
+  end
 end
 
 # Enables / Disables logging.
@@ -70,6 +78,7 @@ end
 # ```
 # logger MyCustomLogger.new
 # ```
+@[Deprecated("Use standard library Log")]
 def logger(logger : Kemal::BaseLogHandler)
   Kemal.config.logger = logger
 end
@@ -205,31 +214,68 @@ end
 private def multipart(file, env : HTTP::Server::Context)
   # See http://httpwg.org/specs/rfc7233.html
   fileb = file.size
-  startb = endb = 0_i64
+  ranges = parse_ranges(env.request.headers["Range"]?, fileb)
 
-  if match = env.request.headers["Range"].match /bytes=(\d{1,})-(\d{0,})/
-    startb = match[1].to_i64 { 0_i64 } if match.size >= 2
-    endb = match[2].to_i64 { 0_i64 } if match.size >= 3
+  if ranges.empty?
+    env.response.content_length = fileb
+    env.response.status_code = 200 # Range not satisfiable
+    IO.copy(file, env.response)
+    return
   end
 
-  endb = fileb - 1 if endb == 0
-
-  if startb < endb < fileb
+  if ranges.size == 1
+    # Single range - send as regular partial content
+    startb, endb = ranges[0]
     content_length = 1_i64 + endb - startb
     env.response.status_code = 206
     env.response.content_length = content_length
     env.response.headers["Accept-Ranges"] = "bytes"
-    env.response.headers["Content-Range"] = "bytes #{startb}-#{endb}/#{fileb}" # MUST
+    env.response.headers["Content-Range"] = "bytes #{startb}-#{endb}/#{fileb}"
 
     file.seek(startb)
     IO.copy(file, env.response, content_length)
   else
-    env.response.content_length = fileb
-    env.response.status_code = 200 # Range not satisfable, see 4.4 Note
-    IO.copy(file, env.response)
+    # Multiple ranges - send as multipart/byteranges
+    boundary = "kemal-#{Random::Secure.hex(16)}"
+    env.response.content_type = "multipart/byteranges; boundary=#{boundary}"
+    env.response.status_code = 206
+    env.response.headers["Accept-Ranges"] = "bytes"
+
+    ranges.each do |start_byte, end_byte|
+      env.response.print "--#{boundary}\r\n"
+      env.response.print "Content-Type: #{env.response.headers["Content-Type"]}\r\n"
+      env.response.print "Content-Range: bytes #{start_byte}-#{end_byte}/#{fileb}\r\n"
+      env.response.print "\r\n"
+
+      file.seek(start_byte)
+      IO.copy(file, env.response, 1_i64 + end_byte - start_byte)
+      env.response.print "\r\n"
+    end
+    env.response.print "--#{boundary}--\r\n"
   end
 end
 
+private def parse_ranges(range_header : String?, file_size : Int64) : Array({Int64, Int64})
+  return [] of {Int64, Int64} unless range_header
+
+  ranges = [] of {Int64, Int64}
+  return ranges unless range_header.starts_with?("bytes=")
+
+  range_header[6..].split(",").each do |range|
+    if match = range.match /(\d{1,})-(\d{0,})/
+      startb = match[1].to_i64 { 0_i64 }
+      endb = match[2].to_i64 { 0_i64 }
+      endb = file_size - 1 if endb == 0
+
+      if startb < endb && endb < file_size
+        ranges << {startb, endb}
+      end
+    end
+  end
+
+  ranges
+end
+
 # Set the Content-Disposition to "attachment" with the specified filename,
 # instructing the user agents to prompt to save.
 private def attachment(env : HTTP::Server::Context, filename : String? = nil, disposition : String? = nil)
@@ -244,7 +290,7 @@ end
 #
 # Disabled by default.
 def gzip(status : Bool = false)
-  add_handler HTTP::CompressHandler.new if status
+  use HTTP::CompressHandler.new if status
 end
 
 # Adds headers to `Kemal::StaticFileHandler`. This is especially useful for `CORS`.
@@ -257,6 +303,6 @@ end
 #   env.response.headers.add("Content-Size", filestat.size.to_s)
 # end
 # ```
-def static_headers(&headers : HTTP::Server::Context, String, File::Info -> Void)
+def static_headers(&headers : HTTP::Server::Context, String, File::Info ->)
   Kemal.config.static_headers = headers
 end

src/kemal/helpers/macros.cr

@@ -34,15 +34,15 @@ CONTENT_FOR_BLOCKS = Hash(String, Tuple(String, Proc(Nil))).new
 # layout, inside the <head> tag, and each view can call `content_for`
 # setting the appropriate set of tags that should be added to the layout.
 macro content_for(key, file = __FILE__)
-  CONTENT_FOR_BLOCKS[{{key}}] = Tuple.new {{file}}, ->() { {{ yield }} }
+  CONTENT_FOR_BLOCKS[{{ key }}] = Tuple.new {{ file }}, ->() { {{ yield }} }
   nil
 end
 
