Add WaitForConditionAsync polling primitive (DOTNET-8665) by GarrettBeatty · Pull Request #2376 · aws/aws-lambda-dotnet

GarrettBeatty · 2026-05-14T21:41:52Z

What

Adds service-mediated polling to Amazon.Lambda.DurableExecution. WaitForConditionAsync repeatedly evaluates a check function with a configurable wait strategy between attempts; each iteration runs in its own Lambda invocation (suspended via STEP + RETRY checkpoints carrying NextAttemptDelaySeconds), so polling does not consume compute time while waiting between checks.

Public API:

Type	Purpose
`IDurableContext.WaitForConditionAsync<TState>(...)`	Poll until the user-supplied predicate signals done or `maxAttempts` is exhausted. Per-iteration state is serialized via the `ILambdaSerializer` registered on `ILambdaContext.Serializer` (same pattern as `StepAsync` / `RunInChildContextAsync`).
`IConditionCheckContext`	Passed to the check func: `Logger`, `AttemptNumber`.
`WaitForConditionConfig<TState>`	Required `InitialState` + `WaitStrategy`.
`IWaitStrategy<TState>`	`Decide(state, attempt)` returning `WaitDecision`.
`WaitDecision`	Readonly record struct: `ShouldContinue`, `Delay`, factories `Stop()` / `ContinueAfter(TimeSpan)`.
`WaitStrategy` factories	`Exponential`, `Linear`, `Fixed`, `FromDelegate` — each accepting an optional `Func<TState, bool> isDone` predicate.
`WaitForConditionException`	Thrown when `maxAttempts` is exhausted; carries `AttemptsExhausted` and `LastState` (preserved across both live execution and replay).

How

Internal/WaitForConditionOperation<TState> runs as a STEP with SubType = "WaitForCondition":

Each iteration calls the user check function with the current state. The strategy's Decide(state, attempt) returns either Stop() (success — return state) or ContinueAfter(delay) (suspend until next attempt). Continuing emits Action=RETRY with the new state in the payload and NextAttemptDelaySeconds set so the durable execution service schedules the next invocation without consuming compute time.
Strategies signal max-attempts exhausted by throwing WaitForConditionException directly from Decide(); the operation enriches with LastState before checkpointing FAIL. LastState survives FAIL replay: serialized into the FAIL payload at write time and deserialized in BuildFailureException with a warning-logged fallback for legacy / corrupt data.
Serialization is delegated to the registered ILambdaSerializer via stream-based Serialize<T> / Deserialize<T> calls — no AOT trim attributes on the public API. Mirrors StepOperation / ChildContextOperation.
ExponentialBackoff helper is extracted for sharing between this operation and ExponentialRetryStrategy. Math is byte-for-byte identical to the existing implementation.
Reuses OperationSubTypes.WaitForCondition from Wave 0 (doc updates #2372).

Defaults: 60 attempts, 5s initial delay, 300s max delay, 1.5x rate, Full jitter — distinct from RetryStrategy.Default and matching Python/JS/Java reference SDKs.

Cross-SDK note: Python returns success on max-attempts exhausted; .NET / Java / JS throw. Workflows ported from Python should review for new failure modes. Documented in the design doc.

Stacked on top of #2372.

Fixes DOTNET-8665.

Testing

41 new unit tests covering each wait strategy, the isDone predicate paths, max-attempts exhaustion, user-check exceptions, replay determinism, exponential-backoff bounds, and corrupt-payload fallback logging:

Each WaitStrategy factory: Exponential, Linear, Fixed, FromDelegate — both with and without isDone predicate.
WaitForConditionException thrown after max-attempts; AttemptsExhausted + LastState populated.
Replay determinism: SUCCEEDED returns cached state, FAILED reconstructs WaitForConditionException with LastState, STARTED re-suspends.
LastState survives FAIL replay; corrupt FAIL payload falls back gracefully with a warning.
ExponentialBackoff shared math: byte-for-byte identical to ExponentialRetryStrategy (regression test).
User check function throws are surfaced with the original exception preserved.

5 new integration tests build successfully (require AWS credentials to run).

Build clean: 0 warnings, 0 errors on net8.0 and net10.0.

