chore: switch to stable toolchain

Cargo.toml

@@ -89,6 +89,7 @@ tower-http = { version = "0.6.8", features = ["trace"] }
 tracing = { version = "0.1.44", features = ["release_max_level_debug"] }
 tracing-futures = { version = "0.2.5", features = ["futures-03"] }
 tracing-subscriber = { version = "0.3.20", features = ["env-filter", "fmt"] }
+trait-set = "0.3.0"
 uuid = { version = "1.22.0", features = ["v4"] }
 validator = { version = "0.20.0", features = ["derive"] }
 vllm-chat = { path = "src/chat" }

rust-toolchain.toml

@@ -1,2 +1,2 @@
 [toolchain]
-channel = "nightly-2026-03-10"
+channel = "1.95"

rustfmt.toml

@@ -1,11 +1 @@
-unstable_features = true
 style_edition = "2024"
-comment_width = 100
-format_code_in_doc_comments = true
-format_macro_matchers = true
-normalize_comments = true
-normalize_doc_attributes = true
-imports_granularity = "Module"
-group_imports = "StdExternalCrate"
-reorder_impl_items = true
-wrap_comments = true

rustfmt.unstable.toml

@@ -0,0 +1,15 @@
+# Optional local formatting profile. CI and pre-commit use rustfmt.toml.
+# Apply manually with:
+#   cargo +nightly fmt -- --config-path rustfmt.unstable.toml
+
+unstable_features = true
+style_edition = "2024"
+comment_width = 100
+format_code_in_doc_comments = true
+format_macro_matchers = true
+normalize_comments = true
+normalize_doc_attributes = true
+imports_granularity = "Module"
+group_imports = "StdExternalCrate"
+reorder_impl_items = true
+wrap_comments = true

src/chat/Cargo.toml

@@ -24,6 +24,7 @@ thiserror.workspace = true
 thiserror-ext.workspace = true
 tool-parser.workspace = true
 tracing.workspace = true
+trait-set.workspace = true
 uuid.workspace = true
 vllm-engine-core-client.workspace = true
 vllm-llm.workspace = true

src/chat/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(trait_alias)]
-
 //! Minimal chat facade above [`vllm_text`].
 //!
 //! This crate keeps the northbound boundary intentionally small:

src/chat/src/output/default/mod.rs

@@ -7,6 +7,7 @@ use std::sync::Once;
 
 use futures::{Stream, StreamExt as _};
 use tracing::info;
+use trait_set::trait_set;
 use vllm_text::tokenizer::DynTokenizer;
 
 use self::reasoning::reasoning_event_stream;
@@ -23,7 +24,9 @@ use crate::parser::tool::{ToolParser, ToolParserFactory};
 use crate::request::{ChatRequest, ChatToolChoice};
 use crate::{Error, Result as ChatResult};
 
-trait ContentEventStream = Stream<Item = Result<ContentEvent>> + Send + 'static;
+trait_set! {
+    trait ContentEventStream = Stream<Item = Result<ContentEvent>> + Send + 'static;
+}
 
 /// Default request-scoped output processor used by Hugging Face style chat backends.
 ///

src/chat/src/output/mod.rs

@@ -3,6 +3,7 @@ use std::sync::Arc;
 
 use futures::Stream;
 use subenum::subenum;
+use trait_set::trait_set;
 use uuid::Uuid;
 use vllm_text::output::{DecodedLogprobs, DecodedPromptLogprobs, DecodedTextEvent};
 
@@ -114,12 +115,14 @@ pub trait ChatOutputProcessor: Send {
 /// Trait-object form of [`ChatOutputProcessor`].
 pub type DynChatOutputProcessor = Box<dyn ChatOutputProcessor>;
 
-/// Boxed-stream constraint for decoded text updates.
-pub(crate) trait DecodedTextEventStream = Stream<Item = Result<DecodedTextEvent>> + Send + 'static;
-/// Boxed-stream constraint for internal assistant events.
-pub(crate) trait AssistantEventStream = Stream<Item = Result<AssistantEvent>> + Send + 'static;
-/// Boxed-stream constraint for public chat events.
-pub(crate) trait ChatEventStream = Stream<Item = Result<ChatEvent>> + Send + 'static;
+trait_set! {
+    /// Boxed-stream constraint for decoded text updates.
+    pub(crate) trait DecodedTextEventStream = Stream<Item = Result<DecodedTextEvent>> + Send + 'static;
+    /// Boxed-stream constraint for internal assistant events.
+    pub(crate) trait AssistantEventStream = Stream<Item = Result<AssistantEvent>> + Send + 'static;
+    /// Boxed-stream constraint for public chat events.
+    pub(crate) trait ChatEventStream = Stream<Item = Result<ChatEvent>> + Send + 'static;
+}
 
 /// Generate the northbound tool-call ID using the OpenAI-style `call_<id>` format.
 // TODO: support other ID scheme like Kimi-K2's `functions.{name}:{global_index}`.

