diff --git a/.trae/rules/project_rules.md b/.trae/rules/project_rules.md
index 04b37f1..2c4cfa4 100644
--- a/.trae/rules/project_rules.md
+++ b/.trae/rules/project_rules.md
@@ -47,3 +47,54 @@ Common Options:
       --dry-run                  Do not actually run the command
       --build-graph              Generate build graph
 
+# Project Agents.md Guide
+
+This is a [MoonBit](https://docs.moonbitlang.com) project.
+
+## Project Structure
+
+- MoonBit packages are organized per directory, for each directory, there is a
+  `package.json` file listing its dependencies. Each package has its files and
+  blackbox test files (common, ending in `_test.mbt`) and whitebox test files
+  (ending in `_wbtest.mbt`).
+
+- In the toplevel directory, this is a `moon.mod.json` file listing about the
+  module and some meta information.
+
+## Coding convention
+
+- MoonBit code is organized in block style, each block is separated by `///|`,
+  the order of each block is irrelevant. In some refactorings, you can process
+  block by block independently.
+
+- Try to keep deprecated blocks in file called `deprecated.mbt` in each
+  directory.
+
+## Tooling
+
+- `moon fmt` is used to format your code properly.
+
+- `moon info` is used to update the generated interface of the package, each
+  package has a generated interface file `.mbti`, it is a brief formal
+  description of the package. If nothing in `.mbti` changes, this means your
+  change does not bring the visible changes to the external package users, it is
+  typically a safe refactoring.
+
+- In the last step, run `moon info && moon fmt` to update the interface and
+  format the code. Check the diffs of `.mbti` file to see if the changes are
+  expected.
+
+- Run `moon test` to check the test is passed. MoonBit supports snapshot
+  testing, so when your changes indeed change the behavior of the code, you
+  should run `moon test --update` to update the snapshot.
+
+- You can run `moon check` to check the code is linted correctly.
+
+- When writing tests, you are encouraged to use `inspect` and run
+  `moon test --update` to update the snapshots, only use assertions like
+  `assert_eq` when you are in some loops where each snapshot may vary. You can
+  use `moon coverage analyze > uncovered.log` to see which parts of your code
+  are not covered by tests.
+
+- agent-todo.md has some small tasks that are easy for AI to pick up, agent is
+  welcome to finish the tasks and check the box when you are done
diff --git a/moon.mod.json b/moon.mod.json
index 3919046..6cbf4b5 100644
--- a/moon.mod.json
+++ b/moon.mod.json
@@ -1,9 +1,8 @@
 {
   "name": "oboard/moonbit-eval",
-  "version": "0.8.11",
+  "version": "0.8.13",
   "deps": {
     "moonbitlang/parser": "0.1.11",
-    "oboard/mio": "0.4.3",
     "bobzhang/zip": "0.1.0"
   },
   "readme": "README.md",
diff --git a/src/example/main.mbt b/src/example/main.mbt
new file mode 100644
index 0000000..e8e2b4d
--- /dev/null
+++ b/src/example/main.mbt
@@ -0,0 +1,5 @@
+///|
+fn main {
+  let result = @eval.MoonBitVM::new().eval("1 + 2")
+  println(result)
+}
diff --git a/src/example/moon.pkg.json b/src/example/moon.pkg.json
new file mode 100644
index 0000000..b9ca184
--- /dev/null
+++ b/src/example/moon.pkg.json
@@ -0,0 +1,9 @@
+{
+  "is-main": true,
+  "import": [
+    {
+      "path": "oboard/moonbit-eval",
+      "alias": "eval"
+    }
+  ]
+}
\ No newline at end of file
diff --git a/src/example/pkg.generated.mbti b/src/example/pkg.generated.mbti
new file mode 100644
index 0000000..e68579c
--- /dev/null
+++ b/src/example/pkg.generated.mbti
@@ -0,0 +1,13 @@
+// Generated using `moon info`, DON'T EDIT IT
+package "oboard/moonbit-eval/example"
+
+// Values
+
+// Errors
+
+// Types and methods
+
+// Type aliases
+
+// Traits
+
diff --git a/src/export.mbt b/src/export.mbt
index 70976b7..d843182 100644
--- a/src/export.mbt
+++ b/src/export.mbt
@@ -21,6 +21,14 @@ pub fn eval_result_to_string(result : EvalResult) -> String {
   }
 }
 
