diff --git a/.github/workflows/release-crates.yml b/.github/workflows/release-crates.yml
index c37b58a2..a8605cc3 100644
--- a/.github/workflows/release-crates.yml
+++ b/.github/workflows/release-crates.yml
@@ -32,11 +32,11 @@ jobs:
           sudo apt-get install llvm
       - name: Publish crates
         run: |
-          cargo publish --no-verify -p sync-ls || true
           cargo publish --no-verify -p typst-shim || true
           cargo publish --no-verify -p tinymist-derive || true
           cargo publish --no-verify -p tinymist-l10n || true
           cargo publish --no-verify -p tinymist-std || true
+          cargo publish --no-verify -p sync-ls || true
           cargo publish --no-verify -p tinymist-package || true
           cargo publish --no-verify -p tinymist-vfs || true
           cargo publish --no-verify -p tinymist-world || true
@@ -56,11 +56,11 @@ jobs:
           cargo publish --no-verify -p tinymist-cli || true
       - name: Verifies crate health (Optional)
         run: |
-          cargo publish --dry-run -p sync-ls
           cargo publish --dry-run -p typst-shim
           cargo publish --dry-run -p tinymist-derive
           cargo publish --dry-run -p tinymist-l10n
           cargo publish --dry-run -p tinymist-std
+          cargo publish --dry-run -p sync-ls
           cargo publish --dry-run -p tinymist-vfs
           cargo publish --dry-run -p tinymist-package
           cargo publish --dry-run -p tinymist-world
diff --git a/Cargo.lock b/Cargo.lock
index 2c501357..ab3cd231 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3872,14 +3872,17 @@ dependencies = [
  "crossbeam-channel",
  "dapts",
  "futures",
+ "js-sys",
  "log",
  "lsp-types",
  "parking_lot",
  "serde",
+ "serde-wasm-bindgen",
  "serde_json",
  "tinymist-std",
  "tokio",
  "tokio-util",
+ "wasm-bindgen",
 ]
 
 [[package]]
diff --git a/crates/sync-lsp/Cargo.toml b/crates/sync-lsp/Cargo.toml
index ae4fcf2f..8211308a 100644
--- a/crates/sync-lsp/Cargo.toml
+++ b/crates/sync-lsp/Cargo.toml
@@ -27,12 +27,16 @@ tinymist-std.workspace = true
 clap = { workspace = true, optional = true }
 tokio = { workspace = true, features = ["rt"], optional = true }
 tokio-util = { workspace = true, optional = true }
+js-sys = { workspace = true, optional = true }
+wasm-bindgen = { workspace = true, optional = true }
+serde-wasm-bindgen = { workspace = true, optional = true }
 
 [features]
 dap = ["dapts"]
 lsp = ["lsp-types"]
 server = ["tokio"]
-system = ["tokio", "tokio/time", "tokio-util", "clap"]
+system = ["tokio", "tokio/time", "tokio-util", "clap", "tinymist-std/system"]
+web = ["js-sys", "wasm-bindgen", "serde-wasm-bindgen", "tinymist-std/web"]
 
 [package.metadata.docs.rs]
 features = ["dap", "lsp", "system", "server"]
diff --git a/crates/sync-lsp/src/lib.rs b/crates/sync-lsp/src/lib.rs
index fa97c2bf..1bc71b41 100644
--- a/crates/sync-lsp/src/lib.rs
+++ b/crates/sync-lsp/src/lib.rs
@@ -28,3 +28,24 @@ pub use crate::msg::ResponseError;
 pub type LspResult<T> = Result<T, ResponseError>;
 /// The common event type for language servers.
 pub type Event = Box<dyn Any + Send>;
+
+/// Note that we must have our logging only write out to stderr.
+#[cfg(feature = "web")]
+fn dummy_transport<M: TryFrom<Message, Error = anyhow::Error> + GetMessageKind>() -> Connection<M> {
+    let (event_sender, event_receiver) = crossbeam_channel::bounded::<crate::Event>(0);
+    let (writer_sender, writer_receiver) = crossbeam_channel::bounded::<Message>(0);
+    Connection {
+        // lsp_sender,
+        // lsp_receiver,
+        sender: TConnectionTx {
+            event: event_sender,
+            lsp: writer_sender,
+            marker: std::marker::PhantomData,
+        },
+        receiver: TConnectionRx {
+            event: event_receiver,
+            lsp: writer_receiver,
+            marker: std::marker::PhantomData,
+        },
+    }
+}
diff --git a/crates/sync-lsp/src/lsp.rs b/crates/sync-lsp/src/lsp.rs
index ba6dae6a..bd31358e 100644
--- a/crates/sync-lsp/src/lsp.rs
+++ b/crates/sync-lsp/src/lsp.rs
@@ -6,8 +6,8 @@ use serde::de::DeserializeOwned;
 use serde::{Deserialize, Serialize};
 
 use crate::{
-    invalid_data_fmt, read_msg_text, write_msg_text, ExtractError, LspOrDapResponse, RequestId,
-    ResponseError,
+    invalid_data_fmt, read_msg_text, write_msg_text, ExtractError, LspOrDapResponse, LspResult,
+    RequestId, ResponseError,
 };
 
 /// A message in the Language Server Protocol.
@@ -134,26 +134,19 @@ pub struct Response {
 }
 
 impl Response {
-    /// Creates a response with the success payload.
-    pub fn new_ok<R: serde::Serialize>(id: RequestId, result: R) -> Response {
-        Response {
-            id,
-            result: Some(serde_json::to_value(result).unwrap()),
-            error: None,
-        }
-    }
-
-    /// Creates a response with the failure reason.
-    pub fn new_err(id: RequestId, code: i32, message: String) -> Response {
-        let error = ResponseError {
-            code,
-            message,
-            data: None,
-        };
-        Response {
-            id,
-            result: None,
-            error: Some(error),
+    /// Creates a response
+    pub fn new(id: RequestId, result: LspResult<serde_json::Value>) -> Response {
+        match result {
+            Ok(result) => Response {
+                id,
+                result: Some(result),
+                error: None,
+            },
+            Err(err) => Response {
+                id,
+                result: None,
+                error: Some(err),
+            },
         }
     }
 }
diff --git a/crates/sync-lsp/src/msg.rs b/crates/sync-lsp/src/msg.rs
index a5340953..021d2d4d 100644
--- a/crates/sync-lsp/src/msg.rs
+++ b/crates/sync-lsp/src/msg.rs
@@ -185,21 +185,17 @@ pub enum MessageKind {
 /// Gets the kind of the message.
 pub trait GetMessageKind {
     /// Returns the kind of the message.
-    fn get_message_kind() -> MessageKind;
+    const MESSAGE_KIND: MessageKind;
 }
 
 #[cfg(feature = "lsp")]
 impl GetMessageKind for LspMessage {
-    fn get_message_kind() -> MessageKind {
-        MessageKind::Lsp
-    }
+    const MESSAGE_KIND: MessageKind = MessageKind::Lsp;
 }
 
 #[cfg(feature = "dap")]
 impl GetMessageKind for DapMessage {
-    fn get_message_kind() -> MessageKind {
-        MessageKind::Dap
-    }
+    const MESSAGE_KIND: MessageKind = MessageKind::Dap;
 }
 
 #[allow(unused)]
diff --git a/crates/sync-lsp/src/server.rs b/crates/sync-lsp/src/server.rs
index 4ffc9d75..98f2157e 100644
--- a/crates/sync-lsp/src/server.rs
+++ b/crates/sync-lsp/src/server.rs
@@ -11,6 +11,8 @@ use std::any::Any;
 use std::collections::HashMap;
 use std::path::{Path, PathBuf};
 use std::pin::Pin;
+#[cfg(feature = "web")]
+use std::sync::atomic::AtomicU32;
 use std::sync::{Arc, Weak};
 
 use futures::future::MaybeDone;
@@ -19,8 +21,6 @@ use serde::Serialize;
 use serde_json::{from_value, Value as JsonValue};
 use tinymist_std::time::Instant;
 
-#[cfg(feature = "lsp")]
-use crate::lsp::{Notification, Request};
 use crate::msg::*;
 use crate::req_queue;
 use crate::*;
@@ -35,6 +35,8 @@ pub type LspResponseFuture<T> = LspResult<ResponseFuture<T>>;
 pub type SchedulableResponse<T> = LspResponseFuture<LspResult<T>>;
 /// The common response future type for language servers.
 pub type AnySchedulableResponse = SchedulableResponse<JsonValue>;
+/// The result of a scheduling response
+pub type ScheduleResult = AnySchedulableResponse;
 /// The result of a scheduled response which could be finally caught by
 /// `schedule_tail`.
 /// - Returns Ok(Some()) -> Already responded
@@ -152,15 +154,7 @@ impl<S: 'static> TypedLspClient<S> {
 
     /// Sends a event to the client itself.
     pub fn send_event<T: std::any::Any + Send + 'static>(&self, event: T) {
-        let Some(sender) = self.sender.upgrade() else {
-            log::warn!("failed to send request: connection closed");
-            return;
-        };
-
-        let Err(res) = sender.event.send(Box::new(event)) else {
-            return;
-        };
-        log::warn!("failed to send event: {res:?}");
+        self.sender.send_event(event);
     }
 }
 
