diff --git a/Cargo.toml b/Cargo.toml
index eb5770e..1001ccb 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -18,7 +18,8 @@ path = "src/cli/main.rs"
 [dependencies]
 anyhow = "1.0.98"
 clap = { version = "4.5.38", features = ["derive"] }
-fasteval = "0.2.4"
+derive_builder = "0.20.2"
+fasteval = { git = "https://github.com/brevalferrari/fasteval" }
 flacenc = "0.4.0"
 hound = "3.5.1"
 mp3lame-encoder = { version = "0.2.1", features = ["std"] }
diff --git a/src/compiler.rs b/src/compiler.rs
new file mode 100644
index 0000000..046f42e
--- /dev/null
+++ b/src/compiler.rs
@@ -0,0 +1,50 @@
+use std::collections::HashMap;
+
+use fasteval::Instruction;
+
+pub type TokenVec = Vec<Box<dyn Token>>;
+
+pub trait Token {
+    fn apply(&self, context: Context) -> Context;
+}
+
+#[cfg_attr(debug_assertions, derive(Default))]
+#[derive(Clone, Copy)]
+pub struct Silence;
+
+#[cfg_attr(debug_assertions, derive(Default))]
+#[derive(Clone, Copy)]
+pub struct Marker;
+
+#[cfg_attr(debug_assertions, derive(Default))]
+#[derive(Clone, Copy)]
+pub struct Note(pub u8);
+
+#[cfg_attr(debug_assertions, derive(Default))]
+#[derive(Clone)]
+pub struct VariableChange(pub char, pub Instruction);
+
+#[cfg_attr(debug_assertions, derive(Default))]
+pub struct Loop(pub usize, pub TokenVec);
+
+#[cfg_attr(debug_assertions, derive(Default))]
+pub struct Tuplet(pub TokenVec);
+
+#[cfg_attr(debug_assertions, derive(Default))]
+pub struct Slope(pub VariableChange, pub TokenVec);
+
+pub struct Context {
+    pub result: Vec<f64>,
+    pub variables: HashMap<char, f64>,
+    pub instrument: Instruction,
+    pub slopes: HashMap<char, Instruction>,
+}
+
+impl Context {
+    pub fn current_length(&self) -> f64 {
+        todo!()
+    }
+    pub fn render(&self, n: Option<u8>) -> Vec<f64> {
+        todo!()
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index ae73c3e..b771520 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1 +1,2 @@
-pub struct Test;
+pub mod compiler;
+pub mod parser;
diff --git a/src/parser.rs b/src/parser.rs
new file mode 100644
index 0000000..98ac45e
--- /dev/null
+++ b/src/parser.rs
@@ -0,0 +1,55 @@
+use std::collections::HashMap;
+
+use derive_builder::Builder;
+use nom::{Compare, Input, combinator::success, error::Error};
+use nom_locate::LocatedSpan;
+
+use crate::compiler::{Marker, Note, Silence, Token, VariableChange};
+
+pub trait TokenParser<I, O>:
+    nom::Parser<LocatedSpan<I>, Output = O, Error = Error<LocatedSpan<I>>>
+{
+}
+
+impl<I, T, O> TokenParser<I, O> for T where
+    T: nom::Parser<LocatedSpan<I>, Output = O, Error = Error<LocatedSpan<I>>>
+{
+}
+
+pub struct ParserParametters<'n, 's, 'v, I: Input + Clone + Compare<I>, C: Into<char>> {
+    pub notes: &'n [I],
+    pub slopes: &'s HashMap<I, VariableChange>,
+    pub variables: &'v [C],
+}
+
+#[derive(Builder)]
+pub struct Parser<'i, 'n, 's, 'v, I: Input + Clone + Compare<I>, C: Into<char>> {
+    input: &'i I,
+    notes: &'n [I],
+    slopes: &'s HashMap<I, VariableChange>,
+    variables: &'v [C],
+}
+
+impl<'i, 'n, 's, 'v, I: Input + Clone + Compare<I>, C: Into<char>> Parser<'i, 'n, 's, 'v, I, C> {
+    pub fn parse_all() -> Result<Vec<Box<dyn Token>>, Error<nom_locate::LocatedSpan<&'i I>>> {
+        todo!()
+    }
+}
+
+impl Silence {
+    fn parser<I: Input>() -> impl TokenParser<I, Self> {
+        success(Default::default())
+    }
+}
+
+impl Marker {
+    fn parser<I: Input>() -> impl TokenParser<I, Self> {
+        success(Default::default())
+    }
+}
+
+impl Note {
+    fn parser<I: Input>() -> impl TokenParser<I, Self> {
+        success(Default::default())
+    }
+}