v1.1.1

Thank you to all the contributors who helped make this release possible. We appreciate your time, effort, and passion for the Rust Lambda community. ❤️

Lambda Managed Instances

The runtime now supports Lambda Managed Instances via the concurrency-tokio feature flag (previously experimental-concurrency). Lambda Managed Instances allow multiple concurrent requests to be processed within a single execution environment. When AWS_LAMBDA_MAX_CONCURRENCY is set, the runtime spawns multiple independent long-poll workers to handle concurrent invocations. If the env var is unset or <= 1, it falls back to sequential behavior automatically. This lets you use the same handler for both classic Lambda and Lambda Managed Instances. (#1067)

[dependencies]
lambda_runtime = { version = "1.1", features = ["concurrency-tokio"] }

lambda_runtime::run_concurrent(service_fn(my_handler)).await?;

For a complete working example, see examples/basic-lambda-concurrent. For detailed guidance on building functions for multi-concurrency, including shared state patterns and database connection pools, see the Rust runtime for Lambda Managed Instances documentation.

We would like also to involve the community in a broader discussion about improving our approach on multiconcurrency. You can find the discussion in (#1120)

lambda_runtime - 1.1.1

Added

• (lambda-managed-instances) log non-2xx Lambda Runtime API responses with status and body (#1109)
• tenant ID propagation for multi-tenant Lambda use cases. The tenant_id is available in the context.tenant_id field (Option<String>) and is automatically extracted from the lambda-runtime-aws-tenant-id header when present (#1082)
• Add builder pattern support for event response types (#1090)

Fixed

• (test) fix test_concurrent_structured_logging_isolation (#1121)

Changed

• MSRV updated from 1.82.0 to 1.84.0, enabled MSRV-aware resolver (#1078)
• X-Ray trace ID now sourced from Context instead of environment variables (#1067)

Other

• (lambda-managed-instances) add tokio_unstable to known cfgs to avoid linter warns (#1095)
• (lambda-managed-instances) verify request-ID isolation in concurrent exec (#1086)
• (lambda-managed-instances) warn on run() with AWS_LAMBDA_MAX_CONCURRENCY, rename feature experimental-concurrency to concurrency-tokio (#1095)
• Introducing Harness Testing (#1103)

1.1.0-rc1 - 2026-02-04

Added

• (lambda-managed-instances) Lambda Managed Instances support via concurrency-tokio feature flag (#1067)
• (lambda-managed-instances) tenant ID propagation for multi-tenant Lambda use cases (#1082)

Changed

• MSRV updated from 1.82.0 to 1.84.0, enabled MSRV-aware resolver (#1078)
• X-Ray trace ID now sourced from Context instead of environment variables (#1067)

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lambda_http - 1.1.1

Added

• (lambda-managed-instances) Lambda Managed Instances support via concurrency-tokio feature flag with run_concurrent() and BoxCloneService for concurrent streaming responses (#1067)
• Add builder pattern support for event response types (#1090)

Changed

• MSRV updated from 1.82.0 to 1.84.0, enabled MSRV-aware resolver (#1078)

Other

• (lambda-managed-instances) add tokio_unstable to known cfgs to avoid linter warns (#1095)
• (lambda-managed-instances) warn on run() with AWS_LAMBDA_MAX_CONCURRENCY, rename feature experimental-concurrency to concurrency-tokio (#1095)
• (lambda-managed-instances) verify request-ID isolation in concurrent exec (#1086)
• Introducing Harness Testing (#1103)
• disable default features of lambda-runtime (#1093)

1.1.0-rc1 - 2026-02-04

Added

• (lambda-managed-instances) Lambda Managed Instances support via concurrency-tokio feature flag with run_concurrent() and BoxCloneService for concurrent streaming responses (#1067)

Changed

• MSRV updated from 1.82.0 to 1.84.0, enabled MSRV-aware resolver (#1078)

---

lambda_runtime_api_client - 1.0.2

Added

• (lambda-managed-instances) API client connection pooling for concurrent requests (#1067)

Changed

• MSRV updated from 1.82.0 to 1.84.0, enabled MSRV-aware resolver (#1078)

---

lambda-extension - 1.0.3

Added

• Make Telemetry API log record type generic (#1098)

1.0.2 - 2026-01-06

Changed

• MSRV updated from 1.82.0 to 1.84.0, enabled MSRV-aware resolver (#1078)

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aws_lambda_events - 1.1.1

Added

• (all types) Add builder pattern support for event response types (#1090)
• (IoT) support X509 custom authorizer in IoT events (#1114)
• (control tower) add Control Tower lifecycle events module (#1107)
• (sns) support SubscriptionConfirmation and UnsubscribeConfirmation message types (#1102)
• (vpc lattice) add VPC Lattice event structures (#1036)
• (sqs, kinesis) Improve ergonomics of SqsBatchResponse and KinesisEventResponse (#1063)

Fixed

• (cognito) claims_to_add_or_override type in CognitoEventUserPoolsPreTokenGenV2 (#1100)

Other

• (api gateway) deprecate authorizer-specific fields in ApiGatewayV2httpRequest (#1089)

1.0.3 - 2026-01-06

Changed

• MSRV updated from 1.82.0 to 1.84.0, enabled MSRV-aware resolver (#1078)

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Contributors

@alessandrobologna, @jlizen, @FullyTyped, @dap0am, @nstilt1, @raphael-theriault-swi, @abhu85, @flobz, @salmanmkc, @darklight3it, @lmammino, @andrew, @abhigya, @MartinMadsen, @HaroldSun