@@ -181,6 +175,8 @@ impl<S> std::ops::Deref for TypedLspClient<S> {
     }
 }
 
+// send_request: Function,
+// send_notification: Function,
 /// The root of the language server host.
 /// Will close connection when dropped.
 #[derive(Debug, Clone)]
@@ -198,8 +194,27 @@ impl LspClientRoot {
         let _strong = Arc::new(sender.into());
         let weak = LspClient {
             handle,
-            msg_kind: M::get_message_kind(),
-            sender: Arc::downgrade(&_strong),
+            msg_kind: M::MESSAGE_KIND,
+            sender: TransportHost::System(SystemTransportSender {
+                sender: Arc::downgrade(&_strong),
+            }),
+            req_queue: Arc::new(Mutex::new(ReqQueue::default())),
+
+            hook: Arc::new(()),
+        };
+        Self { weak, _strong }
+    }
+
+    /// Creates a new language server host from js.
+    #[cfg(feature = "web")]
+    pub fn new_js(handle: tokio::runtime::Handle, transport: JsTransportSender) -> Self {
+        let dummy = dummy_transport::<LspMessage>();
+
+        let _strong = Arc::new(dummy.sender.into());
+        let weak = LspClient {
+            handle,
+            msg_kind: LspMessage::MESSAGE_KIND,
+            sender: TransportHost::Js(transport),
             req_queue: Arc::new(Mutex::new(ReqQueue::default())),
 
             hook: Arc::new(()),
@@ -222,6 +237,166 @@ impl LspClientRoot {
 type ReqHandler = Box<dyn for<'a> FnOnce(&'a mut dyn Any, LspOrDapResponse) + Send + Sync>;
 type ReqQueue = req_queue::ReqQueue<(String, Instant), ReqHandler>;
 
+#[derive(Debug, Clone)]
+enum TransportHost {
+    System(SystemTransportSender),
+    #[cfg(feature = "web")]
+    Js(JsTransportSender),
+}
+
+#[derive(Debug, Clone)]
+struct SystemTransportSender {
+    pub(crate) sender: Weak<ConnectionTx>,
+}
+
+/// Creates a new js transport host.
+#[cfg(feature = "web")]
+#[derive(Debug, Clone)]
+pub struct JsTransportSender {
+    event_id: Arc<AtomicU32>,
+    events: Arc<Mutex<HashMap<u32, Event>>>,
+    pub(crate) sender_event: js_sys::Function,
+    pub(crate) sender_request: js_sys::Function,
+    pub(crate) sender_notification: js_sys::Function,
+}
+
+#[cfg(feature = "web")]
+impl JsTransportSender {
+    /// Creates a new JS transport host.
+    pub fn new(
+        sender_event: js_sys::Function,
+        sender_request: js_sys::Function,
+        sender_notification: js_sys::Function,
+    ) -> Self {
+        Self {
+            event_id: Arc::new(AtomicU32::new(0)),
+            events: Arc::new(Mutex::new(HashMap::new())),
+            sender_event,
+            sender_request,
+            sender_notification,
+        }
+    }
+}
+
+#[cfg(feature = "web")]
+/// SAFETY:
+/// This is only safe if the `JsTransportHost` is used in a single thread.
+unsafe impl Send for TransportHost {}
+
+#[cfg(feature = "web")]
+/// SAFETY:
+/// This is only safe if the `JsTransportHost` is used in a single thread.
+unsafe impl Sync for TransportHost {}
+
+impl TransportHost {
+    /// Sends a event to the server itself.
+    pub fn send_event<T: std::any::Any + Send + 'static>(&self, event: T) {
+        match self {
+            TransportHost::System(host) => {
+                let Some(sender) = host.sender.upgrade() else {
+                    log::warn!("failed to send request: connection closed");
+                    return;
+                };
+
+                if let Err(res) = sender.event.send(Box::new(event)) {
+                    log::warn!("failed to send event: {res:?}");
+                }
+            }
+            #[cfg(feature = "web")]
+            TransportHost::Js(host) => {
+                let event_id = {
+                    let event_id = host
+                        .event_id
+                        .fetch_add(1, std::sync::atomic::Ordering::SeqCst);
+                    let mut lg = host.events.lock();
+                    lg.insert(event_id, Box::new(event));
+                    js_sys::Number::from(event_id)
+                };
+                if let Err(err) = host
+                    .sender_event
+                    .call1(&wasm_bindgen::JsValue::UNDEFINED, &event_id.into())
+                {
+                    log::error!("failed to send event: {err:?}");
+                }
+            }
+        }
+    }
+
+    pub fn send_message(&self, response: Message) {
+        match self {
+            TransportHost::System(host) => {
+                let Some(sender) = host.sender.upgrade() else {
+                    log::warn!("failed to send response: connection closed");
+                    return;
+                };
+                if let Err(res) = sender.lsp.send(response) {
+                    log::warn!("failed to send response: {res:?}");
+                }
+            }
+            #[cfg(feature = "web")]
+            TransportHost::Js(host) => match response {
+                #[cfg(feature = "lsp")]
+                Message::Lsp(lsp::Message::Request(req)) => {
+                    let msg = to_js_value(&req).expect("failed to serialize request to js value");
+                    if let Err(err) = host
+                        .sender_request
+                        .call1(&wasm_bindgen::JsValue::UNDEFINED, &msg)
+                    {
+                        log::error!("failed to send request: {err:?}");
+                    }
+                }
+                #[cfg(feature = "lsp")]
+                Message::Lsp(lsp::Message::Notification(req)) => {
+                    let msg = to_js_value(&req).expect("failed to serialize request to js value");
+                    if let Err(err) = host
+                        .sender_notification
+                        .call1(&wasm_bindgen::JsValue::UNDEFINED, &msg)
+                    {
+                        log::error!("failed to send request: {err:?}");
+                    }
+                }
+                #[cfg(feature = "lsp")]
+                Message::Lsp(lsp::Message::Response(req)) => {
+                    panic!("unexpected response to js world: {req:?}");
+                }
+                #[cfg(feature = "dap")]
+                Message::Dap(dap::Message::Request(req)) => {
+                    let msg = to_js_value(&req).expect("failed to serialize request to js value");
+                    if let Err(err) = host
+                        .sender_request
+                        .call1(&wasm_bindgen::JsValue::UNDEFINED, &msg)
+                    {
+                        log::error!("failed to send request: {err:?}");
+                    }
+                }
+                #[cfg(feature = "dap")]
+                Message::Dap(dap::Message::Event(req)) => {
+                    let msg = to_js_value(&req).expect("failed to serialize request to js value");
+                    if let Err(err) = host
+                        .sender_notification
+                        .call1(&wasm_bindgen::JsValue::UNDEFINED, &msg)
+                    {
+                        log::error!("failed to send request: {err:?}");
+                    }
+                }
+                #[cfg(feature = "dap")]
+                Message::Dap(dap::Message::Response(req)) => {
+                    panic!("unexpected response to js world: {req:?}");
+                }
+            },
+        }
+    }
+}
+
+// todo: poor performance, struct -> serde_json -> serde_wasm_bindgen ->
+// serialize -> deserialize??
+#[cfg(feature = "web")]
+fn to_js_value<T: serde::Serialize>(
+    value: &T,
+) -> Result<wasm_bindgen::JsValue, serde_wasm_bindgen::Error> {
+    value.serialize(&serde_wasm_bindgen::Serializer::new().serialize_maps_as_objects(true))
+}
+
 /// The host for the language server, or known as the LSP client.
 #[derive(Debug, Clone)]
 pub struct LspClient {
@@ -229,7 +404,7 @@ pub struct LspClient {
     pub handle: tokio::runtime::Handle,
 
     pub(crate) msg_kind: MessageKind,
-    pub(crate) sender: Weak<ConnectionTx>,
+    sender: TransportHost,
     pub(crate) req_queue: Arc<Mutex<ReqQueue>>,
 
     pub(crate) hook: Arc<dyn LsHook>,
@@ -261,14 +436,7 @@ impl LspClient {
 
     /// Sends a event to the server itself.
     pub fn send_event<T: std::any::Any + Send + 'static>(&self, event: T) {
-        let Some(sender) = self.sender.upgrade() else {
-            log::warn!("failed to send request: connection closed");
-            return;
-        };
-
-        if let Err(res) = sender.event.send(Box::new(event)) {
-            log::warn!("failed to send event: {res:?}");
-        }
+        self.sender.send_event(event);
     }
 
     /// Completes an server2client request in the request queue.
@@ -308,19 +476,11 @@ impl LspClient {
             .register(id.clone(), (method.to_owned(), received_at));
     }
 
-    /// Responds a typed result to the client.
-    pub fn respond_result<T: Serialize>(&self, id: RequestId, result: LspResult<T>) {
-        let result = result.and_then(|t| serde_json::to_value(t).map_err(internal_error));
-        self.respond_any_result(id, result);
-    }
-
-    fn respond_any_result(&self, id: RequestId, result: LspResult<JsonValue>) {
+    fn respond_result(&self, id: RequestId, result: LspResult<JsonValue>) {
         let req_id = id.clone();
         let msg: Message = match (self.msg_kind, result) {
             #[cfg(feature = "lsp")]
-            (MessageKind::Lsp, Ok(resp)) => lsp::Response::new_ok(id, resp).into(),
-            #[cfg(feature = "lsp")]
-            (MessageKind::Lsp, Err(e)) => lsp::Response::new_err(id, e.code, e.message).into(),
+            (MessageKind::Lsp, res) => lsp::Response::new(id, res).into(),
             #[cfg(feature = "dap")]
             (MessageKind::Dap, Ok(resp)) => dap::Response::success(RequestId::dap(id), resp).into(),
             #[cfg(feature = "dap")]
@@ -341,53 +501,28 @@ impl LspClient {
 
         self.hook.stop_request(&id, &method, received_at);
 
