diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index ac4d048..a487220 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -24,6 +24,7 @@ jobs:
       - uses: arduino/setup-task@v1
         with:
           repo-token: ${{ github.token }}
+      - run: sudo apt update
       - run: sudo apt install -qq -y libudev-dev
       - run: task test
 
@@ -37,6 +38,7 @@ jobs:
       - uses: arduino/setup-task@v1
         with:
           repo-token: ${{ github.token }}
+      - run: sudo apt update
       - run: sudo apt install -qq -y libudev-dev
       - run: task lint
 
diff --git a/src/commands/new.rs b/src/commands/new.rs
index fb654a8..ad5157f 100644
--- a/src/commands/new.rs
+++ b/src/commands/new.rs
@@ -25,10 +25,11 @@ pub fn cmd_new(args: &NewArgs) -> Result<()> {
         Lang::Go => new_go(&args.name).context("new Go project")?,
         Lang::Rust => new_rust(&args.name).context("new Rust project")?,
         Lang::Zig => new_zig(&args.name).context("new Zig project")?,
-        Lang::TS => todo!("TypeScript is not supported yet"),
+        Lang::TS => bail!("TypeScript is not supported yet"),
         Lang::C => new_c(&args.name).context("new C project")?,
         Lang::Cpp => new_cpp(&args.name).context("new C++ project")?,
-        Lang::Python => todo!("Python is not supported yet"),
+        Lang::Python => bail!("Python is not supported yet"),
+        Lang::Moon => bail!("Moon starter project is not supported yet"),
     }
     write_config(&args.name)?;
     init_git(&args.name)?;
diff --git a/src/config.rs b/src/config.rs
index b8be6ba..fa128dd 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -183,4 +183,5 @@ pub enum Lang {
     C,
     Cpp,
     Python,
+    Moon,
 }
diff --git a/src/langs.rs b/src/langs.rs
index 9c11677..92e0990 100644
--- a/src/langs.rs
+++ b/src/langs.rs
@@ -28,6 +28,7 @@ pub fn build_bin(config: &Config, args: &BuildArgs) -> anyhow::Result<()> {
         Lang::C => build_c(config),
         Lang::Cpp => build_cpp(config),
         Lang::Python => build_python(config),
+        Lang::Moon => build_moon(config),
     }?;
     let bin_path = config.rom_path.join(BIN);
     if !bin_path.is_file() {
@@ -36,7 +37,9 @@ pub fn build_bin(config: &Config, args: &BuildArgs) -> anyhow::Result<()> {
     if !args.no_strip {
         strip_custom(&bin_path)?;
     }
-    if !args.no_opt {
+    // TODO(@orsinium): Moon binaries cannot be parsed by wasm-opt, figure out why.
+    //     [parse exception: block cannot pop from outside (at 0:7745)]
+    if !args.no_opt && !matches!(lang, Lang::Moon) {
         optimize(&bin_path).context("optimize wasm binary")?;
     }
     Ok(())
@@ -65,6 +68,12 @@ fn detect_lang(root: &Path) -> anyhow::Result<Lang> {
     if root.join("pyproject.toml").exists() {
         return Ok(Lang::Python);
     }
+    if root.join("moon.pkg.json").exists() {
+        return Ok(Lang::Moon);
+    }
+    if root.join("moon.mod.json").exists() {
+        return Ok(Lang::Moon);
+    }
     if root.join("main.c").exists() {
         return Ok(Lang::C);
     }
@@ -308,6 +317,7 @@ fn find_wasi_sdk() -> anyhow::Result<PathBuf> {
     Ok(path)
 }
 
+// Build Zig project.
 fn build_zig(config: &Config) -> anyhow::Result<()> {
     check_installed("Zig", "zig", "version")?;
     let mut cmd_args = vec!["build"];
@@ -331,6 +341,43 @@ fn build_zig(config: &Config) -> anyhow::Result<()> {
     Ok(())
 }
 
+// Build Moon project.
+fn build_moon(config: &Config) -> anyhow::Result<()> {
+    check_installed("Moon", "moon", "version")?;
+    let mut cmd_args = vec!["build", "--target", "wasm"];
+    if let Some(additional_args) = &config.compile_args {
+        for arg in additional_args {
+            cmd_args.push(arg.as_str());
+        }
+    }
+    let output = Command::new("moon")
+        .args(cmd_args)
+        .current_dir(&config.root_path)
+        .output()
+        .context("run moon build")?;
+    check_output(&output)?;
+
+    let from_dir = config
+        .root_path
+        .join("target")
+        .join("wasm")
+        .join("release")
+        .join("build");
+    let from_path = find_wasm(&from_dir)?;
+    let out_path = config.rom_path.join(BIN);
+    std::fs::copy(&from_path, out_path).context("copy wasm binary")?;
+    std::fs::remove_file(from_path).context("remove wasm file")?;
+    Ok(())
+}
+
+fn build_ts(_config: &Config) -> anyhow::Result<()> {
+    todo!("TypeScript is not supported yet")
+}
+
+fn build_python(_config: &Config) -> anyhow::Result<()> {
+    todo!("Python is not supported yet")
+}
+
 /// Find a wasm binary in the given directory.
 fn find_wasm(from_dir: &Path) -> anyhow::Result<PathBuf> {
     let from_dir = std::fs::read_dir(from_dir)?;
@@ -353,14 +400,6 @@ fn find_wasm(from_dir: &Path) -> anyhow::Result<PathBuf> {
     }
 }
 
-fn build_ts(_config: &Config) -> anyhow::Result<()> {
-    todo!("TypeScript is not supported yet")
-}
-
-fn build_python(_config: &Config) -> anyhow::Result<()> {
-    todo!("Python is not supported yet")
-}
-
 /// Convert a file system path to UTF-8 if possible.
 pub fn path_to_utf8(path: &Path) -> anyhow::Result<&str> {
     match path.to_str() {