diff --git a/src/alejandra_engine/src/lib.rs b/src/alejandra_engine/src/lib.rs
index 2ba07fe..b750265 100644
--- a/src/alejandra_engine/src/lib.rs
+++ b/src/alejandra_engine/src/lib.rs
@@ -2,6 +2,7 @@ pub mod builder;
 pub mod children;
 pub mod config;
 pub mod format;
+pub mod parsers;
 pub mod position;
 pub mod rules;
 pub mod utils;
diff --git a/src/alejandra_engine/src/parsers/mod.rs b/src/alejandra_engine/src/parsers/mod.rs
new file mode 100644
index 0000000..def5479
--- /dev/null
+++ b/src/alejandra_engine/src/parsers/mod.rs
@@ -0,0 +1 @@
+pub mod pattern;
diff --git a/src/alejandra_engine/src/parsers/pattern.rs b/src/alejandra_engine/src/parsers/pattern.rs
new file mode 100644
index 0000000..c188b85
--- /dev/null
+++ b/src/alejandra_engine/src/parsers/pattern.rs
@@ -0,0 +1,185 @@
+use std::collections::LinkedList;
+
+#[derive(Debug)]
+pub struct Argument {
+    pub comments_before: LinkedList<String>,
+    pub item:            Option<rnix::SyntaxElement>,
+    pub comment_after:   Option<String>,
+}
+
+impl Default for Argument {
+    fn default() -> Argument {
+        Argument {
+            comments_before: LinkedList::new(),
+            item:            None,
+            comment_after:   None,
+        }
+    }
+}
+
+#[derive(Debug)]
+pub struct Pattern {
+    pub initial_at:                    Option<rnix::SyntaxElement>,
+    pub comments_after_initial_at:     LinkedList<String>,
+    pub arguments:                     LinkedList<Argument>,
+    pub comments_before_curly_b_close: LinkedList<String>,
+    pub comments_before_end_at:        LinkedList<String>,
+    pub end_at:                        Option<rnix::SyntaxElement>,
+}
+
+impl Default for Pattern {
+    fn default() -> Pattern {
+        Pattern {
+            initial_at:                    None,
+            comments_after_initial_at:     LinkedList::new(),
+            arguments:                     LinkedList::new(),
+            comments_before_curly_b_close: LinkedList::new(),
+            comments_before_end_at:        LinkedList::new(),
+            end_at:                        None,
+        }
+    }
+}
+
+pub fn parse(
+    build_ctx: &crate::builder::BuildCtx,
+    node: &rnix::SyntaxNode,
+) -> Pattern {
+    let mut pattern = Pattern::default();
+
+    let mut children = crate::children::Children::new_with_configuration(
+        build_ctx, node, true,
+    );
+
+    // x @
+    let child = children.peek_next().unwrap();
+    if let rnix::SyntaxKind::NODE_PAT_BIND = child.element.kind() {
+        pattern.initial_at = Some(child.element);
+        children.move_next();
+    }
+
+    // /**/
+    children.drain_comments_and_newlines(|element| match element {
+        crate::children::DrainCommentOrNewline::Comment(text) => {
+            pattern.comments_after_initial_at.push_back(text);
+        }
+        crate::children::DrainCommentOrNewline::Newline(_) => {}
+    });
+
+    // {
+    children.move_next();
+
+    // arguments
+    loop {
+        let mut argument = Argument::default();
+
+        // Before an item we can have: comma, comments, whitespace
+        loop {
+            let child = children.peek_next().unwrap();
+            // eprintln!("before item {:?}", child.element.kind());
+
+            match child.element.kind() {
+                rnix::SyntaxKind::NODE_PAT_ENTRY
+                | rnix::SyntaxKind::TOKEN_CURLY_B_CLOSE
+                | rnix::SyntaxKind::TOKEN_ELLIPSIS => {
+                    break;
+                }
+                rnix::SyntaxKind::TOKEN_COMMA => {
+                    children.move_next();
+                }
+                rnix::SyntaxKind::TOKEN_COMMENT => {
+                    let content =
+                        child.element.into_token().unwrap().to_string();
+
+                    argument.comments_before.push_back(content);
+                    children.move_next();
+                }
+                rnix::SyntaxKind::TOKEN_WHITESPACE => {
+                    children.move_next();
+                }
+                _ => {}
+            }
+        }
+
+        // item
+        let child = children.peek_next().unwrap();
+        // eprintln!("item {:?}", child.element.kind());
+        match child.element.kind() {
+            rnix::SyntaxKind::TOKEN_CURLY_B_CLOSE => {
+                pattern.comments_before_curly_b_close =
+                    argument.comments_before;
+                break;
+            }
+            rnix::SyntaxKind::TOKEN_ELLIPSIS
+            | rnix::SyntaxKind::NODE_PAT_ENTRY => {