 # Yields content for the given key if a `content_for` block exists for that key.
 macro yield_content(key)
-  if CONTENT_FOR_BLOCKS.has_key?({{key}})
-    __caller_filename__ = CONTENT_FOR_BLOCKS[{{key}}][0]
-    %proc = CONTENT_FOR_BLOCKS[{{key}}][1]
+  if CONTENT_FOR_BLOCKS.has_key?({{ key }})
+    __caller_filename__ = CONTENT_FOR_BLOCKS[{{ key }}][0]
+    %proc = CONTENT_FOR_BLOCKS[{{ key }}][1]
 
     if __content_filename__ == __caller_filename__
       %old_content_io, content_io = content_io, IO::Memory.new
@@ -60,18 +60,45 @@ end
 # render "src/views/index.ecr", "src/views/layout.ecr"
 # ```
 macro render(filename, layout)
-  __content_filename__ = {{filename}}
+  __content_filename__ = {{ filename }}
   content_io = IO::Memory.new
-  ECR.embed {{filename}}, content_io
+  ECR.embed {{ filename }}, content_io
   content = content_io.to_s
   layout_io = IO::Memory.new
-  ECR.embed {{layout}}, layout_io
+  ECR.embed {{ layout }}, layout_io
   layout_io.to_s
 end
 
 # Render view with the given filename.
 macro render(filename)
-  ECR.render({{filename}})
+  ECR.render({{ filename }})
+end
+
+# Halts execution by closing the response. Designed for use with chained response method calls.
+#
+# ```
+# # Example: Send a JSON error and halt immediately
+# halt env.status(500).json({error: "Internal Server Error"})
+#
+# # Example: Immediately close and halt after rendering HTML
+# halt env.status(403).html("Forbidden")
+# ```
+#
+# NOTE: For most cases that require setting a specific status code and body, prefer the alternative:
+#
+# ```
+# halt env, status_code: 403, response: "Forbidden"
+# ```
+macro halt(response)
+  {% if response.is_a?(Call) && response.receiver %}
+    %env = {{ response.receiver }}
+    {{ response }}
+    %env.response.close
+    next
+  {% else %}
+    {{ response }}.response.close
+    next
+  {% end %}
 end
 
 # Halt execution with the current context.
@@ -81,9 +108,9 @@ end
 # halt env, status_code: 403, response: "Forbidden"
 # ```
 macro halt(env, status_code = 200, response = "")
-  {{env}}.response.status_code = {{status_code}}
-  {{env}}.response.print {{response}}
-  {{env}}.response.close
+  {{ env }}.response.status_code = {{ status_code }}
+  {{ env }}.response.print {{ response }}
+  {{ env }}.response.close
   next
 end
 

src/kemal/log_handler.cr

@@ -1,5 +1,6 @@
 module Kemal
   # Uses `STDOUT` by default and handles the logging of request/response process time.
+  @[Deprecated("Setup Log instead.")]
   class LogHandler < Kemal::BaseLogHandler
     def initialize(@io : IO = STDOUT)
     end

src/kemal/null_log_handler.cr

@@ -1,5 +1,6 @@
 module Kemal
   # This is here to represent the logger corresponding to Null Object Pattern.
+  @[Deprecated("Use standard library Log")]
   class NullLogHandler < Kemal::BaseLogHandler
     def call(context : HTTP::Server::Context)
       call_next(context)

src/kemal/override_method_handler.cr

@@ -4,7 +4,7 @@ module Kemal
   # This middleware is **not** in the default Kemal handlers. You need to explicitly add this to your handlers:
   #
   # ```ruby
-  # add_handler Kemal::OverrideMethodHandler
+  # use Kemal::OverrideMethodHandler::INSTANCE
   # ```
   #
   # **Important:** This middleware consumes `params.body` to read the `_method` magic parameter.
@@ -21,6 +21,7 @@ module Kemal
       if request.method == OVERRIDE_METHOD
         if context.params.body.has_key?(OVERRIDE_METHOD_PARAM_KEY) && override_method_valid?(context.params.body[OVERRIDE_METHOD_PARAM_KEY])
           request.method = context.params.body["_method"].upcase
+          context.invalidate_route_cache
         end
       end
       call_next(context)

src/kemal/param_parser.cr

@@ -6,21 +6,61 @@ module Kemal
     URL_ENCODED_FORM = "application/x-www-form-urlencoded"
     APPLICATION_JSON = "application/json"
     MULTIPART_FORM   = "multipart/form-data"
-    PARTS            = %w(url query body json files)
+    PARTS            = %w[url query body json files]
     # :nodoc:
-    alias AllParamTypes = Nil | String | Int64 | Float64 | Bool | Hash(String, JSON::Any) | Array(JSON::Any)
-    getter files
+    alias AllParamTypes = String | Int64 | Float64 | Bool | Hash(String, JSON::Any) | Array(JSON::Any)?
+    getter files, all_files
 