Out of scope (follow-up PRs)

MapAsync / continued parallel-suite work.
DurableLogger replay-suppression (currently NullLogger).
Annotations source-generator integration / [DurableExecution] attribute.
DurableTestRunner / Amazon.Lambda.DurableExecution.Testing package.
dotnet new lambda.DurableFunction blueprint.

stack-info: PR: #2361, branch: GarrettBeatty/stack/3

Implements the minimum viable slice of the Amazon.Lambda.DurableExecution SDK: a workflow can run StepAsync and WaitAsync against a real Lambda, with replay-aware checkpointing wired through to the AWS service. Public API surface introduced: - DurableFunction.WrapAsync — entry point that handles the durable execution envelope (input hydration, output construction, status mapping) - IDurableContext.StepAsync / WaitAsync (4 Step overloads, 1 Wait) - StepConfig with serializer hook (retry deferred to follow-up PR) - ICheckpointSerializer interface - [DurableExecution] attribute (recognized by future source generator) - DurableExecutionException base + StepException Internals: - DurableExecutionHandler — Task.WhenAny race between user code and the suspension signal, returning Succeeded/Failed/Pending - ExecutionState — replay-aware operation lookup and pending checkpoint buffer - OperationIdGenerator — deterministic, replay-stable IDs - TerminationManager — TaskCompletionSource-based suspension trigger - LambdaDurableServiceClient — wraps AWSSDK.Lambda's checkpoint and state APIs Tests: - 86 unit tests covering enums, exceptions, models, configs, ID generation, termination, execution state, the handler race, the context (Step + Wait paths), and the WrapAsync entry point - 8 end-to-end integration tests deploying real Lambdas via Docker on the provided.al2023 runtime: StepWaitStep, MultipleSteps, WaitOnly, LongerWait, ReplayDeterminism, RetrySucceeds, RetryExhausts, StepFails Out of scope (follow-up PRs): - IRetryStrategy, ExponentialRetryStrategy, retry decision factories - DefaultJsonCheckpointSerializer - DurableLogger replay-suppression (currently returns NullLogger) - Callbacks, InvokeAsync, ParallelAsync, MapAsync, RunInChildContextAsync, WaitForConditionAsync — interface intentionally does not declare them - Annotations source-generator integration - DurableTestRunner / Amazon.Lambda.DurableExecution.Testing package - dotnet new lambda.DurableFunction blueprint stack-info: PR: #2360, branch: GarrettBeatty/stack/2 remove update update update update

Match the Python / Java / JavaScript reference SDKs' replay-mode model: the workflow is "replaying" iff it has not yet revisited every checkpointed completed user-replayable operation. A single global flag flipped on the first fresh op (the prior model) misclassified workflow- body code that runs before the first step and would not generalize to Map/Parallel/Callback later. ExecutionState changes: - Replace `Mode`/`ExecutionMode`/`EnterExecutionMode()` with `IsReplaying` + `TrackReplay(operationId)`. - Initial replay decision: any non-EXECUTION op present means we're replaying. The service always sends an EXECUTION-type op carrying the input payload — that's bookkeeping, not user history, so it does not count toward replay (matches Python execution.py:258, Java ExecutionManager:81, JS execution-context.ts:62). - TrackReplay flips IsReplaying false once every checkpointed terminal- status non-EXECUTION op has been visited. Terminal set matches Python's: SUCCEEDED, FAILED, CANCELLED, STOPPED. Operation changes: - DurableOperation.ExecuteAsync calls TrackReplay(OperationId) at the top, so every operation participates in visit accounting without each subclass needing to remember. - StepOperation/WaitOperation drop their manual EnterExecutionMode calls. Tests: - ExecutionStateTests rewritten around IsReplaying/TrackReplay, including pinning regressions: only-EXECUTION-op ⇒ NotReplaying, all-visited ⇒ flips out of replay, PENDING ops do not block transition, idempotency. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

stack-info: PR: #2363, branch: GarrettBeatty/stack/3

+
+COPY bin/publish/ ${LAMBDA_TASK_ROOT}
+
+ENTRYPOINT ["/var/task/bootstrap"]


+
+COPY bin/publish/ ${LAMBDA_TASK_ROOT}
+
+ENTRYPOINT ["/var/task/bootstrap"]


+
+COPY bin/publish/ ${LAMBDA_TASK_ROOT}
+
+ENTRYPOINT ["/var/task/bootstrap"]


