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rust-doctor · Framework

`axum-handler-not-async`

Flags non-async handler functions in axum. Web framework handlers run on the async runtime and must not block.

Severity: warning
Confidence: medium
Analyzer: syn-ast
Default policy: Enabled

Tags

framework
heuristic

Framework requirements

axum >=0.7,<0.9

Limitations

Syntactic analysis does not have rustc name resolution or inferred type information.

Remediation

Make the handler `async fn` and use async I/O operations.

Fix capability: guidance