+///|
+pub fn code_to_ast(code : String) -> String {
+  match @interpreter.parse_code_to_impl(code) {
+    Ok(i) => i.to_json().stringify()
+    Err(msg) => msg
+  }
+}
+
 ///|
 pub fn add_extern_fn(
   vm : MoonBitVM,
diff --git a/src/moon.pkg.json b/src/moon.pkg.json
index 7961e60..aba1ba1 100644
--- a/src/moon.pkg.json
+++ b/src/moon.pkg.json
@@ -10,6 +10,7 @@
         "create",
         "eval",
         "eval_result_to_string",
+        "code_to_ast",
         "add_extern_fn",
         "add_embedded_fn",
         "add_embedded_method",
diff --git a/src/mooncakes/loader.mbt b/src/mooncakes/loader.mbt
deleted file mode 100644
index 693c879..0000000
--- a/src/mooncakes/loader.mbt
+++ /dev/null
@@ -1,189 +0,0 @@
-///|
-pub async fn load_meta(
-  mod_name : String,
-  version? : String,
-) -> @interpreter.ModuleInfo {
-  ///|
-  let mod_name = mod_name + (if version is Some(v) { "@" + v } else { "" })
-  // 获取模块元信息
-  let url = "https://mooncakes.io/assets/\{mod_name}/resource.json"
-  let info = try? @mio.get(url).unwrap_json()
-  if info is Ok({ "meta_info": meta_info, .. }) {
-    @json.from_json(meta_info)
-  } else {
-    @interpreter.ModuleInfo::new("")
-  }
-}
-
-///|
-pub async fn load_module(
-  mod_name : String,
-  version? : String,
-) -> Map[String, @interpreter.RuntimeModule] {
-  let mod_name = mod_name + (if version is Some(v) { "@" + v } else { "" })
-  let modules : Map[String, @interpreter.RuntimeModule] = {}
-
-  // 获取模块元信息
-  let meta = load_meta(mod_name, version?)
-
-  // 处理依赖模块
-  if meta.deps is Some(deps) {
-    // for name, version in deps {
-    let deps = deps.to_array()
-    while deps.pop() is Some((name, version)) {
-      let dep_modules = load_module(name, version~)
-      for name, dep_module in dep_modules {
-        modules.set(name, dep_module)
-      }
-    }
-  }
-  let url = "https://mooncakes.io/assets/\{mod_name}/module_index.json"
-  let module_index = @mio.get(url).unwrap_json()
-  let pkgs : Map[String, @interpreter.RuntimePackage] = {}
-
-  // Parse package information from module_index.json recursively
-  async fn parse_child(
-    child : Json,
-    pkgs : Map[String, @interpreter.RuntimePackage],
-  ) {
-    if child is { "childs": Array(childs), .. } {
-      while childs.pop() is Some(sub_child) {
-        parse_child(sub_child, pkgs)
-      }
-    }
-    if child is { "name": String(pkg_name), "package": package_info, .. } {
-      if package_info is { "path": String(path), .. } {
-        match load_package(path, pkgs) {
-          Some(pkg) => pkgs.set(pkg_name, pkg)
-          None => ()
-        }
-      }
-    }
-  }
-
-  parse_child(module_index, pkgs)
-  modules.set(mod_name, @interpreter.RuntimeModule::{ meta, pkgs })
-  modules
-}
-
-///|
-pub async fn load_package(
-  pkg_name : String,
-  deps : Map[String, @interpreter.RuntimePackage],
-) -> @interpreter.RuntimePackage? {
-  let url = "https://mooncakes.io/assets/\{pkg_name}/resource.json"
-  let info = @mio.get(url).unwrap_json()
-  let sources : Map[String, String] = {}
-  if info is { "source_files": Array(source_files), .. } {
-    while source_files.pop() is Some(file) {
-      if file is String(name) {
-        let source = @mio.get(
-          "https://mooncakes.io/assets/\{pkg_name}/\{name}.html",
-        ).text() catch {
-          _ => ""
-        }
-        let start = source.find("<pre><code class=\"moonbit\">")
-        let end = source.rev_find("</code></pre>")
-        if (start, end) is (Some(start), Some(end)) {
-          sources.set(name, source[start:end].to_string())
-        }
-      }
-    }
-    Some({
-      name: pkg_name,
-      traits: Map::new(),
-      fn_aliases: Map::new(),
-      type_aliases: Map::new(),
-      trait_aliases: Map::new(),
-      stubs: Map::new(),
-      trait_methods: Map::new(),
-      type_definitions: Map::new(),
-      type_derived_traits: Map::new(),
-      constructors: Map::new(),
-      struct_methods: Map::new(),
-      values: Map::new(),
-      env: @interpreter.RuntimeEnvironment::new(),
-      deps,
-      files: sources,
-      loaded: false,
-    })
-  } else {
-    None
-  }
-}
-
-///|