-        let Some(sender) = self.sender.upgrade() else {
-            log::warn!("failed to send response ({method}, {id}): connection closed");
-            return;
-        };
-        if let Err(res) = sender.lsp.send(response) {
-            log::warn!("failed to send response ({method}, {id}): {res:?}");
-        }
+        self.sender.send_message(response);
     }
 }
 
 impl LspClient {
-    /// Schedules a request from the client.
-    pub fn schedule<T: Serialize + 'static>(
-        &self,
-        req_id: RequestId,
-        resp: SchedulableResponse<T>,
-    ) -> ScheduledResult {
-        let resp = resp?;
-
-        use futures::future::MaybeDone::*;
-        match resp {
-            Done(output) => {
-                self.respond_result(req_id, output);
-            }
-            Future(fut) => {
-                let client = self.clone();
-                let req_id = req_id.clone();
-                self.handle.spawn(async move {
-                    client.respond_result(req_id, fut.await);
-                });
-            }
-            Gone => {
-                log::warn!("response for request({req_id:?}) already taken");
-            }
-        };
-
-        Ok(Some(()))
-    }
-
     /// Finally sends the response if it is not sent before.
     /// From the definition, the response is already sent if it is `Some(())`.
-    pub fn schedule_tail(&self, req_id: RequestId, resp: ScheduledResult) {
+    pub async fn schedule_tail(self, req_id: RequestId, resp: ScheduleResult) {
         match resp {
-            // Already responded
-            Ok(Some(())) => {}
-            // The requests that doesn't start.
-            _ => self.respond_result(req_id, resp),
+            Ok(MaybeDone::Done(result)) => {
+                self.respond_result(req_id, result);
+            }
+            Ok(MaybeDone::Future(result)) => {
+                self.respond_result(req_id, result.await);
+            }
+            Ok(MaybeDone::Gone) => {
+                log::warn!("response for request({req_id:?}) already taken");
+                self.respond_result(req_id, Err(internal_error("response already taken")));
+            }
+            Err(err) => {
+                self.respond_result(req_id, Err(err));
+            }
         }
     }
 }
@@ -429,9 +564,9 @@ impl LsHook for () {
 }
 
 type AsyncHandler<S, T, R> = fn(srv: &mut S, args: T) -> SchedulableResponse<R>;
-type RawHandler<S, T> = fn(srv: &mut S, req_id: RequestId, args: T) -> ScheduledResult;
+type RawHandler<S, T> = fn(srv: &mut S, args: T) -> ScheduleResult;
 type BoxPureHandler<S, T> = Box<dyn Fn(&mut S, T) -> LspResult<()>>;
-type BoxHandler<S, T> = Box<dyn Fn(&mut S, &LspClient, RequestId, T) -> ScheduledResult>;
+type BoxHandler<S, T> = Box<dyn Fn(&mut S, T) -> SchedulableResponse<JsonValue>>;
 type ExecuteCmdMap<S> = HashMap<&'static str, BoxHandler<S, Vec<JsonValue>>>;
 type RegularCmdMap<S> = HashMap<&'static str, BoxHandler<S, JsonValue>>;
 type NotifyCmdMap<S> = HashMap<&'static str, BoxPureHandler<S, JsonValue>>;
@@ -510,26 +645,14 @@ where
         self
     }
 
-    /// Registers a raw resource handler.
-    pub fn with_resource_(
-        mut self,
-        path: ImmutPath,
-        handler: RawHandler<Args::S, Vec<JsonValue>>,
-    ) -> Self {
-        self.resource_handlers.insert(path, raw_to_boxed(handler));
-        self
-    }
-
     /// Registers an async resource handler.
     pub fn with_resource(
         mut self,
         path: &'static str,
         handler: fn(&mut Args::S, Vec<JsonValue>) -> AnySchedulableResponse,
     ) -> Self {
-        self.resource_handlers.insert(
-            Path::new(path).into(),
-            Box::new(move |s, client, req_id, req| client.schedule(req_id, handler(s, req))),
-        );
+        self.resource_handlers
+            .insert(Path::new(path).into(), Box::new(handler));
         self
     }
 
@@ -639,7 +762,7 @@ impl<M, Args: Initializer> LsDriver<M, Args> {
 
     /// Get static resources with help of tinymist service, for example, a
     /// static help pages for some typst function.
-    pub fn get_resources(&mut self, req_id: RequestId, args: Vec<JsonValue>) -> ScheduledResult {
+    pub fn get_resources(&mut self, args: Vec<JsonValue>) -> ScheduleResult {
         let s = self.state.opt_mut().ok_or_else(not_initialized)?;
 
         let path =
@@ -651,7 +774,7 @@ impl<M, Args: Initializer> LsDriver<M, Args> {
         };
 
         // Note our redirection will keep the first path argument in the args vec.
-        handler(s, &self.client, req_id, args)
+        handler(s, args)
     }
 }
 
@@ -701,8 +824,24 @@ fn from_json<T: serde::de::DeserializeOwned>(json: JsonValue) -> LspResult<T> {
     serde_json::from_value(json).map_err(invalid_request)
 }
 
-fn raw_to_boxed<S: 'static, T: 'static>(handler: RawHandler<S, T>) -> BoxHandler<S, T> {
-    Box::new(move |s, _client, req_id, req| handler(s, req_id, req))
+/// Erases the response type to a generic `JsonValue`.
+pub fn erased_response<T: Serialize + 'static>(resp: SchedulableResponse<T>) -> ScheduleResult {
+    /// Responds a typed result to the client.
+    fn map_respond_result<T: Serialize>(result: LspResult<T>) -> LspResult<JsonValue> {
+        result.and_then(|t| serde_json::to_value(t).map_err(internal_error))
+    }
+
+    let resp = resp?;
+
+    use futures::future::MaybeDone::*;
+    Ok(match resp {
+        Done(result) => MaybeDone::Done(map_respond_result(result)),
+        Future(fut) => MaybeDone::Future(Box::pin(async move { map_respond_result(fut.await) })),
+        Gone => {
+            log::warn!("response already taken");
+            MaybeDone::Done(Err(internal_error("response already taken")))
+        }
+    })
 }
 
 fn resp_err(code: ErrorCode, msg: impl fmt::Display) -> ResponseError {
diff --git a/crates/sync-lsp/src/server/dap_srv.rs b/crates/sync-lsp/src/server/dap_srv.rs
index f6d34269..230a2cc7 100644
--- a/crates/sync-lsp/src/server/dap_srv.rs
+++ b/crates/sync-lsp/src/server/dap_srv.rs
@@ -12,14 +12,7 @@ impl<S: 'static> TypedLspClient<S> {
 
     /// Sends an untyped dap_event to the client.
     pub fn send_dap_event_(&self, evt: dap::Event) {
-        let method = &evt.event;
-        let Some(sender) = self.sender.upgrade() else {
-            log::warn!("failed to send dap event ({method}): connection closed");
-            return;
-        };
-        if let Err(res) = sender.lsp.send(evt.into()) {
-            log::warn!("failed to send dap event: {res:?}");
-        }
+        self.sender.send_message(evt.into());
     }
 }
 
@@ -27,16 +20,6 @@ impl<Args: Initializer> LsBuilder<DapMessage, Args>
 where
     Args::S: 'static,
 {
-    /// Registers an raw event handler.
-    pub fn with_command_(
-        mut self,
-        cmd: &'static str,
-        handler: RawHandler<Args::S, Vec<JsonValue>>,
-    ) -> Self {
-        self.command_handlers.insert(cmd, raw_to_boxed(handler));
-        self
-    }
-
     /// Registers an async command handler.
     pub fn with_command<R: Serialize + 'static>(
         mut self,
@@ -45,7 +28,7 @@ where
     ) -> Self {
         self.command_handlers.insert(
             cmd,
-            Box::new(move |s, client, req_id, req| client.schedule(req_id, handler(s, req))),
+            Box::new(move |s, req| erased_response(handler(s, req))),
         );
         self
     }
@@ -56,7 +39,7 @@ where
         mut self,
         handler: RawHandler<Args::S, JsonValue>,
     ) -> Self {
-        self.req_handlers.insert(R::COMMAND, raw_to_boxed(handler));
+        self.req_handlers.insert(R::COMMAND, Box::new(handler));
         self
     }
 