     def initialize(@request : HTTP::Request, @url : Hash(String, String) = {} of String => String)
       @query = HTTP::Params.new({} of String => Array(String))
       @body = HTTP::Params.new({} of String => Array(String))
       @json = {} of String => AllParamTypes
       @files = {} of String => FileUpload
+      @all_files = {} of String => Array(FileUpload)
       @url_parsed = false
       @query_parsed = false
       @body_parsed = false
       @json_parsed = false
       @files_parsed = false
+      @cached_body = nil
+    end
+
+    # Returns the raw request body, read and cached on first access.
+    # Allows multiple handlers to access the body without consuming the IO.
+    # Only caches for `application/x-www-form-urlencoded` and `application/json`.
+    def raw_body : String
+      if cached = @cached_body
+        return cached
+      end
+
+      content_type = @request.headers["Content-Type"]?
+      return @cached_body = "" if content_type.nil?
+
+      if content_type.try(&.starts_with?(URL_ENCODED_FORM)) || content_type.try(&.starts_with?(APPLICATION_JSON))
+        validate_content_length!
+        @cached_body = if body_io = @request.body
+                         read_body_with_limit(body_io)
+                       else
+                         ""
+                       end
+      else
+        @cached_body = ""
+      end
+    end
+
+    def cleanup_temporary_files
+      return if @files.empty? && @all_files.empty?
+
+      @files.each_value &.cleanup
+      @all_files.each_value do |file_uploads|
+        file_uploads.each &.cleanup
+      end
+    end
+
+    # Updates url params (e.g. after request method override). Used by Context#invalidate_route_cache.
+    def update_url_params(new_url : Hash(String, String))
+      @url = new_url
+      @url_parsed = false
     end
 
     private def unescape_url_param(value : String)
@@ -30,14 +70,14 @@ module Kemal
     end
 
     {% for method in PARTS %}
-      def {{method.id}}
+      def {{ method.id }}
         # check memoization
-        return @{{method.id}} if @{{method.id}}_parsed
+        return @{{ method.id }} if @{{ method.id }}_parsed
 
-        parse_{{method.id}}
+        parse_{{ method.id }}
         # memoize
-        @{{method.id}}_parsed = true
-        @{{method.id}}
+        @{{ method.id }}_parsed = true
+        @{{ method.id }}
       end
     {% end %}
 
@@ -46,8 +86,10 @@ module Kemal
 
       return unless content_type
 
+      validate_content_length!
+
       if content_type.try(&.starts_with?(URL_ENCODED_FORM))
-        @body = parse_part(@request.body)
+        @body = parse_part(raw_body)
         return
       end
 
@@ -67,15 +109,23 @@ module Kemal
     private def parse_files
       return if @files_parsed
 
+      validate_content_length!
+
       HTTP::FormData.parse(@request) do |upload|
         next unless upload
 
         filename = upload.filename
+        name = upload.name
 
         if !filename.nil?
-          @files[upload.name] = FileUpload.new(upload)
+          if name.ends_with?("[]")
+            @all_files[name] ||= [] of FileUpload
+            @all_files[name] << FileUpload.new(upload)
+          else
+            @files[name] = FileUpload.new(upload)
+          end
         else
-          @body.add(upload.name, upload.body.gets_to_end)
+          @body.add(name, upload.body.gets_to_end)
         end
       end
 
@@ -87,10 +137,12 @@ module Kemal
     # - If request body is a JSON `Hash` then all the params are parsed and added into `params`.
     # - If request body is a JSON `Array` it's added into `params` as `_json` and can be accessed like `params["_json"]`.
     private def parse_json
-      return unless @request.body && @request.headers["Content-Type"]?.try(&.starts_with?(APPLICATION_JSON))
+      return unless @request.headers["Content-Type"]?.try(&.starts_with?(APPLICATION_JSON))
 
-      body = @request.body.not_nil!.gets_to_end
-      case json = JSON.parse(body).raw
+      body_str = raw_body
+      return if body_str.empty?
+
+      case json = JSON.parse(body_str).raw
       when Hash
         json.each do |key, value|
           @json[key] = value.raw
@@ -103,11 +155,31 @@ module Kemal
     end
 
     private def parse_part(part : IO?)
-      HTTP::Params.parse(part ? part.gets_to_end : "")
+      return HTTP::Params.new({} of String => Array(String)) unless part
+      body_str = read_body_with_limit(part)
+      HTTP::Params.parse(body_str)
     end
 
