diff --git a/src/custom.zig b/src/custom.zig
index a91bdd2..f346fa0 100644
--- a/src/custom.zig
+++ b/src/custom.zig
@@ -120,8 +120,9 @@ pub const Write = struct {
         allocator: *std.mem.Allocator,
         params: *plugins.ParamMap,
     ) Write {
+        const data = params.get("data").?;
         return Write{
-            .data = params.get("data").?.value,
+            .data = data.value,
         };
     }
 
@@ -139,10 +140,10 @@ pub const Embed = struct {
     sndfile: *c.SNDFILE = undefined,
     buf: []f32 = undefined,
 
-    pub fn init(allocator: *std.mem.Allocator, params: *plugins.ParmaMap) @This() {
+    pub fn init(allocator: *std.mem.Allocator, filepath: []const u8) @This() {
         return Embed{
             .allocator = allocator,
-            .filepath = params.get("path").?.value,
+            .filepath = filepath,
         };
     }
 
diff --git a/src/image.zig b/src/image.zig
index d677afa..7f8deb4 100644
--- a/src/image.zig
+++ b/src/image.zig
@@ -422,7 +422,8 @@ pub const Image = struct {
         self: *Image,
         comptime Plugin: type,
         position: plugins.Position,
-        extra: *ParamMap,
+        comptime ExtraType: type,
+        extra: ExtraType,
     ) !void {
         var plugin_opt: ?Plugin = Plugin.init(self.allocator, extra);
         if (plugin_opt == null) {
diff --git a/src/lang.zig b/src/lang.zig
index cc8d58a..03a6c52 100644
--- a/src/lang.zig
+++ b/src/lang.zig
@@ -1,7 +1,6 @@
 const std = @import("std");
 
 const plugin = @import("plugin.zig");
-const custom = @import("custom.zig");
 
 pub const ParseError = error{
     OutOfMemory,
@@ -13,8 +12,6 @@ pub const CommandType = enum {
     /// "LV2 Commands" are commands that receive split, index, and then receive
     /// any f64 arguments.
     lv2_command,
-
-    custom_command,
 };
 
 fn LV2Command(
@@ -35,19 +32,19 @@ fn LV2Command(
 }
 
 fn CustomCommand(
-    comptime tag: Command.Tag,
-    comptime Plugin: type,
-    comptime PluginParameters: type,
+    comptime tag: Command.tag,
+    comptime plugin: type,
+    comptime parameters: type,
 ) type {
     return struct {
         pub const base_tag = tag;
-        pub const command_type = CommandType.custom_command;
-        pub const plugin_type = Plugin;
+        pub const command_type = CommandType.plugin_command;
+        pub const plugin_type = plugin;
 
         base: Command,
         split: usize,
         index: usize,
-        parameters: PluginParameters,
+        parameters: LV2Parameters,
     };
 }
 
@@ -191,9 +188,13 @@ pub const Command = struct {
         data: f32,
     });
 
-    pub const Embed = CustomCommand(Tag.write, custom.Embed, struct {
+    pub const Embed = struct {
+        pub const base_tag = Tag.embed;
+        base: Command,
+        split: usize,
+        index: usize,
         path: []const u8,
-    });
+    };
 
     pub const Rotate = struct {
         pub const base_tag = Tag.rotate;
@@ -520,7 +521,7 @@ pub const Lang = struct {
         // Based on the command struct fields, we can parse the arguments.
         var cmd = try self.allocator.create(command_struct);
         const is_lv2_command = switch (command_struct.base_tag) {
-            .noop, .load, .quicksave, .runqs, .rotate => false,
+            .noop, .load, .quicksave, .runqs => false,
             else => command_struct.command_type == .lv2_command,
         };
 
diff --git a/src/runner.zig b/src/runner.zig
index a1bed65..e65bac0 100644
--- a/src/runner.zig
+++ b/src/runner.zig
@@ -190,6 +190,26 @@ pub const Runner = struct {
         _ = try proc.spawnAndWait();
     }
 
+    fn noiseCmd(self: *Runner, pos: Position, map: *ParamMap) !void {
+        var image = try self.getImage();
+        try image.runCustomPlugin(custom.RandomNoise, pos, *ParamMap, map);
+    }
+
+    fn wildNoiseCmd(self: *Runner, pos: Position, map: *ParamMap) !void {
+        var image = try self.getImage();
+        try image.runCustomPlugin(custom.WildNoise, pos, *ParamMap, map);
+    }
+
+    fn writeCmd(self: *Runner, pos: Position, map: *ParamMap) !void {
+        var image = try self.getImage();
+        try image.runCustomPlugin(custom.Write, pos, *ParamMap, map);
+    }
+
+    fn embedCmd(self: *Runner, pos: Position, path: []const u8) !void {
+        var image = try self.getImage();
+        try image.runCustomPlugin(custom.Embed, pos, []const u8, path);
+    }
+
     fn rotateCmd(
         self: *Runner,
         deg: f32,
@@ -224,26 +244,6 @@ pub const Runner = struct {
         try image.runPlugin(typ.lv2_url, pos, params);
     }
 
-    fn executePlugin(self: *@This(), command: var) !void {
-        const pos = plugin.Position{
-            .split = command.split,
-            .index = command.index,
-        };
-
-        var params = ParamMap.init(self.allocator);
-        defer params.deinit();
-
-        inline for (@typeInfo(@TypeOf(command.parameters)).Struct.fields) |cmd_field| {
-            try params.put(
-                cmd_field.name,
-                @field(command.parameters, cmd_field.name),
-            );
-        }
-
-        var image = try self.getImage();
-        try image.runCustomPlugin(typ.plugin_type, pos, map);
-    }
-
     fn newRunCommandSingle(
         self: *@This(),
         cmd: lang.Command,
@@ -261,7 +261,6 @@ pub const Runner = struct {
             const ctype = typ.command_type;
             switch (ctype) {
                 .lv2_command => try self.executeLV2Command(command.*),
-                .plugin_command => try self.executePlugin(command.*),
                 else => @panic("TODO support command type"),
             }
         }
@@ -306,8 +305,6 @@ pub const Runner = struct {
             .saturator => try self.newRunCommandSingle(cmd, .saturator),
             .vintagedelay => try self.newRunCommandSingle(cmd, .vintagedelay),
 
-            .noise, .wildnoise, .write, .embed => |tag| try self.newRunCommandSingle(cmd, tag),
-
             else => {
                 std.debug.warn("TODO support {}\n", .{@tagName(cmd.tag)});
                 @panic("TODO support tag");