src/chat/src/stream.rs

@@ -3,6 +3,7 @@ use std::sync::Arc;
 use std::task::{Context, Poll};
 
 use futures::Stream;
+use trait_set::trait_set;
 use vllm_text::{DecodedLogprobs, DecodedPositionLogprobs, DecodedPromptLogprobs};
 
 use crate::FinishReason;
@@ -118,7 +119,9 @@ impl Stream for ChatEventStream {
     }
 }
 
-pub trait ChatEventStreamTrait = Stream<Item = Result<ChatEvent>> + Send + 'static;
+trait_set! {
+    pub trait ChatEventStreamTrait = Stream<Item = Result<ChatEvent>> + Send + 'static;
+}
 
 #[cfg(test)]
 mod tests {

src/engine-core-client/Cargo.toml

@@ -13,6 +13,7 @@ bytes.workspace = true
 enum-as-inner.workspace = true
 futures.workspace = true
 hex.workspace = true
+itertools.workspace = true
 parking_lot.workspace = true
 rmp-serde.workspace = true
 rmpv.workspace = true

src/engine-core-client/src/client.rs

@@ -434,7 +434,7 @@ impl EngineCoreClient {
             .inner
             .register_request(request_id.clone(), data_parallel_rank)?;
 
-        let result = try {
+        let result: Result<()> = async {
             if let Some(coordinator) = self.coordinator.as_ref() {
                 let snapshot = coordinator.snapshot();
                 req.current_wave = snapshot.current_wave;
@@ -452,7 +452,9 @@ impl EngineCoreClient {
             self.inner
                 .send_to_engine(&engine_id, EngineCoreRequestType::Add, &req)
                 .await?;
-        };
+            Ok(())
+        }
+        .await;
 
         // Failed to send the request to the engine, roll back the registration.
         if let Err(error) = result {

src/engine-core-client/src/client/imp.rs

@@ -272,7 +272,7 @@ pub(crate) async fn run_output_dispatcher_loop(
     inner: Arc<ClientInner>,
     mut output_rx: mpsc::Receiver<Result<EngineCoreOutputs>>,
 ) {
-    let Err(error) = try {
+    let result: Result<()> = async {
         loop {
             let outputs = match output_rx.recv().await {
                 Some(outputs) => outputs,
@@ -350,7 +350,9 @@ pub(crate) async fn run_output_dispatcher_loop(
                 }
             }
         }
-    };
+    }
+    .await;
+    let Err(error) = result else { return };
 
     warn!(error = %error.as_report(), "output dispatcher exiting with error");
     inner.close_registries(Arc::new(error));

src/engine-core-client/src/coordinator/external.rs

@@ -133,14 +133,14 @@ impl ExternalCoordinatorService {
     /// Drive the coordinator event loop until either side of the control plane
     /// is closed or a fatal error is observed.
     pub(crate) async fn run(mut self, inner: Arc<ClientInner>) {
-        let Err(error) = try {
+        let result: Result<()> = async {
             loop {
                 tokio::select! {
                     // Received frontend-originated command from the handle.
                     command = self.command_rx.recv() => {
                         let Some(command) = command else {
                             warn!("external coordinator command channel closed, shutting down service");
-                            return;
+                            return Ok(());
                         };
                         self.handle_command(command).await?;
                     }
@@ -151,7 +151,9 @@ impl ExternalCoordinatorService {
                     }
                 }
             }
-        };
+        }
+        .await;
+        let Err(error) = result else { return };
 
         warn!(
             error = %error.as_report(),

src/engine-core-client/src/coordinator/inproc.rs

@@ -170,28 +170,30 @@ impl InProcCoordinatorRunner {
         mut output_rx: mpsc::Receiver<Result<EngineCoreOutputs>>,
         inner: Arc<ClientInner>,
     ) {
-        let Err(error) = try {
+        let result: Result<()> = async {
             loop {
                 tokio::select! {
                     // Received frontend-originated command from the handle.
                     command = self.command_rx.recv() => {
                         let Some(command) = command else {
                             warn!("coordinator command channel closed, shutting down coordinator runner");
-                            return;
+                            return Ok(());
                         };
                         self.handle_command(command).await?;
                     }
                     // Received engine-originated control output from the coordinator socket.
                     outputs = output_rx.recv() => {
                         let Some(outputs) = outputs else {
                             warn!("coordinator output channel closed, shutting down coordinator runner");
-                            return;
+                            return Ok(());
                         };
                         self.handle_outputs(outputs?).await?;
                     }
                 }
             }
-        };
+        }
+        .await;
+        let Err(error) = result else { return };
 
         warn!(error = %error.as_report(), "coordinator runner exiting with error");
         inner.close_registries(Arc::new(error));

src/engine-core-client/src/lib.rs

@@ -1,6 +1,3 @@
-#![feature(iterator_try_collect)]
-#![feature(try_blocks)]
-
 mod client;
 mod coordinator;
 mod error;