     private def parse_part(part : String?)
       HTTP::Params.parse part.to_s
     end
+
+    private def validate_content_length!
+      return unless length_str = @request.headers["Content-Length"]?
+      return unless length = length_str.to_i?
+      return if length <= Kemal.config.max_request_body_size
+
+      raise Exceptions::PayloadTooLarge.new
+    end
+
+    private def read_body_with_limit(io : IO) : String
+      limit = Kemal.config.max_request_body_size
+      String.build do |str|
+        bytes_read = IO.copy(io, str, limit + 1)
+        if bytes_read > limit
+          raise Exceptions::PayloadTooLarge.new
+        end
+      end
+    end
   end
 end

src/kemal/path_handler.cr

@@ -0,0 +1,46 @@
+module Kemal
+  # `PathHandler` wraps a `HTTP::Handler` to only execute for specific path prefixes.
+  #
+  # ## Example
+  #
+  # ```
+  # use "/api", AuthHandler.new
+  # ```
+  #
+  # The handler will only execute for requests matching the path prefix:
+  # - `/api` matches `/api`, `/api/users`, `/api/posts/1`
+  # - `/api` does NOT match `/`, `/apiv2`, `/other`
+  class PathHandler
+    include HTTP::Handler
+
+    getter path_prefix : String
+    getter handler : HTTP::Handler
+
+    def initialize(@path_prefix : String, @handler : HTTP::Handler)
+    end
+
+    def call(context : HTTP::Server::Context)
+      if matches_prefix?(context.request.path)
+        # Set next handler for the wrapped handler
+        @handler.next = self.next
+        @handler.call(context)
+      else
+        call_next(context)
+      end
+    end
+
+    # Checks if the request path matches the handler's path prefix.
+    # - "/" or "" matches all paths
+    # - "/api" matches "/api" and "/api/*"
+    # - "/api" does NOT match "/apiv2"
+    private def matches_prefix?(path : String) : Bool
+      return true if path_prefix.in?("/", "")
+
+      # Exact match
+      return true if path == path_prefix
+
+      # Prefix match (must be followed by /)
+      path.starts_with?("#{path_prefix}/")
+    end
+  end
+end

src/kemal/request_log_handler.cr

@@ -0,0 +1,20 @@
+module Kemal
+  # :nodoc:
+  class RequestLogHandler
+    include HTTP::Handler
+
+    def call(context : HTTP::Server::Context)
+      elapsed_time = Time.measure { call_next(context) }
+      elapsed_text = elapsed_text(elapsed_time)
+      Log.info { "#{context.response.status_code} #{context.request.method} #{context.request.resource} #{elapsed_text}" }
+      context
+    end
+
+    private def elapsed_text(elapsed)
+      millis = elapsed.total_milliseconds
+      return "#{millis.round(2)}ms" if millis >= 1
+
+      "#{(millis * 1000).round(2)}µs"
+    end
+  end
+end

src/kemal/route_handler.cr

@@ -1,16 +1,122 @@
 require "radix"
 
 module Kemal
+  # Small, private LRU cache used by the router to avoid full cache clears
+  # when many distinct paths are accessed. Keeps get/put at O(1).
+  # This is intentionally minimal and file-local to avoid API surface.
+  class LRUCache(K, V)
+    # Doubly-linked list node
+    class Node(K, V)
+      property key : K
+      property value : V
+      property prev : Node(K, V)?
+      property next : Node(K, V)?
+
+      def initialize(@key : K, @value : V)
+        @prev = nil
+        @next = nil
+      end
+    end
+
+    @capacity : Int32
+    @map : Hash(K, Node(K, V))
+    @head : Node(K, V)? # most-recent
+    @tail : Node(K, V)? # least-recent
+
+    def initialize(@capacity : Int32)
+      @map = Hash(K, Node(K, V)).new
+      @head = nil
+      @tail = nil
+    end
+
+    def size : Int32
+      @map.size
+    end
+
+    def get(key : K) : V?
+      if node = @map[key]?
+        move_to_front(node)
+        return node.value
+      end
+      nil
+    end
+
+    def put(key : K, value : V) : Nil
+      if node = @map[key]?
+        node.value = value
+        move_to_front(node)
+        return
+      end
+
+      # Evict before adding to avoid unnecessary hash resize
+      evict_if_at_capacity
+
+      node = Node(K, V).new(key, value)
+      @map[key] = node
+      insert_front(node)
+    end
+
+    private def insert_front(node : Node(K, V))
+      node.prev = nil
+      node.next = @head
+      @head.try(&.prev=(node))
+      @head = node
+      @tail = node if @tail.nil?
+    end
+
+    private def move_to_front(node : Node(K, V))
+      return if node == @head
+
+      # unlink
+      prev = node.prev
+      nxt = node.next
+      prev.try(&.next=(nxt))
+      nxt.try(&.prev=(prev))
+
+      # fix tail if needed
+      if node == @tail
+        @tail = prev
+      end
+
+      insert_front(node)
+    end
+
+    private def evict_if_at_capacity
+      return if @map.size < @capacity
+
+      if lru = @tail
+        # unlink tail
+        prev = lru.prev
+        if prev
+          prev.next = nil
+          @tail = prev
+        else
+          # only one element
+          @head = nil
+          @tail = nil
+        end
+        @map.delete(lru.key)
+      end
+    end
+  end
+
   class RouteHandler
     include HTTP::Handler
 