-pub async fn load_module_zip(
-  mod_name : String,
-  version? : String,
-) -> @interpreter.RuntimeModule {
-  let module_name = mod_name + (if version is Some(v) { "@" + v } else { "" })
-  if (try? load_meta(module_name)) is Ok(a) {
-    let res = try? @mio.get(a.get_zip_url())
-    if res is Ok(res) {
-      if (try? @zip.Archive::of_bytes(res.data)) is Ok(zip) {
-        if zip.find(@fpath.Fpath("moon.mod.json")) is Some(m) {
-          if m.kind() is File(data) {
-            let module_info : @interpreter.ModuleInfo = @json.from_json(
-              @json.parse(@encoding/utf8.decode(data.to_bytes())),
-            ) catch {
-              _ => abort("Failed to read moon.mod.json")
-            }
-            // println(module_info)
-            let root = if module_info.source is Some(source) {
-              source
-            } else {
-              ""
-            }
-            // println(root)
-            fn collect_files(root : String) -> Map[String, String] {
-              let files = {}
-              for entry in zip.to_array() {
-                if entry.kind() is File(file) {
-                  let path = entry.path().to_string()
-                  if path.has_prefix(root) && path.has_suffix(".mbt") {
-                    try {
-                      files[path] = @encoding/utf8.decode(file.to_bytes())
-                    } catch {
-                      _ => abort("Failed to decode file content")
-                    }
-                  }
-                }
-              }
-              files
-            }
-            // 找出所有的 packages
-            fn scan_packages() -> Array[@interpreter.RuntimePackage] {
-              let pkgs = []
-              for entry in zip.to_array() {
-                if entry.is_dir() {
-                  let dir = entry.path().to_string()
-                  if zip.find(@fpath.Fpath(dir + "moon.pkg.json")) is Some(_) {
-                    let pkg_name = module_name +
-                      dir.strip_prefix(root).unwrap_or(dir).to_string()
-                    // println(pkg_name)
-                    // println(dir)
-                    pkgs.push(
-                      @interpreter.RuntimePackage::new(
-                        pkg_name,
-                        files=collect_files(dir),
-                      ),
-                    )
-                  }
-                }
-              }
-              pkgs
-            }
-
-            let packages = scan_packages()
-            return @interpreter.RuntimeModule::{
-              meta: a,
-              pkgs: Map::from_array(packages.map(pkg => (pkg.name, pkg))),
-            }
-          }
-        }
-      }
-    }
-  }
-  abort("Failed to load module zip")
-}
diff --git a/src/mooncakes/moon.pkg.json b/src/mooncakes/moon.pkg.json
deleted file mode 100644
index 9d895a7..0000000
--- a/src/mooncakes/moon.pkg.json
+++ /dev/null
@@ -1,10 +0,0 @@
-{
-  "import": [
-    "oboard/moonbit-eval/interpreter",
-    "oboard/mio",
-    "bobzhang/zip",
-    "bobzhang/zip/types/fpath",
-    "bobzhang/zip/member",
-    "bobzhang/zip/file"
-  ]
-}
\ No newline at end of file
diff --git a/src/mooncakes/pkg.generated.mbti b/src/mooncakes/pkg.generated.mbti
deleted file mode 100644
index 7d76d53..0000000
--- a/src/mooncakes/pkg.generated.mbti
+++ /dev/null
@@ -1,24 +0,0 @@
-// Generated using `moon info`, DON'T EDIT IT
-package "oboard/moonbit-eval/mooncakes"
-
-import(
-  "oboard/moonbit-eval/interpreter"
-)
-
-// Values
-async fn load_meta(String, version? : String) -> @interpreter.ModuleInfo
-
-async fn load_module(String, version? : String) -> Map[String, @interpreter.RuntimeModule]
-
-async fn load_module_zip(String, version? : String) -> @interpreter.RuntimeModule
-
-async fn load_package(String, Map[String, @interpreter.RuntimePackage]) -> @interpreter.RuntimePackage?
-
-// Errors
-
-// Types and methods
-
-// Type aliases
-
-// Traits
-
diff --git a/src/pkg.generated.mbti b/src/pkg.generated.mbti
index 973df8f..d26589f 100644
--- a/src/pkg.generated.mbti
+++ b/src/pkg.generated.mbti
@@ -13,6 +13,8 @@ fn add_embedded_method(MoonBitVM, String, String, (@interpreter.RuntimeFunctionC
 