src/engine-core-client/src/protocol/logprobs/array.rs

@@ -1,6 +1,7 @@
 use std::io::Cursor;
 
 use byteorder::{BigEndian, LittleEndian, NativeEndian, ReadBytesExt};
+use itertools::Itertools as _;
 
 use crate::error::{Error, Result, ext_value_decode};
 use crate::protocol::logprobs::wire::{WireArrayData, WireNdArray};

src/server/Cargo.toml

@@ -9,6 +9,7 @@ asynk-strim-attr.workspace = true
 axum.workspace = true
 futures.workspace = true
 http-body.workspace = true
+itertools.workspace = true
 libc.workspace = true
 prost.workspace = true
 prost-types.workspace = true

src/server/src/lib.rs

@@ -1,5 +1,3 @@
-#![feature(iterator_try_collect)]
-
 //! Minimal OpenAI-compatible HTTP server above [`vllm_chat`].
 
 mod config;

src/server/src/routes/openai/chat_completions/convert.rs

@@ -1,3 +1,4 @@
+use itertools::Itertools as _;
 use vllm_chat::{
     AssistantContentBlock, AssistantToolCall, ChatContent, ChatContentPart,
     ChatMessage as VllmChatMessage, ChatOptions, ChatRequest, ChatTool, ChatToolChoice,
@@ -49,11 +50,11 @@ pub(crate) fn prepare_chat_request(
         .echo
         .then(|| extract_last_assistant_content(&request.messages))
         .flatten();
-    let messages = request
+    let messages: Vec<_> = request
         .messages
         .into_iter()
         .map(convert_message)
-        .try_collect::<Vec<_>>()?;
+        .try_collect()?;
     let generation_prompt_mode = normalize_generation_prompt_mode(
         request.add_generation_prompt,
         request.continue_final_message,

src/server/src/routes/openai/completions.rs

@@ -431,6 +431,7 @@ fn done_sse_event() -> Event {
 #[cfg(test)]
 mod tests {
     use futures::{StreamExt as _, stream};
+    use itertools::Itertools as _;
     use vllm_text::{
         DecodedLogprobs, DecodedPositionLogprobs, DecodedTextEvent, DecodedTokenLogprob,
         FinishReason, Finished,
@@ -540,9 +541,9 @@ mod tests {
         .collect::<Vec<_>>()
         .await;
 
-        let chunks = chunks
+        let chunks: Vec<_> = chunks
             .into_iter()
-            .try_collect::<Vec<_>>()
+            .try_collect()
             .expect("stream should succeed");
 
         match &chunks[0] {

src/server/src/routes/openai/utils/logprobs.rs

@@ -1,5 +1,6 @@
 use std::collections::HashMap;
 
+use itertools::Itertools as _;
 use vllm_text::{
     CollectedTextOutput, DecodedLogprobs, DecodedPositionLogprobs, DecodedPromptLogprobs,
     DecodedTokenLogprob,

src/text/Cargo.toml

@@ -12,6 +12,7 @@ enum-as-inner.workspace = true
 fastokens.workspace = true
 futures.workspace = true
 hf-hub.workspace = true
+itertools.workspace = true
 rustc-hash.workspace = true
 serde.workspace = true
 serde_json.workspace = true
@@ -22,6 +23,7 @@ thiserror-ext.workspace = true
 tiktoken-rs.workspace = true
 tokenizers.workspace = true
 tracing.workspace = true
+trait-set.workspace = true
 vllm-engine-core-client.workspace = true
 vllm-llm.workspace = true
 

src/text/src/lib.rs

@@ -1,6 +1,3 @@
-#![feature(trait_alias)]
-#![feature(iterator_try_collect)]
-
 //! Shared text-generation support used by chat and future raw completions.
 //!
 //! This crate intentionally stays below chat semantics:
@@ -20,6 +17,7 @@ pub use output::{
     DecodedTextEvent, DecodedTokenLogprob, Finished, TextDecodeOptions, TextOutputStreamExt,
 };
 pub use request::{Prompt, SamplingParams, TextRequest};
+use trait_set::trait_set;
 use vllm_engine_core_client::EngineCoreClient;
 pub use vllm_llm::FinishReason;
 use vllm_llm::{GenerateOutputStream, Llm};
@@ -34,8 +32,10 @@ pub mod output;
 mod request;
 pub mod tokenizer;
 
-/// Shared streamed text output type used by raw completions and other text-only northbound paths.
-pub trait TextOutputStream = Stream<Item = Result<DecodedTextEvent>> + Send + 'static;
+trait_set! {
+    /// Shared streamed text output type used by raw completions and other text-only northbound paths.
+    pub trait TextOutputStream = Stream<Item = Result<DecodedTextEvent>> + Send + 'static;
+}
 
 /// Raw text facade above [`Llm`].
 ///

src/text/src/output/logprobs.rs

@@ -1,3 +1,4 @@
+use itertools::Itertools as _;
 use serde::{Deserialize, Serialize};
 use vllm_llm::{Logprobs, PositionLogprobs};