diff --git a/rust/Cargo.lock b/rust/Cargo.lock
index 52c6fef..837436a 100644
--- a/rust/Cargo.lock
+++ b/rust/Cargo.lock
@@ -8,6 +8,15 @@ version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0c4b4d0bd25bd0b74681c0ad21497610ce1b7c91b1022cd21c80c6fbdd9476b0"
 
+[[package]]
+name = "convert_case"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec182b0ca2f35d8fc196cf3404988fd8b8c739a4d270ff118a398feb0cbec1ca"
+dependencies = [
+ "unicode-segmentation",
+]
+
 [[package]]
 name = "linked_list_allocator"
 version = "0.10.5"
@@ -34,6 +43,16 @@ dependencies = [
  "linked_list_allocator",
 ]
 
+[[package]]
+name = "prettyplease"
+version = "0.2.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5f12335488a2f3b0a83b14edad48dca9879ce89b2edd10e80237e4e852dd645e"
+dependencies = [
+ "proc-macro2",
+ "syn 2.0.72",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.86"
@@ -78,6 +97,17 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "syn"
+version = "2.0.72"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc4b9b9bf2add8093d3f2c0204471e951b2285580335de42f9d2534f3ae7a8af"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
 [[package]]
 name = "testbed"
 version = "0.1.0"
@@ -92,6 +122,12 @@ version = "1.0.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
 
+[[package]]
+name = "unicode-segmentation"
+version = "1.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d4c87d22b6e3f4a18d4d40ef354e97c90fcb14dd91d7dc0aa9d8a1172ebf7202"
+
 [[package]]
 name = "yellowstone"
 version = "0.1.0"
@@ -99,6 +135,7 @@ dependencies = [
  "mammoth",
  "yunq",
  "yunq-derive",
+ "yunqc",
 ]
 
 [[package]]
@@ -115,5 +152,16 @@ version = "0.1.0"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 1.0.109",
+]
+
+[[package]]
+name = "yunqc"
+version = "0.1.0"
+dependencies = [
+ "convert_case",
+ "prettyplease",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.72",
 ]
diff --git a/rust/lib/yellowstone/Cargo.toml b/rust/lib/yellowstone/Cargo.toml
index c464a9e..59ea732 100644
--- a/rust/lib/yellowstone/Cargo.toml
+++ b/rust/lib/yellowstone/Cargo.toml
@@ -8,3 +8,6 @@ mammoth = { path = "../mammoth" }
 yunq = {path = "../yunq"}
 yunq-derive = {path = "../yunq-derive"}
 
+[build-dependencies]
+yunqc = {path = "../../../yunq/rust"}
+
diff --git a/rust/lib/yellowstone/build.rs b/rust/lib/yellowstone/build.rs
index a072a3a..24472ac 100644
--- a/rust/lib/yellowstone/build.rs
+++ b/rust/lib/yellowstone/build.rs
@@ -1,18 +1,14 @@
-use std::process::Command;
+use std::fs;
 
 fn main() {
+    let input_file = "../../../sys/yellowstone/lib/yellowstone/yellowstone.yunq";
+
+    println!("cargo::rerun-if-changed={input_file}");
+
+    let input = fs::read_to_string(input_file).expect("Failed to read input file");
+
+    let code = yunqc::codegen(&input).expect("Failed to generate yunq code.");
+
     let out = std::env::var("OUT_DIR").unwrap() + "/yunq.rs";
-
-    let status = Command::new("cargo")
-        .current_dir("../../../yunq/rust")
-        .arg("run")
-        .arg("--")
-        .arg("--input-path")
-        .arg("../../sys/yellowstone/lib/yellowstone/yellowstone.yunq")
-        .arg("--output-path")
-        .arg(out)
-        .status()
-        .expect("Failed to start execution");
-
-    assert!(status.success());
+    fs::write(out, code).expect("Failed to write generated code.");
 }
diff --git a/yunq/rust/Cargo.lock b/yunq/rust/Cargo.lock
index 145ddd8..cfaa503 100644
--- a/yunq/rust/Cargo.lock
+++ b/yunq/rust/Cargo.lock
@@ -255,7 +255,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bec47e5bfd1bff0eeaf6d8b485cc1074891a197ab4225d504cb7a1ab88b02bf0"
 
 [[package]]
-name = "yunq"
+name = "yunqc"
 version = "0.1.0"
 dependencies = [
  "clap",
diff --git a/yunq/rust/Cargo.toml b/yunq/rust/Cargo.toml
index 2550596..a972f93 100644
--- a/yunq/rust/Cargo.toml
+++ b/yunq/rust/Cargo.toml
@@ -1,12 +1,20 @@
 [package]
-name = "yunq"
+name = "yunqc"
 version = "0.1.0"
 edition = "2021"
 
 [dependencies]
-clap = { version = "4.5.7", features = ["derive"] }
 convert_case = "0.6.0"
 prettyplease = "0.2.20"
 proc-macro2 = { version = "1.0" }
 quote = { version = "1.0" }
 syn = "2.0.72"
+
+clap = { version = "4.5.7", features = ["derive"], optional = true}
+
+[features]
+build-binary = ["clap"]
+
+[[bin]]
+name = "yunqc"
+required-features = ["build-binary"]
diff --git a/yunq/rust/src/lib.rs b/yunq/rust/src/lib.rs
new file mode 100644
index 0000000..07ecdb9
--- /dev/null
+++ b/yunq/rust/src/lib.rs
@@ -0,0 +1,15 @@
+mod codegen;
+mod lexer;
+mod parser;
+
+use std::error::Error;
+
+pub fn codegen(input: &str) -> Result<String, Box<dyn Error>> {
+    let tokens = lexer::lex_input(input)?;
+
+    let mut ast_parser = parser::Parser::new(&tokens);
+    ast_parser.parse_ast()?;
+    ast_parser.type_check()?;
+
+    Ok(codegen::generate_code(ast_parser.ast()))
+}
diff --git a/yunq/rust/src/main.rs b/yunq/rust/src/main.rs
index 21ece22..a835985 100644
--- a/yunq/rust/src/main.rs
+++ b/yunq/rust/src/main.rs
@@ -1,7 +1,3 @@
-mod codegen;
-mod lexer;
-mod parser;
-
 use std::error::Error;
 use std::fs;
 
@@ -22,13 +18,8 @@ struct Args {
 fn main() -> Result<(), Box<dyn Error>> {
     let args = Args::parse();
     let input = fs::read_to_string(args.input_path)?;
-    let tokens = lexer::lex_input(&input)?;
 
-    let mut ast_parser = parser::Parser::new(&tokens);
-    ast_parser.parse_ast()?;
-    ast_parser.type_check()?;
-
-    let code = codegen::generate_code(ast_parser.ast());
+    let code = yunqc::codegen(&input)?;
 
     fs::write(args.output_path, code)?;