 fn add_extern_fn(MoonBitVM, String, (@interpreter.RuntimeFunctionContext) -> @interpreter.RuntimeValue raise @interpreter.ControlFlow) -> Unit
 
+fn code_to_ast(String) -> String
+
 fn eval_result_to_string(EvalResult) -> String
 
 fn expr_to_string(@syntax.Expr) -> String
diff --git a/src/test/moon.pkg.json b/src/test/moon.pkg.json
index 7749243..ee595af 100644
--- a/src/test/moon.pkg.json
+++ b/src/test/moon.pkg.json
@@ -4,8 +4,6 @@
       "path": "oboard/moonbit-eval",
       "alias": "eval"
     },
-    "oboard/moonbit-eval/interpreter",
-    "oboard/mio",
-    "oboard/moonbit-eval/mooncakes"
+    "oboard/moonbit-eval/interpreter"
   ]
 }
\ No newline at end of file
diff --git a/src/test/packages.mbt b/src/test/packages.mbt
index f1ca664..86b4686 100644
--- a/src/test/packages.mbt
+++ b/src/test/packages.mbt
@@ -54,20 +54,20 @@ test "cross_package_method_calling" {
   assert_eq(vm.eval("arr1.length()").to_string(), "5")
 }
 
-///|
-test "online_package" {
-  let vm = MoonBitVM::new()
-  @mio.run(() => {
-    let modules = try? @mooncakes.load_module("wangweigang/hello")
-    if modules is Ok(modules) {
-      vm.interpreter.main_pkg.deps.set(
-        "hello",
-        modules.get("wangweigang/hello").unwrap().pkgs["hello"],
-      )
-      println(vm.eval("@hello.hello()"))
-    }
-  })
-}
+// ///|
+// test "online_package" {
+//   let vm = MoonBitVM::new()
+//   @mio.run(() => {
+//     let modules = try? @mooncakes.load_module("wangweigang/hello")
+//     if modules is Ok(modules) {
+//       vm.interpreter.main_pkg.deps.set(
+//         "hello",
+//         modules.get("wangweigang/hello").unwrap().pkgs["hello"],
+//       )
+//       println(vm.eval("@hello.hello()"))
+//     }
+//   })
+// }
 
 // ///|
 // test {