@@ -65,11 +48,11 @@ where
     /// request.
     pub fn with_request_<R: dapts::IRequest>(
         mut self,
-        handler: fn(&mut Args::S, RequestId, R::Arguments) -> ScheduledResult,
+        handler: fn(&mut Args::S, R::Arguments) -> ScheduleResult,
     ) -> Self {
         self.req_handlers.insert(
             R::COMMAND,
-            Box::new(move |s, _client, req_id, req| handler(s, req_id, from_json(req)?)),
+            Box::new(move |s, req| handler(s, from_json(req)?)),
         );
         self
     }
@@ -81,9 +64,7 @@ where
     ) -> Self {
         self.req_handlers.insert(
             R::COMMAND,
-            Box::new(move |s, client, req_id, req| {
-                client.schedule(req_id, handler(s, from_json(req)?))
-            }),
+            Box::new(move |s, req| erased_response(handler(s, from_json(req)?))),
         );
         self
     }
@@ -100,6 +81,7 @@ where
     ///
     /// See [`transport::MirrorArgs`] for information about the record-replay
     /// feature.
+    #[cfg(feature = "system")]
     pub fn start(
         &mut self,
         inbox: TConnectionRx<DapMessage>,
@@ -133,6 +115,7 @@ where
     }
 
     /// Starts the debug adaptor on the given connection.
+    #[cfg(feature = "system")]
     pub fn start_(&mut self, inbox: TConnectionRx<DapMessage>) -> anyhow::Result<()> {
         use EventOrMessage::*;
 
@@ -156,7 +139,13 @@ where
 
                     event_handler(s, &self.client, event)?;
                 }
-                Msg(DapMessage::Request(req)) => self.on_request(loop_start, req),
+                Msg(DapMessage::Request(req)) => {
+                    let client = self.client.clone();
+                    let req_id = (req.seq as i32).into();
+                    client.register_request(&req.command, &req_id, loop_start);
+                    let fut = client.schedule_tail(req_id, self.on_request(req));
+                    self.client.handle.spawn(fut);
+                }
                 Msg(DapMessage::Event(not)) => {
                     self.on_event(loop_start, not)?;
                 }
@@ -180,12 +169,8 @@ where
 
     /// Registers and handles a request. This should only be called once per
     /// incoming request.
-    fn on_request(&mut self, request_received: Instant, req: dap::Request) {
-        let req_id = (req.seq as i32).into();
-        self.client
-            .register_request(&req.command, &req_id, request_received);
-
-        let resp = match (&mut self.state, &*req.command) {
+    fn on_request(&mut self, req: dap::Request) -> ScheduleResult {
+        match (&mut self.state, &*req.command) {
             (State::Uninitialized(args), dapts::request::Initialize::COMMAND) => {
                 // todo: what will happen if the request cannot be deserialized?
                 let params = serde_json::from_value::<Args::I>(req.arguments);
@@ -240,22 +225,18 @@ where
                     break 'serve_req just_result(Err(method_not_found()));
                 };
 
-                let result = handler(s, &self.client, req_id.clone(), req.arguments);
-                self.client.schedule_tail(req_id, result);
+                let resp = handler(s, req.arguments);
 
                 if is_disconnect {
                     self.state = State::ShuttingDown;
                 }
 
-                return;
+                resp
             }
             (State::ShuttingDown, _) => {
                 just_result(Err(invalid_request("server is shutting down")))
             }
-        };
-
-        let result = self.client.schedule(req_id.clone(), resp);
-        self.client.schedule_tail(req_id, result);
+        }
     }
 
     /// Handles an incoming event.
diff --git a/crates/sync-lsp/src/server/lsp_srv.rs b/crates/sync-lsp/src/server/lsp_srv.rs
index 4d6f5a54..8494304f 100644
--- a/crates/sync-lsp/src/server/lsp_srv.rs
+++ b/crates/sync-lsp/src/server/lsp_srv.rs
@@ -4,19 +4,6 @@ use lsp_types::{notification::Notification as Notif, request::Request as Req, *}
 
 type PureHandler<S, T> = fn(srv: &mut S, args: T) -> LspResult<()>;
 
-/// Converts a `ScheduledResult` to a `SchedulableResponse`.
-macro_rules! reschedule {
-    ($expr:expr) => {
-        match $expr {
-            Ok(Some(())) => return,
-            Ok(None) => Ok(futures::future::MaybeDone::Done(Ok(
-                serde_json::Value::Null,
-            ))),
-            Err(e) => Err(e),
-        }
-    };
-}
-
 impl<S: 'static> TypedLspClient<S> {
     /// Sends a request to the client and registers a handler handled by the
     /// service `S`.
@@ -45,13 +32,7 @@ impl LspClient {
             Box::new(|s, resp| handler(s, resp.try_into().unwrap())),
         );
 
-        let Some(sender) = self.sender.upgrade() else {
-            log::warn!("failed to send request: connection closed");
-            return;
-        };
-        if let Err(res) = sender.lsp.send(request.into()) {
-            log::warn!("failed to send request: {res:?}");
-        }
+        self.sender.send_message(request.into());
     }
 
     /// Completes an client2server request in the request queue.
@@ -66,14 +47,7 @@ impl LspClient {
 
     /// Sends an untyped notification to the client.
     pub fn send_notification_(&self, notif: lsp::Notification) {
-        let method = &notif.method;
-        let Some(sender) = self.sender.upgrade() else {
-            log::warn!("failed to send notification ({method}): connection closed");
-            return;
-        };
-        if let Err(res) = sender.lsp.send(notif.into()) {
-            log::warn!("failed to send notification: {res:?}");
-        }
+        self.sender.send_message(notif.into());
     }
 }
 
@@ -87,7 +61,7 @@ where
         cmd: &'static str,
         handler: RawHandler<Args::S, Vec<JsonValue>>,
     ) -> Self {
-        self.command_handlers.insert(cmd, raw_to_boxed(handler));
+        self.command_handlers.insert(cmd, Box::new(handler));
         self
     }
 
@@ -99,7 +73,7 @@ where
     ) -> Self {
         self.command_handlers.insert(
             cmd,
-            Box::new(move |s, client, req_id, req| client.schedule(req_id, handler(s, req))),
+            Box::new(move |s, req| erased_response(handler(s, req))),
         );
         self
     }
@@ -125,7 +99,7 @@ where
     /// Registers a raw request handler that handlers a kind of untyped lsp
     /// request.
     pub fn with_raw_request<R: Req>(mut self, handler: RawHandler<Args::S, JsonValue>) -> Self {
-        self.req_handlers.insert(R::METHOD, raw_to_boxed(handler));
+        self.req_handlers.insert(R::METHOD, Box::new(handler));
         self
     }
 
@@ -134,11 +108,11 @@ where
     /// request.
     pub fn with_request_<R: Req>(
         mut self,
-        handler: fn(&mut Args::S, RequestId, R::Params) -> ScheduledResult,
+        handler: fn(&mut Args::S, R::Params) -> ScheduleResult,
     ) -> Self {
         self.req_handlers.insert(
             R::METHOD,
-            Box::new(move |s, _client, req_id, req| handler(s, req_id, from_json(req)?)),
+            Box::new(move |s, req| handler(s, from_json(req)?)),
         );
         self
     }
@@ -150,9 +124,7 @@ where
     ) -> Self {
         self.req_handlers.insert(
             R::METHOD,
-            Box::new(move |s, client, req_id, req| {
-                client.schedule(req_id, handler(s, from_json(req)?))
-            }),
+            Box::new(move |s, req| erased_response(handler(s, from_json(req)?))),
         );
         self
     }
@@ -247,10 +219,21 @@ where
 
                     event_handler(s, &self.client, event)?;
                 }
-                Msg(LspMessage::Request(req)) => self.on_lsp_request(loop_start, req),
+                Msg(LspMessage::Request(req)) => {
+                    let client = self.client.clone();
+                    let req_id = req.id.clone();
+                    client.register_request(&req.method, &req_id, loop_start);
+                    let fut =
+                        client.schedule_tail(req_id, self.on_lsp_request(&req.method, req.params));
+                    self.client.handle.spawn(fut);
+                }
                 Msg(LspMessage::Notification(not)) => {
                     let is_exit = not.method == EXIT_METHOD;
-                    self.on_notification(loop_start, not)?;
+                    self.client.hook.start_notification(&not.method);
+                    let result = self.on_notification(&not.method, not.params);
+                    self.client
+                        .hook
+                        .stop_notification(&not.method, loop_start, result);
                     if is_exit {
                         return Ok(());
                     }
@@ -273,17 +256,45 @@ where
         Ok(())
     }
 