+
+COPY bin/publish/ ${LAMBDA_TASK_ROOT}
+
+ENTRYPOINT ["/var/task/bootstrap"]


+
+COPY bin/publish/ ${LAMBDA_TASK_ROOT}
+
+ENTRYPOINT ["/var/task/bootstrap"]


Adds child-context support to the .NET Durable Execution SDK. A child context is a logical sub-workflow with its own deterministic operation-ID space, persisted as a CONTEXT operation so subsequent invocations replay the cached value without re-executing the function. Public surface: - IDurableContext.RunInChildContextAsync<T> (reflection + AOT-safe ICheckpointSerializer<T> overloads, plus a void overload). - ChildContextConfig with SubType (observability label) and ErrorMapping (transform exceptions before they surface to the caller). - ChildContextException for failure surfacing. Used as a building block for upcoming WaitForCallbackAsync. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Lays down shared types/constants for the upcoming durable-execution context operations (Callbacks, Invoke, Parallel, Map, WaitForCondition) and updates the design doc to match decisions reached after comparing against the Python, JS, and Java reference SDKs. SDK changes: - OperationSubTypes constants class (Step, Wait, Callback, WaitForCallback, Invoke, WaitForCondition, Parallel, ParallelBranch, Map, MapIteration). Replaces hard-coded SubType literals in StepOperation and WaitOperation. - OperationStatuses.TimedOut for callback/invoke timeout handling. Design-doc alignment: - Drop Serializer field from CallbackConfig, InvokeConfig, ChildContextConfig. Custom serializers flow through AOT-safe ICheckpointSerializer<T> overloads (matches the existing StepConfig pattern documented at line 1247). - InvokeConfig gains TenantId (matches Python/JS/Java); drops PayloadSerializer / ResultSerializer. - BatchItemStatus.Cancelled -> Started. The SDK does not synchronously cancel branches; the wire state of items still in flight when the batch resolves (e.g., FirstSuccessful short-circuit) is STARTED. Matches Python and JS. - IBatchResult<T> expanded to the full JS/Python surface: adds Started, GetErrors(), HasFailure, SuccessCount, FailureCount, StartedCount, TotalCount. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Adds service-mediated polling to the .NET Durable Execution SDK. WaitForConditionAsync repeatedly evaluates a check function with configurable wait strategy between attempts; each iteration is its own Lambda invocation (suspended via STEP+RETRY checkpoints carrying NextAttemptDelaySeconds), so polling does not consume compute time. Public surface: - IDurableContext.WaitForConditionAsync<TState> (reflection + AOT-safe overloads taking ICheckpointSerializer<TState>) - IConditionCheckContext (Logger + AttemptNumber) - WaitForConditionConfig<TState> (required InitialState + WaitStrategy) - IWaitStrategy<TState> with Decide(state, attempt) returning WaitDecision - WaitDecision (readonly record struct, ShouldContinue + Delay, Stop() / ContinueAfter(TimeSpan) factories) - WaitStrategy factories: Exponential / Linear / Fixed / FromDelegate, each accepting an optional Func<TState, bool> isDone predicate - WaitForConditionException with AttemptsExhausted and LastState (preserved across both live execution and replay) Internal: - WaitForConditionOperation<TState> wire format = STEP + SubType "WaitForCondition". Each polling iteration emits Action=RETRY with the new state in payload and NextAttemptDelaySeconds for the service to schedule the next invocation. - Strategies signal max-attempts exhausted by throwing WaitForConditionException directly from Decide(); the operation enriches with LastState before checkpointing FAIL. - LastState survives FAIL replay: serialized into FAIL payload at write time, deserialized in BuildFailureException with warning-logged fallback for legacy/corrupt data. - ExponentialBackoff helper extracted for sharing with ExponentialRetryStrategy. Math is byte-for-byte identical. - Reuses OperationSubTypes.WaitForCondition from Wave 0. Defaults: 60 attempts / 5s initial / 300s max / 1.5x rate / Full jitter - distinct from RetryStrategy.Default and matching Python/JS/Java reference SDKs. (Note: Python returns success on max-attempts; .NET/Java/JS throw - documented in design doc.) Adds 41 unit tests + 5 integration tests covering each wait strategy, isDone predicate paths, max-attempts exhaustion, user-check exceptions, replay determinism, exponential backoff bounds, and corrupt-payload fallback logging. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Copilot

Pull request overview

Adds a new polling primitive (IDurableContext.WaitForConditionAsync) to Amazon.Lambda.DurableExecution, enabling service-mediated polling where each polling iteration runs in its own Lambda invocation (suspended/resumed via durable execution checkpoints). This expands the DurableExecution orchestration surface area with wait strategies, deterministic replay behavior, and supporting infrastructure plus unit/integration/AOT tests.

