Deprecate async-std-rt and document reqwless upgrade blocker

.github/workflows/build_and_lint.yml

@@ -34,7 +34,10 @@ jobs:
         run: cargo fmt --all -- --check
 
       - name: Clippy
-        run: cargo clippy --all-features -- -D warnings
+        # Exclude async-std-rt: it is deprecated (RUSTSEC-2025-0052) and emits a
+        # compile_error! at crate level, so --all-features would always fail.
+        # NOTE: When adding new Cargo features, add them to this list manually.
+        run: cargo clippy --features std,tokio-rt,embassy-rt,actix-rt,futures-rt,smol-rt,core,wallet,models,utils,helpers,json-rpc,websocket,cli -- -D warnings
 
       - name: Build (default)
         run: cargo build --release

CHANGELOG.md

@@ -18,6 +18,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [[v1.1.0]]
 
+- **`async-std-rt` feature deprecated**: The `async-std` crate has been officially discontinued (RUSTSEC-2025-0052). The `async-std-rt` feature now emits a `compile_error!` directing users to migrate to `smol-rt` as a drop-in replacement. Code using `async-std-rt` will no longer compile until the feature is updated.
+
+### Known Blockers
+
+- **`atomic-polyfill` advisory (RUSTSEC-2023-0089)**: Cannot be resolved yet. `reqwless` 0.13.0 pins `embedded-tls` 0.17.0 which transitively depends on `atomic-polyfill`. This is blocked upstream and will be resolved when `reqwless` upgrades its `embedded-tls` dependency.
+
 ### Added
 
 - Implemented full deserialization from hex binary back to JSON, update `definitions.json` to `xrpl.js` latest, added all codec test fixtures from xrpl.js and implemented tests for all of them.

Cargo.toml

@@ -81,6 +81,9 @@ embassy-time = { version = "0.3.2", optional = true }
 embedded-websocket-embedded-io = { version = "0.1.0", optional = true, default-features = false, features = [
     "embedded-io-async",
 ] }
+# NOTE: reqwless 0.13.0 pins embedded-tls 0.17.0 which depends on atomic-polyfill
+# (RUSTSEC-2023-0089). Newer embedded-tls versions use portable-atomic instead, but
+# reqwless has not released a compatible update yet. Blocked upstream.
 reqwless = { version = "0.13.0", optional = true }
 reqwest = { version = "0.12.7", optional = true, features = ["json"] }
 tokio-tungstenite = { version = "0.24.0", optional = true, features = [
@@ -89,6 +92,8 @@ tokio-tungstenite = { version = "0.24.0", optional = true, features = [
 embassy-futures = { version = "0.1.1" }
 embedded-nal-async = { version = "0.8.0", optional = true }
 actix-rt = { version = "2.10.0", optional = true }
+# DEPRECATED: async-std has been discontinued (RUSTSEC-2025-0052). Use smol-rt instead.
+# Retained so the async-std-rt feature gate resolves; enabling it emits a compile_error.
 async-std = { version = "1.13.0", optional = true }
 futures-executor = { version = "0.3.30", optional = true }
 futures-timer = { version = "3.0.3", optional = true }

src/asynch/clients/exceptions.rs

@@ -1,4 +1,4 @@
-#[cfg(not(feature = "std"))]
+#[cfg(all(not(feature = "std"), feature = "websocket"))]
 use alloc::boxed::Box;
 use thiserror_no_std::Error;
 

src/asynch/mod.rs

@@ -11,6 +11,16 @@ pub mod transaction;
 #[cfg(feature = "helpers")]
 pub mod wallet;
 
+// async-std has been discontinued (RUSTSEC-2025-0052). Emit a compile-time error so
+// callers get a clear message instead of a runtime panic, and avoid unreachable-code
+// lint when --all-features is used alongside other runtime feature flags.
+#[cfg(feature = "async-std-rt")]
+compile_error!(
+    "The async-std-rt feature is deprecated and no longer supported. \
+     async-std has been discontinued (RUSTSEC-2025-0052). \
+     Use the smol-rt feature instead."
+);
+
 async fn wait_seconds(_seconds: u64) {
     #[cfg(feature = "tokio-rt")]
     {
@@ -25,11 +35,6 @@ async fn wait_seconds(_seconds: u64) {
         use core::time::Duration;
         actix_rt::time::sleep(Duration::from_secs(_seconds)).await;
     }
-    #[cfg(feature = "async-std-rt")]
-    {
-        use core::time::Duration;
-        async_std::task::sleep(Duration::from_secs(_seconds)).await;
-    }
     #[cfg(feature = "futures-rt")]
     {
         use core::time::Duration;