+    /// Handles an incoming server event.
+    #[cfg(feature = "web")]
+    pub fn on_server_event(&mut self, event_id: u32) {
+        let evt = match &self.client.sender {
+            TransportHost::Js(sender) => sender.events.lock().remove(&event_id),
+            TransportHost::System(_) => {
+                panic!("cannot send server event in system transport");
+            }
+        };
+
+        if let Some(event) = evt {
+            let Some(event_handler) = self.events.get(&event.as_ref().type_id()) else {
+                log::warn!("unhandled event: {:?}", event.as_ref().type_id());
+                return;
+            };
+
+            let s = match &mut self.state {
+                State::Uninitialized(u) => ServiceState::Uninitialized(u.as_deref_mut()),
+                State::Initializing(s) | State::Ready(s) => ServiceState::Ready(s),
+                State::ShuttingDown => {
+                    log::warn!("server is shutting down");
+                    return;
+                }
+            };
+
+            let res = event_handler(s, &self.client, event);
+            if let Err(err) = res {
+                log::error!("failed to handle server event {event_id}: {err}");
+            }
+        }
+    }
+
     /// Registers and handles a request. This should only be called once per
     /// incoming request.
-    pub fn on_lsp_request(&mut self, request_received: Instant, req: Request) {
-        self.client
-            .register_request(&req.method, &req.id, request_received);
-
-        let req_id = req.id.clone();
-        let resp = match (&mut self.state, &*req.method) {
+    pub fn on_lsp_request(&mut self, method: &str, params: JsonValue) -> ScheduleResult {
+        match (&mut self.state, method) {
             (State::Uninitialized(args), request::Initialize::METHOD) => {
                 // todo: what will happen if the request cannot be deserialized?
-                let params = serde_json::from_value::<Args::I>(req.params);
+                let params = serde_json::from_value::<Args::I>(params);
                 match params {
                     Ok(params) => {
                         let args = args.take().expect("already initialized");
@@ -301,11 +312,8 @@ where
                 just_result(Err(invalid_request("server is already initialized")))
             }
             // todo: generalize this
-            (State::Ready(..), request::ExecuteCommand::METHOD) => {
-                reschedule!(self.on_execute_command(req))
-            }
-            (State::Ready(s), _) => 'serve_req: {
-                let method = req.method.as_str();
+            (State::Ready(..), request::ExecuteCommand::METHOD) => self.on_execute_command(params),
+            (State::Ready(s), method) => 'serve_req: {
                 let is_shutdown = method == request::Shutdown::METHOD;
 
                 let Some(handler) = self.requests.get(method) else {
@@ -313,29 +321,25 @@ where
                     break 'serve_req just_result(Err(method_not_found()));
                 };
 
-                let result = handler(s, &self.client, req_id.clone(), req.params);
-                self.client.schedule_tail(req_id, result);
+                let resp = handler(s, params);
 
                 if is_shutdown {
                     self.state = State::ShuttingDown;
                 }
 
-                return;
+                resp
             }
             (State::ShuttingDown, _) => {
                 just_result(Err(invalid_request("server is shutting down")))
             }
-        };
-
-        let result = self.client.schedule(req_id.clone(), resp);
-        self.client.schedule_tail(req_id, result);
+        }
     }
 
     /// The entry point for the `workspace/executeCommand` request.
-    fn on_execute_command(&mut self, req: Request) -> ScheduledResult {
+    fn on_execute_command(&mut self, params: JsonValue) -> ScheduleResult {
         let s = self.state.opt_mut().ok_or_else(not_initialized)?;
 
-        let params = from_value::<ExecuteCommandParams>(req.params)
+        let params = from_value::<ExecuteCommandParams>(params)
             .map_err(|e| invalid_params(e.to_string()))?;
 
         let ExecuteCommandParams {
@@ -344,38 +348,28 @@ where
 
         // todo: generalize this
         if command == "tinymist.getResources" {
-            self.get_resources(req.id, arguments)
+            self.get_resources(arguments)
         } else {
             let Some(handler) = self.commands.get(command.as_str()) else {
                 log::error!("asked to execute unknown command: {command}");
                 return Err(method_not_found());
             };
-            handler(s, &self.client, req.id, arguments)
+            handler(s, arguments)
         }
     }
 
     /// Handles an incoming notification.
-    pub fn on_notification(
-        &mut self,
-        received_at: Instant,
-        not: Notification,
-    ) -> anyhow::Result<()> {
-        self.client.hook.start_notification(&not.method);
-        let handle = |s, Notification { method, params }: Notification| {
-            let Some(handler) = self.notifications.get(method.as_str()) else {
+    pub fn on_notification(&mut self, method: &str, params: JsonValue) -> LspResult<()> {
+        let handle = |s, method: &str, params: JsonValue| {
+            let Some(handler) = self.notifications.get(method) else {
                 log::warn!("unhandled notification: {method}");
                 return Ok(());
             };
 
-            let result = handler(s, params);
-            self.client
-                .hook
-                .stop_notification(&method, received_at, result);
-
-            Ok(())
+            handler(s, params)
         };
 
-        match (&mut self.state, &*not.method) {
+        match (&mut self.state, method) {
             (state, notification::Initialized::METHOD) => {
                 let mut s = State::ShuttingDown;
                 std::mem::swap(state, &mut s);
@@ -395,9 +389,9 @@ where
                         return Ok(());
                     }
                 };
-                handle(s, not)
+                handle(s, method, params)
             }
-            (State::Ready(state), _) => handle(state, not),
+            (State::Ready(state), method) => handle(state, method, params),
             // todo: whether it is safe to ignore notifications
             (State::Uninitialized(..) | State::Initializing(..), method) => {
                 log::warn!("server is not ready yet, while received notification {method}");
diff --git a/crates/sync-lsp/src/transport.rs b/crates/sync-lsp/src/transport.rs
index 4a7cc4a4..61b245cd 100644
--- a/crates/sync-lsp/src/transport.rs
+++ b/crates/sync-lsp/src/transport.rs
@@ -46,7 +46,7 @@ pub fn with_stdio_transport<M: TryFrom<Message, Error = anyhow::Error> + GetMess
     args: MirrorArgs,
     f: impl FnOnce(Connection<M>) -> anyhow::Result<()>,
 ) -> anyhow::Result<()> {
-    with_stdio_transport_impl(args, M::get_message_kind(), |conn| f(conn.into()))
+    with_stdio_transport_impl(args, M::MESSAGE_KIND, |conn| f(conn.into()))
 }
 
 /// Note that we must have our logging only write out to stderr.
diff --git a/crates/tinymist-cli/Cargo.toml b/crates/tinymist-cli/Cargo.toml
index fb85d894..680c7d56 100644
--- a/crates/tinymist-cli/Cargo.toml
+++ b/crates/tinymist-cli/Cargo.toml
@@ -62,7 +62,7 @@ strum.workspace = true
 sync-ls = { workspace = true, features = ["lsp", "server", "system"] }
 tinymist-assets = { workspace = true }
 tinymist-query.workspace = true
-tinymist-std.workspace = true
+tinymist-std = { workspace = true, default-features = false }
 tinymist = { workspace = true, default-features = false, features = ["system"] }
 tinymist-project = { workspace = true, features = ["lsp"] }
 tinymist-render.workspace = true
diff --git a/crates/tinymist/package.json b/crates/tinymist/package.json
index 2bfda616..aa56cdea 100644
--- a/crates/tinymist/package.json
+++ b/crates/tinymist/package.json
@@ -21,7 +21,7 @@
   "scripts": {
     "build:dev": "wasm-pack build --target web --dev -- --no-default-features --features web,no-content-hint",
     "build:node": "wasm-pack build --target nodejs -- --no-default-features --features web,no-content-hint",
-    "build": "wasm-pack build --target web -- --no-default-features --features web,no-content-hint",
+    "build": "wasm-pack build --target web  --dev -- --no-default-features --features web,no-content-hint",
     "publish:dry": "npm publish --dry-run",
     "publish:lib": "npm publish || exit 0",
     "test:chrome": "wasm-pack test --chrome --headless --release",
diff --git a/crates/tinymist/src/cmd.rs b/crates/tinymist/src/cmd.rs
index deef2871..a2eeccb3 100644
--- a/crates/tinymist/src/cmd.rs
+++ b/crates/tinymist/src/cmd.rs
@@ -6,7 +6,6 @@ use std::path::PathBuf;
 use lsp_types::TextDocumentIdentifier;
 use serde::Deserialize;
 use serde_json::Value as JsonValue;
-use sync_ls::RequestId;
 #[cfg(feature = "trace")]
 use task::TraceParams;
 use tinymist_assets::TYPST_PREVIEW_HTML;
@@ -23,7 +22,7 @@ use typst::syntax::{LinkedNode, Source};
 use world::TaskInputs;
 
 use super::*;
-use crate::lsp::query::{run_query, LspClientExt};
+use crate::lsp::query::run_query;
 use crate::tool::ast::AstRepr;
 
 #[cfg(feature = "system")]
@@ -86,7 +85,7 @@ struct ExportSyntaxRangeOpts {
 /// Here are implemented the handlers for each command.
 impl ServerState {
     /// Export the current document as PDF file(s).
-    pub fn export_pdf(&mut self, req_id: RequestId, mut args: Vec<JsonValue>) -> ScheduledResult {
+    pub fn export_pdf(&mut self, mut args: Vec<JsonValue>) -> ScheduleResult {
         let opts = get_arg_or_default!(args[1] as ExportOpts);
 
         let creation_timestamp = if let Some(value) = opts.creation_timestamp {
@@ -101,7 +100,6 @@ impl ServerState {
 
         let export = self.config.export_task();
         self.export(
-            req_id,
             ProjectTask::ExportPdf(ExportPdfTask {
                 export,
                 pdf_standards: pdf_standards.unwrap_or_default(),
@@ -113,11 +111,10 @@ impl ServerState {
     }
 
     /// Export the current document as HTML file(s).
-    pub fn export_html(&mut self, req_id: RequestId, mut args: Vec<JsonValue>) -> ScheduledResult {
+    pub fn export_html(&mut self, mut args: Vec<JsonValue>) -> ScheduleResult {
         let opts = get_arg_or_default!(args[1] as ExportOpts);
         let export = self.config.export_task();
         self.export(
-            req_id,
             ProjectTask::ExportHtml(ExportHtmlTask { export }),
             opts.open.unwrap_or_default(),
             args,
@@ -125,15 +122,10 @@ impl ServerState {
     }
 