-    INSTANCE            = new
-    CACHED_ROUTES_LIMIT = 1024
-    property routes, cached_routes
+    INSTANCE = new
+    property routes
+
+    getter cached_routes
+
+    # Setter is synchronized for thread-safety when specs reset the cache.
+    def cached_routes=(cache : LRUCache(String, Radix::Result(Route)))
+      @cache_mutex.synchronize { @cached_routes = cache }
+    end
 
     def initialize
       @routes = Radix::Tree(Route).new
-      @cached_routes = Hash(String, Radix::Result(Route)).new
+      @cached_routes = LRUCache(String, Radix::Result(Route)).new(Kemal.config.max_route_cache_size)
+      @cache_mutex = Mutex.new
     end
 
     def call(context : HTTP::Server::Context)
@@ -23,23 +129,29 @@ module Kemal
     end
 
     # Looks up the route from the Radix::Tree for the first time and caches to improve performance.
+    # Cache access is synchronized so multiple fibers can call this concurrently.
     def lookup_route(verb : String, path : String)
       lookup_path = radix_path(verb, path)
 
-      if cached_route = @cached_routes[lookup_path]?
-        return cached_route
+      @cache_mutex.synchronize do
+        if cached_route = @cached_routes.get(lookup_path)
+          return cached_route
+        end
       end
 
       route = @routes.find(lookup_path)
 
       if verb == "HEAD" && !route.found?
         # On HEAD requests, implicitly fallback to running the GET handler.
-        route = @routes.find(radix_path("GET", path))
-      end
-
-      if route.found?
-        @cached_routes.clear if @cached_routes.size == CACHED_ROUTES_LIMIT
-        @cached_routes[lookup_path] = route
+        get_lookup_path = radix_path("GET", path)
+        get_route = @routes.find(get_lookup_path)
+        # Cache the HEAD->GET fallback result using the original HEAD lookup_path
+        if get_route.found?
+          @cache_mutex.synchronize { @cached_routes.put(lookup_path, get_route) }
+        end
+        route = get_route
+      elsif route.found?
+        @cache_mutex.synchronize { @cached_routes.put(lookup_path, route) }
       end
 
       route
@@ -56,11 +168,14 @@ module Kemal
       end
 
       context.response.print(content)
+
       context
+    ensure
+      context.params.cleanup_temporary_files
     end
 
     private def radix_path(method, path)
-      '/' + method + path
+      "/#{method}#{path}"
     end
 
     private def add_to_radix_tree(method, path, route)