Changes:

Introduces WaitForConditionAsync API surface, wait strategies (WaitStrategy.*), and supporting config/result types (WaitForConditionConfig<TState>, WaitDecision, IWaitStrategy<TState>, IConditionCheckContext, WaitForConditionException).
Adds core internal plumbing for durable execution (checkpoint batching, deterministic operation IDs, replay state tracking, wait operation, termination/suspension mechanism, SDK service client mapping).
Adds substantial unit/integration coverage and an AOT publish smoke test project.

Reviewed changes

Copilot reviewed 114 out of 115 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
Libraries/test/Amazon.Lambda.DurableExecution.Tests/WaitStrategyTests.cs	Unit tests for wait strategy factories and `WaitDecision` behavior.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/UpperSnakeCaseEnumConverterTests.cs	Unit tests for enum wire-format JSON converter.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/TerminationManagerTests.cs	Unit tests for termination signaling/suspension coordination.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/RetryStrategyTests.cs	Unit tests for retry strategies and exponential backoff behavior.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/RecordingBatcher.cs	Test helper to capture flushed checkpoint batches.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/OperationIdGeneratorTests.cs	Unit tests for deterministic operation ID generation/hashing.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/ModelsTests.cs	Unit tests for model serialization and basic shape.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/MockLambdaClient.cs	Mock `AmazonLambdaClient` for service client tests.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/LambdaDurableServiceClientTests.cs	Unit tests for durable execution service client request/response mapping.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/ExecutionStateTests.cs	Unit tests for replay state tracking and operation lookup.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/ExceptionsTests.cs	Unit tests for exception types and properties.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/EnumsTests.cs	Unit tests for enum/constants shapes and values.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/DurableExecutionHandlerTests.cs	Unit tests for handler termination vs user-code completion race.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/coverage.sh	Local helper script for collecting and reporting coverage.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/coverage.runsettings	Coverage configuration for durable execution tests.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/ConfigTests.cs	Unit test for serialization context record equality.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/CheckpointBatcherTests.cs	Unit tests for batching, flushing, and error propagation semantics.
Libraries/test/Amazon.Lambda.DurableExecution.Tests/Amazon.Lambda.DurableExecution.Tests.csproj	New unit test project configuration and dependencies.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/xunit.runner.json	Integration test runner configuration (serial execution).
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/WaitOnlyTest.cs	Integration test validating wait-only suspend/resume behavior.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/WaitForConditionUserCheckThrowsTest.cs	Integration test for user check exception surfacing as `StepException`.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/WaitForConditionReplayDeterminismTest.cs	Integration test verifying replay determinism around polling.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/WaitForConditionMaxAttemptsTest.cs	Integration test for max-attempts exhaustion and error checkpointing.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/WaitForConditionHappyPathTest.cs	Integration test for successful polling completion.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/WaitForConditionExponentialTest.cs	Integration test for exponential wait strategy end-to-end.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitOnlyFunction/WaitOnlyFunction.csproj	Integration test function project for wait-only workflow.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitOnlyFunction/Function.cs	Wait-only durable workflow test function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitOnlyFunction/Dockerfile	Container image for wait-only test function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionUserCheckThrowsFunction/WaitForConditionUserCheckThrowsFunction.csproj	Integration test function project for user-check-throws scenario.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionUserCheckThrowsFunction/Function.cs	Durable workflow test function that throws from polling check.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionUserCheckThrowsFunction/Dockerfile	Container image for user-check-throws test function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionReplayDeterminismFunction/WaitForConditionReplayDeterminismFunction.csproj	Integration test function project for replay determinism with polling.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionReplayDeterminismFunction/Function.cs	Workflow combining steps + polling to assert deterministic replay.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionReplayDeterminismFunction/Dockerfile	Container image for replay determinism test function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionMaxAttemptsFunction/WaitForConditionMaxAttemptsFunction.csproj	Integration test function project for max-attempts exhaustion path.