     /// Export the current document as Markdown file(s).
-    pub fn export_markdown(
-        &mut self,
-        req_id: RequestId,
-        mut args: Vec<JsonValue>,
-    ) -> ScheduledResult {
+    pub fn export_markdown(&mut self, mut args: Vec<JsonValue>) -> ScheduleResult {
         let opts = get_arg_or_default!(args[1] as ExportTypliteOpts);
         let export = self.config.export_task();
         self.export(
-            req_id,
             ProjectTask::ExportMd(ExportMarkdownTask {
                 processor: opts.processor,
                 assets_path: opts.assets_path,
@@ -145,11 +137,10 @@ impl ServerState {
     }
 
     /// Export the current document as Tex file(s).
-    pub fn export_tex(&mut self, req_id: RequestId, mut args: Vec<JsonValue>) -> ScheduledResult {
+    pub fn export_tex(&mut self, mut args: Vec<JsonValue>) -> ScheduleResult {
         let opts = get_arg_or_default!(args[1] as ExportTypliteOpts);
         let export = self.config.export_task();
         self.export(
-            req_id,
             ProjectTask::ExportTeX(ExportTeXTask {
                 processor: opts.processor,
                 assets_path: opts.assets_path,
@@ -161,11 +152,10 @@ impl ServerState {
     }
 
     /// Export the current document as Text file(s).
-    pub fn export_text(&mut self, req_id: RequestId, mut args: Vec<JsonValue>) -> ScheduledResult {
+    pub fn export_text(&mut self, mut args: Vec<JsonValue>) -> ScheduleResult {
         let opts = get_arg_or_default!(args[1] as ExportOpts);
         let export = self.config.export_task();
         self.export(
-            req_id,
             ProjectTask::ExportText(ExportTextTask { export }),
             opts.open.unwrap_or_default(),
             args,
@@ -173,7 +163,7 @@ impl ServerState {
     }
 
     /// Query the current document and export the result as JSON file(s).
-    pub fn export_query(&mut self, req_id: RequestId, mut args: Vec<JsonValue>) -> ScheduledResult {
+    pub fn export_query(&mut self, mut args: Vec<JsonValue>) -> ScheduleResult {
         let opts = get_arg_or_default!(args[1] as QueryOpts);
         // todo: deprecate it
         let _ = opts.strict;
@@ -184,7 +174,6 @@ impl ServerState {
         }
 
         self.export(
-            req_id,
             ProjectTask::Query(QueryTask {
                 format: opts.format,
                 output_extension: opts.output_extension,
@@ -199,14 +188,13 @@ impl ServerState {
     }
 
     /// Export the current document as Svg file(s).
-    pub fn export_svg(&mut self, req_id: RequestId, mut args: Vec<JsonValue>) -> ScheduledResult {
+    pub fn export_svg(&mut self, mut args: Vec<JsonValue>) -> ScheduleResult {
         let opts = get_arg_or_default!(args[1] as ExportOpts);
 
         let mut export = self.config.export_task();
         select_page(&mut export, opts.page).map_err(invalid_params)?;
 
         self.export(
-            req_id,
             ProjectTask::ExportSvg(ExportSvgTask { export }),
             opts.open.unwrap_or_default(),
             args,
@@ -214,7 +202,7 @@ impl ServerState {
     }
 
     /// Export the current document as Png file(s).
-    pub fn export_png(&mut self, req_id: RequestId, mut args: Vec<JsonValue>) -> ScheduledResult {
+    pub fn export_png(&mut self, mut args: Vec<JsonValue>) -> ScheduleResult {
         let opts = get_arg_or_default!(args[1] as ExportOpts);
 
         let ppi = opts.ppi.unwrap_or(144.);
@@ -227,7 +215,6 @@ impl ServerState {
         select_page(&mut export, opts.page).map_err(invalid_params)?;
 
         self.export(
-            req_id,
             ProjectTask::ExportPng(ExportPngTask {
                 fill: opts.fill,
                 ppi,
@@ -242,14 +229,14 @@ impl ServerState {
     /// for passing the correct absolute path of typst document.
     pub fn export(
         &mut self,
-        req_id: RequestId,
+
         task: ProjectTask,
         open: bool,
         mut args: Vec<JsonValue>,
-    ) -> ScheduledResult {
+    ) -> ScheduleResult {
         let path = get_arg!(args[0] as PathBuf);
 
-        run_query!(req_id, self.OnExport(path, open, task))
+        run_query!(self.OnExport(path, open, task))
     }
 
     /// Export a range of the current document as Ansi highlighted text.
@@ -294,9 +281,7 @@ impl ServerState {
         range: Option<LspRange>,
         f: impl Fn(Source, Option<Range<usize>>) -> LspResult<T>,
     ) -> LspResult<T> {
-        let s = self
-            .query_source(path.into(), Ok)
-            .map_err(|e| internal_error(format!("cannot find source: {e}")))?;
+        let s = self.query_source(path.into(), Ok)?;
 
         // todo: cannot select syntax-sensitive data well
         // let node = LinkedNode::new(s.root());
@@ -512,11 +497,7 @@ impl ServerState {
     }
 
     /// Interact with the code context at the source file.
-    pub fn interact_code_context(
-        &mut self,
-        req_id: RequestId,
-        _arguments: Vec<JsonValue>,
-    ) -> ScheduledResult {
+    pub fn interact_code_context(&mut self, _arguments: Vec<JsonValue>) -> ScheduleResult {
         let queries = _arguments.into_iter().next().ok_or_else(|| {
             invalid_params("The first parameter is not a valid code context query array")
         })?;
@@ -533,7 +514,7 @@ impl ServerState {
         let path = as_path(params.text_document);
         let query = params.query;
 
-        run_query!(req_id, self.InteractCodeContext(path, query))
+        run_query!(self.InteractCodeContext(path, query))
     }
 
     /// Get the trace data of the document.
@@ -631,31 +612,19 @@ impl ServerState {
     }
 
     /// Get the metrics of the document.
-    pub fn get_document_metrics(
-        &mut self,
-        req_id: RequestId,
-        mut args: Vec<JsonValue>,
-    ) -> ScheduledResult {
+    pub fn get_document_metrics(&mut self, mut args: Vec<JsonValue>) -> ScheduleResult {
         let path = get_arg!(args[0] as PathBuf);
-        run_query!(req_id, self.DocumentMetrics(path))
+        run_query!(self.DocumentMetrics(path))
     }
 
     /// Get all syntactic labels in workspace.
-    pub fn get_workspace_labels(
-        &mut self,
-        req_id: RequestId,
-        _arguments: Vec<JsonValue>,
-    ) -> ScheduledResult {
-        run_query!(req_id, self.WorkspaceLabel())
+    pub fn get_workspace_labels(&mut self, _arguments: Vec<JsonValue>) -> ScheduleResult {
+        run_query!(self.WorkspaceLabel())
     }
 
     /// Get the server info.
-    pub fn get_server_info(
-        &mut self,
-        req_id: RequestId,
-        _arguments: Vec<JsonValue>,
-    ) -> ScheduledResult {
-        run_query!(req_id, self.ServerInfo())
+    pub fn get_server_info(&mut self, _arguments: Vec<JsonValue>) -> ScheduleResult {
+        run_query!(self.ServerInfo())
     }
 }
 
diff --git a/crates/tinymist/src/input.rs b/crates/tinymist/src/input.rs
index b660257f..6055fc07 100644
--- a/crates/tinymist/src/input.rs
+++ b/crates/tinymist/src/input.rs
@@ -111,10 +111,10 @@ impl ServerState {
     pub fn query_source<T>(
         &self,
         path: ImmutPath,
-        f: impl FnOnce(Source) -> Result<T>,
-    ) -> Result<T> {
+        f: impl FnOnce(Source) -> LspResult<T>,
+    ) -> LspResult<T> {
         let snapshot = self.memory_changes.get(&path);
-        let snapshot = snapshot.ok_or_else(|| anyhow::anyhow!("file missing {path:?}"))?;
+        let snapshot = snapshot.ok_or_else(|| internal_error(format!("file missing {path:?}")))?;
         let source = snapshot.clone();
         f(source)
     }
diff --git a/crates/tinymist/src/lsp/init.rs b/crates/tinymist/src/lsp/init.rs
index 5062ef17..d58e4ea5 100644
--- a/crates/tinymist/src/lsp/init.rs
+++ b/crates/tinymist/src/lsp/init.rs
@@ -91,10 +91,10 @@ impl Initializer for SuperInit {
         } = self;
         let const_config = config.const_config.clone();
         // Bootstrap server
-        let service = ServerState::main(client, config, err.is_none());
+        let state = ServerState::main(client, config, err.is_none());
 
         if let Some(err) = err {
-            return (service, Err(err));
+            return (state, Err(err));
         }
 
         let semantic_tokens_provider = (!const_config.tokens_dynamic_registration).then(|| {
@@ -209,6 +209,6 @@ impl Initializer for SuperInit {
         };
 
         let res = serde_json::to_value(res).map_err(|e| invalid_params(e.to_string()));
-        (service, just_result(res))
+        (state, just_result(res))
     }
 }
diff --git a/crates/tinymist/src/lsp/query.rs b/crates/tinymist/src/lsp/query.rs
index 748f5035..1428d5ab 100644
--- a/crates/tinymist/src/lsp/query.rs
+++ b/crates/tinymist/src/lsp/query.rs
@@ -1,6 +1,5 @@
 //! tinymist's language server
 