src/kemal/router.cr

@@ -0,0 +1,304 @@
+module Kemal
+  # Router provides modular routing capabilities for Kemal applications.
+  #
+  # It allows grouping routes under a common prefix and applying filters
+  # to specific route groups. Routers can be nested using `namespace`.
+  #
+  # ## Example
+  #
+  # ```
+  # api = Kemal::Router.new
+  #
+  # api.before do |env|
+  #   env.response.content_type = "application/json"
+  # end
+  #
+  # api.get "/users" do |env|
+  #   User.all.to_json
+  # end
+  #
+  # api.namespace "/admin" do
+  #   get "/dashboard" do |env|
+  #     {status: "ok"}.to_json
+  #   end
+  # end
+  #
+  # mount "/api/v1", api
+  # ```
+  class Router
+    alias RouteHandler = HTTP::Server::Context -> String
+    alias FilterHandler = HTTP::Server::Context -> String
+    alias WSHandler = HTTP::WebSocket, HTTP::Server::Context ->
+
+    # Stored route definition
+    private record RouteDefinition,
+      method : String,
+      path : String,
+      handler : RouteHandler
+
+    # Stored filter definition
+    private record FilterDefinition,
+      type : Symbol,
+      method : String,
+      path : String,
+      handler : FilterHandler
+
+    # Stored websocket definition
+    private record WSDefinition,
+      path : String,
+      handler : WSHandler
+
+    # Stored sub-router
+    private record SubRouter,
+      path : String,
+      router : Router
+
+    getter prefix : String
+
+    @routes : Array(RouteDefinition)
+    @filters : Array(FilterDefinition)
+    @websockets : Array(WSDefinition)
+    @sub_routers : Array(SubRouter)
+
+    def initialize(@prefix : String = "")
+      @routes = [] of RouteDefinition
+      @filters = [] of FilterDefinition
+      @websockets = [] of WSDefinition
+      @sub_routers = [] of SubRouter
+    end
+
+    # HTTP method helpers
+    {% for method in HTTP_METHODS %}
+      # Defines a {{ method.id.upcase }} route.
+      #
+      # ```
+      # router.{{ method.id }} "/path" do |env|
+      #   "response"
+      # end
+      # ```
+      def {{ method.id }}(path : String, &block : HTTP::Server::Context -> _)
+        add_route({{ method.upcase }}, path, &block)
+      end
+    {% end %}
+
+    # Defines a WebSocket route.
+    #
+    # ```
+    # router.ws "/chat" do |socket, env|
+    #   socket.on_message do |msg|
+    #     socket.send "Echo: #{msg}"
+    #   end
+    # end
+    # ```
+    def ws(path : String, &block : HTTP::WebSocket, HTTP::Server::Context ->)
+      @websockets << WSDefinition.new(path: path, handler: block)
+    end
+
+    # Defines a before filter for all HTTP methods.
+    #
+    # ```
+    # router.before do |env|
+    #   env.response.content_type = "application/json"
+    # end
+    # ```
+    def before(path : String = "*", &block : HTTP::Server::Context -> _)
+      add_filter(:before, "ALL", path, &block)
+    end
+
+    # Defines an after filter for all HTTP methods.
+    #
+    # ```
+    # router.after do |env|
+    #   puts "Request completed"
+    # end
+    # ```
+    def after(path : String = "*", &block : HTTP::Server::Context -> _)
+      add_filter(:after, "ALL", path, &block)
+    end
+
+    # Method-specific before/after filters
+    {% for method in FILTER_METHODS %}
+      # Defines a before filter for {{ method.id.upcase }} requests.
+      def before_{{ method.id }}(path : String = "*", &block : HTTP::Server::Context -> _)
+        add_filter(:before, {{ method.upcase }}, path, &block)
+      end
+
+      # Defines an after filter for {{ method.id.upcase }} requests.
+      def after_{{ method.id }}(path : String = "*", &block : HTTP::Server::Context -> _)
+        add_filter(:after, {{ method.upcase }}, path, &block)
+      end
+    {% end %}
+
+    # Creates a nested namespace/group with the given *path* prefix.
+    #
+    # NOTE: The path must start with a `/`.
+    #
+    # All routes defined inside the block will be prefixed with the given path.
+    #
+    # ```
+    # router.namespace "/users" do
+    #   get "/" do |env|
+    #     User.all.to_json
+    #   end
+    #
+    #   get "/:id" do |env|
+    #     User.find(env.params.url["id"]).to_json
+    #   end
+    # end
+    # ```
+    def namespace(path : String, &)
+      sub_router = Router.new
+      with sub_router yield
+      @sub_routers << SubRouter.new(path: path, router: sub_router)
+    end
+
+    # Mounts another router at the given *path* prefix.
+    #
+    # NOTE: The path must start with a `/`.
+    #
+    # ```
+    # users_router = Kemal::Router.new
+    # users_router.get "/" { |env| "users" }
+    #
+    # api = Kemal::Router.new
+    # api.mount "/users", users_router
+    #
+    # mount "/api", api
+    # # Result: GET /api/users
+    # ```
+    def mount(path : String, router : Router)
+      @sub_routers << SubRouter.new(path: path, router: router)
+    end
+
+    # Mounts another router without additional prefix.
+    def mount(router : Router)
+      mount("", router)
+    end
+
+    # Registers all routes, filters, and websockets with Kemal's handlers.
+    # This is called automatically when using `mount` from DSL.
+    #
+    # :nodoc:
+    def register_routes(base_prefix : String = "")
+      full_prefix = join_paths(base_prefix, @prefix)
+
+      # Collect all route paths for filter registration
+      route_paths = collect_all_route_paths(full_prefix)
+
+      # Register filters for each route path
+      register_filters(full_prefix, route_paths)
+
+      # Register routes
+      @routes.each do |route|
+        full_path = join_paths(full_prefix, route.path)
+        validate_path!(route.method.downcase, full_path)
+        Kemal::RouteHandler::INSTANCE.add_route(route.method, full_path) do |env|
+          route.handler.call(env)
+        end
+      end
+
+      # Register websockets
+      @websockets.each do |ws_def|
+        full_path = join_paths(full_prefix, ws_def.path)
+        validate_path!("ws", full_path)
+        Kemal::WebSocketHandler::INSTANCE.add_route(full_path, &ws_def.handler)
+      end
+
+      # Register sub-routers recursively
+      @sub_routers.each do |sub|
+        sub_prefix = join_paths(full_prefix, sub.path)
+        sub.router.register_routes(sub_prefix)
+      end
+    end
+
+    # Collect all route paths including sub-routers
+    protected def collect_all_route_paths(full_prefix : String) : Array(Tuple(String, String))
+      paths = [] of Tuple(String, String)
+
+      # This router's routes
+      @routes.each do |route|
+        full_path = join_paths(full_prefix, route.path)
+        paths << {route.method, full_path}
+      end
+
+      # Sub-router routes
+      @sub_routers.each do |sub|
+        sub_prefix = join_paths(full_prefix, sub.path)
+        paths.concat(sub.router.collect_all_route_paths(sub_prefix))
+      end
+
+      paths
+    end
+
+    # Register filters for specific route paths
+    private def register_filters(full_prefix : String, route_paths : Array(Tuple(String, String)))
+      return if @filters.empty?
+
+      # Ensure FilterHandler is registered with Kemal (may have been cleared between tests)
+      unless Kemal::Config::FILTER_HANDLERS.includes?(Kemal::FilterHandler::INSTANCE)
+        Kemal.config.add_filter_handler(Kemal::FilterHandler::INSTANCE)
+      end
+
+      @filters.each do |filter|
+        # Determine which paths this filter applies to
+        applicable_paths = if filter.path == "*"
+                             # Apply to all routes in this router
+                             route_paths
+                           else
+                             # Apply to specific path
+                             filter_full_path = join_paths(full_prefix, filter.path)
+                             route_paths.select { |_, path| path == filter_full_path || path.starts_with?(filter_full_path + "/") }
+                           end
+
+        applicable_paths.each do |route_method, route_path|
+          # Check if filter method matches route method
+          next unless filter.method.in?("ALL", route_method)
+
+          # Use filter's method (ALL or specific) when registering
+          register_method = filter.method
+
+          case filter.type
+          when :before
+            Kemal::FilterHandler::INSTANCE.before(register_method, route_path) do |env|
+              filter.handler.call(env)
+            end
+          when :after
+            Kemal::FilterHandler::INSTANCE.after(register_method, route_path) do |env|
+              filter.handler.call(env)
+            end
+          end
+        end
+      end
+    end
+
+    private def add_route(method : String, path : String, &block : HTTP::Server::Context -> _)
+      handler = ->(ctx : HTTP::Server::Context) do
+        result = block.call(ctx)
+        result.is_a?(String) ? result : ""
+      end
+      @routes << RouteDefinition.new(method: method, path: path, handler: handler)
+    end
+
+    private def add_filter(type : Symbol, method : String, path : String, &block : HTTP::Server::Context -> _)
+      handler = ->(ctx : HTTP::Server::Context) do
+        result = block.call(ctx)
+        result.is_a?(String) ? result : ""
+      end
+      @filters << FilterDefinition.new(type: type, method: method, path: path, handler: handler)
+    end
+
+    private def join_paths(a : String, b : String) : String
+      a = a.chomp('/')
+      b = b.lchop('/') if b.starts_with?('/')
+      return "/#{b}" if a.empty?
+      return a if b.empty?
+      "#{a}/#{b}"
+    end
+
+    private def validate_path!(method : String, path : String)
+      unless Utils.path_starts_with_slash?(path)
+        raise Exceptions::InvalidPathStartException.new(method, path)
+      end
+    end
+  end
+end

