AWS Lambda Durable Functions began supporting custom Durable Execution SDKs, enabling developers to implement durable workflows in any runtime compatible with Lambda, including those not previously supported by managed SDKs. This change overcomes prior limitations tied to Node.js, Python, Java, and C#/.NET SDK availability by allowing packaging of custom runtimes on Amazon Linux 2023.
To ensure SDK correctness, AWS released open-source Durable Execution Conformance Tests that validate custom SDK behavior through automated deployment, invocation, and execution history validation. This enhanced flexibility facilitates long-running, fault-tolerant workflows with one-year execution limits without additional infrastructure management, available across AWS Regions supporting Durable Functions.
Source & further reading
AWS Lambda durable functions now supports custom Durable Execution SDK ↗Source published 2026-07-28. This report was prepared with AI assistance from the linked primary-source material. Claims and limitations should be checked against the original announcement or research.