-use futures::future::MaybeDone;
 use lsp_types::request::GotoDeclarationParams;
 use lsp_types::*;
 use serde::{Deserialize, Serialize};
@@ -8,223 +7,134 @@ use sync_ls::*;
 use tinymist_query::{
     CompilerQueryRequest, CompilerQueryResponse, FoldRequestFeature, SyntaxRequest,
 };
-use tinymist_std::{ImmutPath, Result};
+use tinymist_std::ImmutPath;
 
 use crate::project::{EntryState, TaskInputs, DETACHED_ENTRY};
 use crate::{as_path, as_path_, as_path_pos, FormatterMode, ServerState};
 
 /// The future type for a lsp query.
-pub type QueryFuture = Result<ResponseFuture<Result<CompilerQueryResponse>>>;
-
-pub trait LspClientExt {
-    fn schedule_query(&self, req_id: RequestId, query_fut: QueryFuture) -> ScheduledResult;
-}
-
-impl LspClientExt for LspClient {
-    /// Schedules a query from the client.
-    fn schedule_query(&self, req_id: RequestId, query_fut: QueryFuture) -> ScheduledResult {
-        let fut = query_fut.map_err(|e| internal_error(e.to_string()))?;
-        let fut: SchedulableResponse<CompilerQueryResponse> = Ok(match fut {
-            MaybeDone::Done(res) => {
-                MaybeDone::Done(res.map_err(|err| internal_error(err.to_string())))
-            }
-            MaybeDone::Future(fut) => MaybeDone::Future(Box::pin(async move {
-                let res = fut.await;
-                res.map_err(|err| internal_error(err.to_string()))
-            })),
-            MaybeDone::Gone => MaybeDone::Gone,
-        });
-        self.schedule(req_id, fut)
-    }
-}
+pub type QueryFuture = SchedulableResponse<CompilerQueryResponse>;
 
 macro_rules! run_query {
-    ($req_id: ident, $self: ident.$query: ident ($($arg_key:ident),* $(,)?)) => {{
+    ($self: ident.$query: ident ($($arg_key:ident),* $(,)?)) => {{
         use tinymist_query::*;
         let req = paste::paste! { [<$query Request>] { $($arg_key),* } };
-        let query_fut = $self.query(CompilerQueryRequest::$query(req.clone()));
-        $self.client.untyped().schedule_query($req_id, query_fut)
+        erased_response($self.query(CompilerQueryRequest::$query(req.clone())))
     }};
 }
 pub(crate) use run_query;
 
 /// LSP Standard Language Features
 impl ServerState {
-    pub(crate) fn goto_definition(
-        &mut self,
-        req_id: RequestId,
-        params: GotoDefinitionParams,
-    ) -> ScheduledResult {
+    pub(crate) fn goto_definition(&mut self, params: GotoDefinitionParams) -> ScheduleResult {
         let (path, position) = as_path_pos(params.text_document_position_params);
-        run_query!(req_id, self.GotoDefinition(path, position))
+        run_query!(self.GotoDefinition(path, position))
     }
 
-    pub(crate) fn goto_declaration(
-        &mut self,
-        req_id: RequestId,
-        params: GotoDeclarationParams,
-    ) -> ScheduledResult {
+    pub(crate) fn goto_declaration(&mut self, params: GotoDeclarationParams) -> ScheduleResult {
         let (path, position) = as_path_pos(params.text_document_position_params);
-        run_query!(req_id, self.GotoDeclaration(path, position))
+        run_query!(self.GotoDeclaration(path, position))
     }
 
-    pub(crate) fn references(
-        &mut self,
-        req_id: RequestId,
-        params: ReferenceParams,
-    ) -> ScheduledResult {
+    pub(crate) fn references(&mut self, params: ReferenceParams) -> ScheduleResult {
         let (path, position) = as_path_pos(params.text_document_position);
-        run_query!(req_id, self.References(path, position))
+        run_query!(self.References(path, position))
     }
 
-    pub(crate) fn hover(&mut self, req_id: RequestId, params: HoverParams) -> ScheduledResult {
+    pub(crate) fn hover(&mut self, params: HoverParams) -> ScheduleResult {
         let (path, position) = as_path_pos(params.text_document_position_params);
         self.implicit_focus_entry(|| Some(path.as_path().into()), 'h');
 
         self.implicit_position = Some(position);
-        run_query!(req_id, self.Hover(path, position))
+        run_query!(self.Hover(path, position))
     }
 
-    pub(crate) fn folding_range(
-        &mut self,
-        req_id: RequestId,
-        params: FoldingRangeParams,
-    ) -> ScheduledResult {
+    pub(crate) fn folding_range(&mut self, params: FoldingRangeParams) -> ScheduleResult {
         let path = as_path(params.text_document);
         let line_folding_only = self.const_config().doc_line_folding_only;
         self.implicit_focus_entry(|| Some(path.as_path().into()), 'f');
-        run_query!(req_id, self.FoldingRange(path, line_folding_only))
+        run_query!(self.FoldingRange(path, line_folding_only))
     }
 
-    pub(crate) fn selection_range(
-        &mut self,
-        req_id: RequestId,
-        params: SelectionRangeParams,
-    ) -> ScheduledResult {
+    pub(crate) fn selection_range(&mut self, params: SelectionRangeParams) -> ScheduleResult {
         let path = as_path(params.text_document);
         let positions = params.positions;
-        run_query!(req_id, self.SelectionRange(path, positions))
+        run_query!(self.SelectionRange(path, positions))
     }
 
-    pub(crate) fn document_highlight(
-        &mut self,
-        req_id: RequestId,
-        params: DocumentHighlightParams,
-    ) -> ScheduledResult {
+    pub(crate) fn document_highlight(&mut self, params: DocumentHighlightParams) -> ScheduleResult {
         let (path, position) = as_path_pos(params.text_document_position_params);
-        run_query!(req_id, self.DocumentHighlight(path, position))
+        run_query!(self.DocumentHighlight(path, position))
     }
 
-    pub(crate) fn document_symbol(
-        &mut self,
-        req_id: RequestId,
-        params: DocumentSymbolParams,
-    ) -> ScheduledResult {
+    pub(crate) fn document_symbol(&mut self, params: DocumentSymbolParams) -> ScheduleResult {
         let path = as_path(params.text_document);
-        run_query!(req_id, self.DocumentSymbol(path))
+        run_query!(self.DocumentSymbol(path))
     }
 
-    pub(crate) fn semantic_tokens_full(
-        &mut self,
-        req_id: RequestId,
-        params: SemanticTokensParams,
-    ) -> ScheduledResult {
+    pub(crate) fn semantic_tokens_full(&mut self, params: SemanticTokensParams) -> ScheduleResult {
         let path = as_path(params.text_document);
         self.implicit_focus_entry(|| Some(path.as_path().into()), 't');
-        run_query!(req_id, self.SemanticTokensFull(path))
+        run_query!(self.SemanticTokensFull(path))
     }
 
     pub(crate) fn semantic_tokens_full_delta(
         &mut self,
-        req_id: RequestId,
+
         params: SemanticTokensDeltaParams,
-    ) -> ScheduledResult {
+    ) -> ScheduleResult {
         let path = as_path(params.text_document);
         let previous_result_id = params.previous_result_id;
         self.implicit_focus_entry(|| Some(path.as_path().into()), 't');
-        run_query!(req_id, self.SemanticTokensDelta(path, previous_result_id))
+        run_query!(self.SemanticTokensDelta(path, previous_result_id))
     }
 
-    pub(crate) fn formatting(
-        &mut self,
-        req_id: RequestId,
-        params: DocumentFormattingParams,
-    ) -> ScheduledResult {
+    pub(crate) fn formatting(&mut self, params: DocumentFormattingParams) -> ScheduleResult {
         if matches!(self.config.formatter_mode, FormatterMode::Disable) {
-            return Ok(None);
+            return just_ok(serde_json::Value::Null);
         }
 
         let path: ImmutPath = as_path(params.text_document).as_path().into();
-        let source = self
-            .query_source(path, |source: typst::syntax::Source| Ok(source))
-            .map_err(|e| internal_error(format!("could not format document: {e}")))?;
-        self.client.schedule(req_id, self.formatter.run(source))
+        let source = self.query_source(path, |source: typst::syntax::Source| Ok(source))?;
+        erased_response(self.formatter.run(source))
     }
 
-    pub(crate) fn inlay_hint(
-        &mut self,
-        req_id: RequestId,
-        params: InlayHintParams,
-    ) -> ScheduledResult {
+    pub(crate) fn inlay_hint(&mut self, params: InlayHintParams) -> ScheduleResult {
         let path = as_path(params.text_document);
         let range = params.range;
-        run_query!(req_id, self.InlayHint(path, range))
+        run_query!(self.InlayHint(path, range))
     }
 
-    pub(crate) fn document_color(
-        &mut self,
-        req_id: RequestId,
-        params: DocumentColorParams,
-    ) -> ScheduledResult {
+    pub(crate) fn document_color(&mut self, params: DocumentColorParams) -> ScheduleResult {
         let path = as_path(params.text_document);
-        run_query!(req_id, self.DocumentColor(path))
+        run_query!(self.DocumentColor(path))
     }
 