src/kemal/static_file_handler.cr

@@ -1,53 +1,104 @@
 module Kemal
   class StaticFileHandler < HTTP::StaticFileHandler
-    # ameba:disable Metrics/CyclomaticComplexity
-    def call(context : HTTP::Server::Context)
-      return call_next(context) if context.request.path.not_nil! == "/"
-
-      case context.request.method
-      when "GET", "HEAD"
-      else
-        if @fallthrough
-          call_next(context)
-        else
-          context.response.status_code = 405
-          context.response.headers.add("Allow", "GET, HEAD")
+    {% if compare_versions(Crystal::VERSION, "1.17.0") >= 0 %}
+      private def directory_index(context : HTTP::Server::Context, request_path : Path, file_path : Path)
+        config = Kemal.config.serve_static
+        unless config.is_a?(Hash)
+          return call_next(context)
+        end
+
+        index_path = file_path / "index.html"
+        if config.fetch("dir_index", false) && (index_info = File.info?(index_path))
+          last_modified = index_info.modification_time
+          add_cache_headers(context.response.headers, last_modified)
+
+          if cache_request?(context, last_modified)
+            context.response.status = :not_modified
+            return
+          end
+
+          send_file(context, index_path.to_s)
+        elsif config.fetch("dir_listing", false)
+          context.response.content_type = "text/html; charset=utf-8"
+          directory_listing(context.response, request_path, file_path)
+        else
+          call_next(context)
         end
-        return
       end
 
-      config = Kemal.config.serve_static
-      original_path = context.request.path.not_nil!
-      request_path = URI.decode(original_path)
-
-      # File path cannot contains '\0' (NUL) because all filesystem I know
-      # don't accept '\0' character as file name.
-      if request_path.includes? '\0'
-        context.response.status_code = 400
-        return
+      # NOTE: This override opts out of some behaviour from HTTP::StaticFileHandler,
+      # such as serving content ranges.
+      private def serve_file(context : HTTP::Server::Context, file_info, file_path : Path, original_file_path : Path, last_modified : Time)
+        send_file(context, file_path.to_s)
       end
+    {% else %}
+      def call(context : HTTP::Server::Context)
+        return call_next(context) if context.request.path.not_nil! == "/"
 