+                argument.item = Some(child.element);
+                children.move_next();
+            }
+            _ => {}
+        }
+
+        // After an item we can have: comma, comments, whitespace
+        loop {
+            let child = children.peek_next().unwrap();
+            // eprintln!("after item {:?}", child.element.kind());
+
+            match child.element.kind() {
+                rnix::SyntaxKind::NODE_PAT_ENTRY
+                | rnix::SyntaxKind::TOKEN_ELLIPSIS
+                | rnix::SyntaxKind::TOKEN_CURLY_B_CLOSE => {
+                    break;
+                }
+                rnix::SyntaxKind::TOKEN_COMMA => {
+                    children.move_next();
+                }
+                rnix::SyntaxKind::TOKEN_COMMENT => {
+                    let content =
+                        child.element.into_token().unwrap().to_string();
+
+                    children.move_next();
+                    argument.comment_after = Some(content);
+                    break;
+                }
+                rnix::SyntaxKind::TOKEN_WHITESPACE => {
+                    let content =
+                        child.element.into_token().unwrap().to_string();
+
+                    children.move_next();
+                    if crate::utils::count_newlines(&content) > 0 {
+                        break;
+                    }
+                }
+                _ => {}
+            }
+        }
+
+        pattern.arguments.push_back(argument);
+    }
+
+    // /**/
+    children.drain_comments_and_newlines(|element| match element {
+        crate::children::DrainCommentOrNewline::Comment(text) => {
+            pattern.comments_before_curly_b_close.push_back(text);
+        }
+        crate::children::DrainCommentOrNewline::Newline(_) => {}
+    });
+
+    // }
+    children.move_next();
+
+    // /**/
+    children.drain_comments_and_newlines(|element| match element {
+        crate::children::DrainCommentOrNewline::Comment(text) => {
+            pattern.comments_before_end_at.push_back(text);
+        }
+        crate::children::DrainCommentOrNewline::Newline(_) => {}
+    });
+
+    // @ x
+    if let Some(child) = children.peek_next() {
+        if let rnix::SyntaxKind::NODE_PAT_BIND = child.element.kind() {
+            pattern.end_at = Some(child.element);
+        }
+    }
+
+    pattern
+}
diff --git a/src/alejandra_engine/src/rules/pattern.rs b/src/alejandra_engine/src/rules/pattern.rs
index 634d841..7b76bd1 100644
--- a/src/alejandra_engine/src/rules/pattern.rs
+++ b/src/alejandra_engine/src/rules/pattern.rs
@@ -1,196 +1,10 @@
-use std::collections::LinkedList;
-
-#[derive(Debug)]
-struct Argument {
-    comments_before: LinkedList<String>,
-    item:            Option<rnix::SyntaxElement>,
-    comment_after:   Option<String>,
-}
-
-impl Default for Argument {
-    fn default() -> Argument {
-        Argument {
-            comments_before: LinkedList::new(),
-            item:            None,
-            comment_after:   None,
-        }
-    }
-}
-
-#[derive(Debug)]
-struct Pattern {
-    initial_at:                    Option<rnix::SyntaxElement>,
-    comments_after_initial_at:     LinkedList<String>,
-    arguments:                     LinkedList<Argument>,
-    comments_before_curly_b_close: LinkedList<String>,
-    comments_before_end_at:        LinkedList<String>,
-    end_at:                        Option<rnix::SyntaxElement>,
-}
-
-impl Default for Pattern {
-    fn default() -> Pattern {
-        Pattern {
-            initial_at:                    None,
-            comments_after_initial_at:     LinkedList::new(),
-            arguments:                     LinkedList::new(),
-            comments_before_curly_b_close: LinkedList::new(),
-            comments_before_end_at:        LinkedList::new(),
-            end_at:                        None,
-        }
-    }
-}
-
-fn parse(
-    build_ctx: &crate::builder::BuildCtx,
-    node: &rnix::SyntaxNode,
-) -> Pattern {
-    let mut pattern = Pattern::default();
-
-    let mut children = crate::children::Children::new_with_configuration(
-        build_ctx, node, true,
-    );
-
-    // x @
-    let child = children.peek_next().unwrap();
-    if let rnix::SyntaxKind::NODE_PAT_BIND = child.element.kind() {
-        pattern.initial_at = Some(child.element);
-        children.move_next();
-    }
-
-    // /**/
-    children.drain_comments_and_newlines(|element| match element {
-        crate::children::DrainCommentOrNewline::Comment(text) => {