-    pub(crate) fn document_link(
-        &mut self,
-        req_id: RequestId,
-        params: DocumentLinkParams,
-    ) -> ScheduledResult {
+    pub(crate) fn document_link(&mut self, params: DocumentLinkParams) -> ScheduleResult {
         let path = as_path(params.text_document);
-        run_query!(req_id, self.DocumentLink(path))
+        run_query!(self.DocumentLink(path))
     }
 
-    pub(crate) fn color_presentation(
-        &mut self,
-        req_id: RequestId,
-        params: ColorPresentationParams,
-    ) -> ScheduledResult {
+    pub(crate) fn color_presentation(&mut self, params: ColorPresentationParams) -> ScheduleResult {
         let path = as_path(params.text_document);
         let color = params.color;
         let range = params.range;
-        run_query!(req_id, self.ColorPresentation(path, color, range))
+        run_query!(self.ColorPresentation(path, color, range))
     }
 
-    pub(crate) fn code_action(
-        &mut self,
-        req_id: RequestId,
-        params: CodeActionParams,
-    ) -> ScheduledResult {
+    pub(crate) fn code_action(&mut self, params: CodeActionParams) -> ScheduleResult {
         let path = as_path(params.text_document);
         let range = params.range;
         let context = params.context;
-        run_query!(req_id, self.CodeAction(path, range, context))
+        run_query!(self.CodeAction(path, range, context))
     }
 
-    pub(crate) fn code_lens(
-        &mut self,
-        req_id: RequestId,
-        params: CodeLensParams,
-    ) -> ScheduledResult {
+    pub(crate) fn code_lens(&mut self, params: CodeLensParams) -> ScheduleResult {
         let path = as_path(params.text_document);
-        run_query!(req_id, self.CodeLens(path))
+        run_query!(self.CodeLens(path))
     }
 
-    pub(crate) fn completion(
-        &mut self,
-        req_id: RequestId,
-        params: CompletionParams,
-    ) -> ScheduledResult {
+    pub(crate) fn completion(&mut self, params: CompletionParams) -> ScheduleResult {
         let (path, position) = as_path_pos(params.text_document_position);
         let context = params.context.as_ref();
         let explicit =
@@ -234,58 +144,39 @@ impl ServerState {
             .and_then(|c| c.chars().next());
 
         self.implicit_position = Some(position);
-        run_query!(
-            req_id,
-            self.Completion(path, position, explicit, trigger_character)
-        )
+        run_query!(self.Completion(path, position, explicit, trigger_character))
     }
 
-    pub(crate) fn signature_help(
-        &mut self,
-        req_id: RequestId,
-        params: SignatureHelpParams,
-    ) -> ScheduledResult {
+    pub(crate) fn signature_help(&mut self, params: SignatureHelpParams) -> ScheduleResult {
         let (path, position) = as_path_pos(params.text_document_position_params);
 
         self.implicit_position = Some(position);
-        run_query!(req_id, self.SignatureHelp(path, position))
+        run_query!(self.SignatureHelp(path, position))
     }
 
-    pub(crate) fn rename(&mut self, req_id: RequestId, params: RenameParams) -> ScheduledResult {
+    pub(crate) fn rename(&mut self, params: RenameParams) -> ScheduleResult {
         let (path, position) = as_path_pos(params.text_document_position);
         let new_name = params.new_name;
-        run_query!(req_id, self.Rename(path, position, new_name))
+        run_query!(self.Rename(path, position, new_name))
     }
 
-    pub(crate) fn prepare_rename(
-        &mut self,
-        req_id: RequestId,
-        params: TextDocumentPositionParams,
-    ) -> ScheduledResult {
+    pub(crate) fn prepare_rename(&mut self, params: TextDocumentPositionParams) -> ScheduleResult {
         let (path, position) = as_path_pos(params);
-        run_query!(req_id, self.PrepareRename(path, position))
+        run_query!(self.PrepareRename(path, position))
     }
 
-    pub(crate) fn symbol(
-        &mut self,
-        req_id: RequestId,
-        params: WorkspaceSymbolParams,
-    ) -> ScheduledResult {
+    pub(crate) fn symbol(&mut self, params: WorkspaceSymbolParams) -> ScheduleResult {
         let pattern = (!params.query.is_empty()).then_some(params.query);
-        run_query!(req_id, self.Symbol(pattern))
+        run_query!(self.Symbol(pattern))
     }
 
-    pub(crate) fn on_enter(&mut self, req_id: RequestId, params: OnEnterParams) -> ScheduledResult {
+    pub(crate) fn on_enter(&mut self, params: OnEnterParams) -> ScheduleResult {
         let path = as_path(params.text_document);
         let range = params.range;
-        run_query!(req_id, self.OnEnter(path, range))
+        run_query!(self.OnEnter(path, range))
     }
 
-    pub(crate) fn will_rename_files(
-        &mut self,
-        req_id: RequestId,
-        params: RenameFilesParams,
-    ) -> ScheduledResult {
+    pub(crate) fn will_rename_files(&mut self, params: RenameFilesParams) -> ScheduleResult {
         log::info!("will rename files {params:?}");
         let paths = params
             .files
@@ -299,7 +190,7 @@ impl ServerState {
             .collect::<Option<Vec<_>>>()
             .ok_or_else(|| invalid_params("invalid urls"))?;
 
-        run_query!(req_id, self.WillRenameFiles(paths))
+        run_query!(self.WillRenameFiles(paths))
     }
 }
 
@@ -329,9 +220,7 @@ impl ServerState {
             #[cfg(feature = "export")]
             OnExport(req) => return self.on_export(req),
             #[cfg(not(feature = "export"))]
-            OnExport(_req) => {
-                return Err(tinymist_std::error_once!("export feature is not enabled"))
-            }
+            OnExport(_req) => return Err(internal_error("export feature is not enabled")),
             ServerInfo(_) => return self.collect_server_info(),
             // todo: query on dedicate projects
             _ => return self.query_on(query),
@@ -343,7 +232,9 @@ impl ServerState {
         type R = CompilerQueryResponse;
         assert!(query.fold_feature() != FoldRequestFeature::ContextFreeUnique);
 
-        let (mut snap, stat) = self.query_snapshot_with_stat(&query)?;
+        let (mut snap, stat) = self
+            .query_snapshot_with_stat(&query)
+            .map_err(internal_error)?;
         // todo: whether it is safe to inherit success_doc with changed entry
         if !self.is_pinning() {
             let input = query
@@ -377,7 +268,7 @@ impl ServerState {
                 }
             }
 
-            match query {
+            let res = match query {
                 SemanticTokensFull(req) => snap.run_semantic(req, R::SemanticTokensFull),
                 SemanticTokensDelta(req) => snap.run_semantic(req, R::SemanticTokensDelta),
                 InteractCodeContext(req) => snap.run_semantic(req, R::InteractCodeContext),
@@ -400,7 +291,9 @@ impl ServerState {
                 WorkspaceLabel(req) => snap.run_semantic(req, R::WorkspaceLabel),
                 DocumentMetrics(req) => snap.run_stateful(req, R::DocumentMetrics),
                 _ => unreachable!(),
-            }
+            };
+
+            res.map_err(internal_error)
         })
     }
 }
diff --git a/crates/tinymist/src/server.rs b/crates/tinymist/src/server.rs
index 320ad228..485ccc52 100644
--- a/crates/tinymist/src/server.rs
+++ b/crates/tinymist/src/server.rs
@@ -438,7 +438,7 @@ impl ServerState {
         let query_stats = self.project.analysis.report_query_stats();
         let alloc_stats = self.project.analysis.report_alloc_stats();
 
-        let snap = self.snapshot()?;
+        let snap = self.snapshot().map_err(internal_error)?;
         just_future(async move {
             let w = snap.world();
 
diff --git a/crates/tinymist/src/task/export.rs b/crates/tinymist/src/task/export.rs
index 2af72a63..11a3542b 100644
--- a/crates/tinymist/src/task/export.rs
+++ b/crates/tinymist/src/task/export.rs
@@ -8,7 +8,7 @@ use std::{ops::DerefMut, pin::Pin};
 
 use reflexo::ImmutPath;
 use reflexo_typst::{Bytes, CompilationTask, ExportComputation};
-use sync_ls::just_future;
+use sync_ls::{internal_error, just_future};
 use tinymist_project::LspWorld;
 use tinymist_query::OnExportRequest;
 use tinymist_std::error::prelude::*;
@@ -61,7 +61,7 @@ impl ServerState {
             }
         });
 
-        let snap = self.snapshot()?;
+        let snap = self.snapshot().map_err(internal_error)?;
         just_future(async move {
             let snap = snap.task(TaskInputs {
                 entry: Some(entry),
@@ -70,7 +70,9 @@ impl ServerState {
 
             let is_html = matches!(task, ProjectTask::ExportHtml { .. });
             let artifact = CompiledArtifact::from_graph(snap.clone(), is_html);
-            let res = ExportTask::do_export(task, artifact, lock_dir).await?;
+            let res = ExportTask::do_export(task, artifact, lock_dir)
+                .await
+                .map_err(internal_error)?;
             if let Some(update_dep) = update_dep {
                 tokio::spawn(update_dep(snap));
             }