-      expanded_path = request_path
-      is_dir_path = if original_path.ends_with?('/') && !expanded_path.ends_with? '/'
-                      expanded_path = expanded_path + '/'
-                      true
-                    else
-                      expanded_path.ends_with? '/'
-                    end
+        case context.request.method
+        when "GET", "HEAD"
+        else
+          if @fallthrough
+            call_next(context)
+          else
+            context.response.status_code = 405
+            context.response.headers.add("Allow", "GET, HEAD")
+          end
+          return
+        end
 
-      file_path = File.join(@public_dir, expanded_path)
-      is_dir = Dir.exists?(file_path)
+        original_path = context.request.path.not_nil!
+        is_dir_path = original_path.ends_with?("/")
+        request_path = URI.decode(original_path)
 
-      if request_path != expanded_path
-        redirect_to context, expanded_path
-      elsif is_dir && !is_dir_path
-        redirect_to context, expanded_path + '/'
-      end
+        # File path cannot contains '\0' (NUL) because all filesystem I know
+        # don't accept '\0' character as file name.
+        if request_path.includes? '\0'
+          context.response.respond_with_status(:bad_request)
+          return
+        end
 
-      if is_dir
-        if config.is_a?(Hash) && config.fetch("dir_index", false) && File.exists?(File.join(file_path, "index.html"))
-          file_path = File.join(@public_dir, expanded_path, "index.html")
+        request_path = Path.posix(request_path)
+        expanded_path = request_path.expand("/")
 
+        file_path = @public_dir.join(expanded_path.to_kind(Path::Kind.native))
+        file_info = File.info? file_path
+        is_dir = @directory_listing && file_info && file_info.directory?
+        is_file = file_info && file_info.file?
+
+        if request_path != expanded_path || is_dir && !is_dir_path
+          redirect_path = expanded_path
+          if is_dir && !is_dir_path
+            # Append / to path if missing
+            redirect_path = expanded_path.join("")
+          end
+          redirect_to context, redirect_path
+          return
+        end
+
+        return call_next(context) unless file_info
+
+        if is_dir
+          config = Kemal.config.serve_static
+
+          if config.is_a?(Hash) && config.fetch("dir_index", false) && File.exists?(File.join(file_path, "index.html"))
+            file_path = File.join(@public_dir, expanded_path, "index.html")
+
+            last_modified = modification_time(file_path)
+            add_cache_headers(context.response.headers, last_modified)
+
+            if cache_request?(context, last_modified)
+              context.response.status_code = 304
+              return
+            end
+            send_file(context, file_path)
+          elsif config.is_a?(Hash) && config.fetch("dir_listing", false)
+            context.response.content_type = "text/html; charset=utf-8"
+            directory_listing(context.response, request_path, file_path)
+          else
+            call_next(context)
+          end
+        elsif is_file
           last_modified = modification_time(file_path)
           add_cache_headers(context.response.headers, last_modified)
 
@@ -55,29 +106,15 @@ module Kemal
             context.response.status_code = 304
             return
           end
-          send_file(context, file_path)
-        elsif config.is_a?(Hash) && config.fetch("dir_listing", false)
-          context.response.content_type = "text/html; charset=utf-8"
-          directory_listing(context.response, request_path, file_path)
-        else
+          send_file(context, file_path.to_s)
+        else # Not a normal file (FIFO/device/socket)
           call_next(context)
         end
-      elsif File.exists?(file_path)
-        last_modified = modification_time(file_path)
-        add_cache_headers(context.response.headers, last_modified)
-
-        if cache_request?(context, last_modified)
-          context.response.status_code = 304
-          return
-        end
-        send_file(context, file_path)
-      else
-        call_next(context)
       end
-    end
 
-    private def modification_time(file_path)
-      File.info(file_path).modification_time
-    end
+      private def modification_time(file_path)
+        File.info(file_path).modification_time
+      end
+    {% end %}
   end
 end

src/kemal/websocket.cr

@@ -6,7 +6,7 @@ module Kemal
   class WebSocket < HTTP::WebSocketHandler
     getter proc
 
-    def initialize(@path : String, &@proc : HTTP::WebSocket, HTTP::Server::Context -> Void)
+    def initialize(@path : String, &@proc : HTTP::WebSocket, HTTP::Server::Context ->)
     end
 
     def error(code : Int16, message : String)

src/kemal/websocket_handler.cr

@@ -38,7 +38,7 @@ module Kemal
       @routes.find "/ws" + path
     end
 
-    def add_route(path : String, &handler : HTTP::WebSocket, HTTP::Server::Context -> Void)
+    def add_route(path : String, &handler : HTTP::WebSocket, HTTP::Server::Context ->)
       add_to_radix_tree path, WebSocket.new(path, &handler)
     end