-            pattern.comments_after_initial_at.push_back(text);
-        }
-        crate::children::DrainCommentOrNewline::Newline(_) => {}
-    });
-
-    // {
-    children.move_next();
-
-    // arguments
-    loop {
-        let mut argument = Argument::default();
-
-        // Before an item we can have: comma, comments, whitespace
-        loop {
-            let child = children.peek_next().unwrap();
-            // eprintln!("before item {:?}", child.element.kind());
-
-            match child.element.kind() {
-                rnix::SyntaxKind::NODE_PAT_ENTRY
-                | rnix::SyntaxKind::TOKEN_CURLY_B_CLOSE
-                | rnix::SyntaxKind::TOKEN_ELLIPSIS => {
-                    break;
-                }
-                rnix::SyntaxKind::TOKEN_COMMA => {
-                    children.move_next();
-                }
-                rnix::SyntaxKind::TOKEN_COMMENT => {
-                    let content =
-                        child.element.into_token().unwrap().to_string();
-
-                    argument.comments_before.push_back(content);
-                    children.move_next();
-                }
-                rnix::SyntaxKind::TOKEN_WHITESPACE => {
-                    children.move_next();
-                }
-                _ => {}
-            }
-        }
-
-        // item
-        let child = children.peek_next().unwrap();
-        // eprintln!("item {:?}", child.element.kind());
-        match child.element.kind() {
-            rnix::SyntaxKind::TOKEN_CURLY_B_CLOSE => {
-                pattern.comments_before_curly_b_close =
-                    argument.comments_before;
-                break;
-            }
-            rnix::SyntaxKind::TOKEN_ELLIPSIS
-            | rnix::SyntaxKind::NODE_PAT_ENTRY => {
-                argument.item = Some(child.element);
-                children.move_next();
-            }
-            _ => {}
-        }
-
-        // After an item we can have: comma, comments, whitespace
-        loop {
-            let child = children.peek_next().unwrap();
-            // eprintln!("after item {:?}", child.element.kind());
-
-            match child.element.kind() {
-                rnix::SyntaxKind::NODE_PAT_ENTRY
-                | rnix::SyntaxKind::TOKEN_ELLIPSIS
-                | rnix::SyntaxKind::TOKEN_CURLY_B_CLOSE => {
-                    break;
-                }
-                rnix::SyntaxKind::TOKEN_COMMA => {
-                    children.move_next();
-                }
-                rnix::SyntaxKind::TOKEN_COMMENT => {
-                    let content =
-                        child.element.into_token().unwrap().to_string();
-
-                    children.move_next();
-                    argument.comment_after = Some(content);
-                    break;
-                }
-                rnix::SyntaxKind::TOKEN_WHITESPACE => {
-                    let content =
-                        child.element.into_token().unwrap().to_string();
-
-                    children.move_next();
-                    if crate::utils::count_newlines(&content) > 0 {
-                        break;
-                    }
-                }
-                _ => {}
-            }
-        }
-
-        pattern.arguments.push_back(argument);
-    }
-
-    // /**/
-    children.drain_comments_and_newlines(|element| match element {
-        crate::children::DrainCommentOrNewline::Comment(text) => {
-            pattern.comments_before_curly_b_close.push_back(text);
-        }
-        crate::children::DrainCommentOrNewline::Newline(_) => {}
-    });
-
-    // }
-    children.move_next();
-
-    // /**/
-    children.drain_comments_and_newlines(|element| match element {
-        crate::children::DrainCommentOrNewline::Comment(text) => {
-            pattern.comments_before_end_at.push_back(text);
-        }
-        crate::children::DrainCommentOrNewline::Newline(_) => {}
-    });
-
-    // @ x
-    if let Some(child) = children.peek_next() {
-        if let rnix::SyntaxKind::NODE_PAT_BIND = child.element.kind() {
-            pattern.end_at = Some(child.element);
-        }
-    }
-
-    pattern
-}
-
 pub fn rule(
     build_ctx: &crate::builder::BuildCtx,
     node: &rnix::SyntaxNode,
 ) -> std::collections::LinkedList<crate::builder::Step> {
     let mut steps = std::collections::LinkedList::new();
 
-    let pattern = parse(build_ctx, node);
+    let pattern = crate::parsers::pattern::parse(build_ctx, node);
 
     let has_comments_between_curly_b =
         pattern.arguments.iter().any(|argument| {