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionMaxAttemptsFunction/Function.cs	Workflow that catches `WaitForConditionException` and reports attempts.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionMaxAttemptsFunction/Dockerfile	Container image for max-attempts test function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionHappyPathFunction/WaitForConditionHappyPathFunction.csproj	Integration test function project for successful polling path.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionHappyPathFunction/Function.cs	Workflow that polls until `isDone` and returns final state.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionHappyPathFunction/Dockerfile	Container image for happy-path polling function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionExponentialFunction/WaitForConditionExponentialFunction.csproj	Integration test function project for exponential polling behavior.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionExponentialFunction/Function.cs	Workflow using exponential wait strategy with predictable timing.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/WaitForConditionExponentialFunction/Dockerfile	Container image for exponential polling function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/StepWaitStepFunction/StepWaitStepFunction.csproj	Integration test function project for step-wait-step scenario.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/StepWaitStepFunction/Function.cs	Workflow with step → wait → step to validate suspend/resume replay.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/StepWaitStepFunction/Dockerfile	Container image for step-wait-step function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/StepFailsFunction/StepFailsFunction.csproj	Integration test function project for step failure scenario.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/StepFailsFunction/Function.cs	Workflow that throws inside a step to validate failure propagation.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/StepFailsFunction/Dockerfile	Container image for failing-step function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/RetryFunction/RetryFunction.csproj	Integration test function project for retry behavior.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/RetryFunction/Function.cs	Workflow using retry strategy to validate service-driven retries.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/RetryFunction/Dockerfile	Container image for retry function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/ReplayDeterminismFunction/ReplayDeterminismFunction.csproj	Integration test function project for replay determinism via wait boundary.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/ReplayDeterminismFunction/Function.cs	Workflow that ensures cached step output persists across replay.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/ReplayDeterminismFunction/Dockerfile	Container image for replay determinism function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/MultipleStepsFunction/MultipleStepsFunction.csproj	Integration test function project for multi-step chaining.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/MultipleStepsFunction/Function.cs	Workflow with five steps to validate checkpointing order.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/MultipleStepsFunction/Dockerfile	Container image for multi-step function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/LongerWaitFunction/LongerWaitFunction.csproj	Integration test function project for longer waits.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/LongerWaitFunction/Function.cs	Workflow with longer wait to validate timer behavior and replay.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/TestFunctions/LongerWaitFunction/Dockerfile	Container image for longer-wait function.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/StepWaitStepTest.cs	Integration assertions for step-wait-step workflow.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/StepFailsTest.cs	Integration assertions for workflow failure behavior.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/RetryTest.cs	Integration assertions for service-mediated retries and timing.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/ReplayDeterminismTest.cs	Integration assertions for deterministic replay caching via wait.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/MultipleStepsTest.cs	Integration assertions for multi-step checkpointing consistency.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/LongerWaitTest.cs	Integration assertions for longer wait and multi-invocation behavior.
Libraries/test/Amazon.Lambda.DurableExecution.IntegrationTests/Amazon.Lambda.DurableExecution.IntegrationTests.csproj	New integration test project and AWS SDK dependencies.
Libraries/test/Amazon.Lambda.DurableExecution.AotPublishTest/Program.cs	NativeAOT publish smoke test exercising source-gen serializer path.
Libraries/test/Amazon.Lambda.DurableExecution.AotPublishTest/Amazon.Lambda.DurableExecution.AotPublishTest.csproj	NativeAOT/trim configuration for publish smoke test.
Libraries/src/Amazon.Lambda.DurableExecution/Services/LambdaDurableServiceClient.cs	Service client wrapper for checkpoint/state APIs (SDK interop).
Libraries/src/Amazon.Lambda.DurableExecution/Models/ErrorObject.cs	Serializable error representation for checkpoints/envelopes.
Libraries/src/Amazon.Lambda.DurableExecution/Models/DurableExecutionInvocationOutput.cs	Public output envelope model and JSON annotations.
Libraries/src/Amazon.Lambda.DurableExecution/Models/DurableExecutionInvocationInput.cs	Public input envelope model and internal replay state container.
Libraries/src/Amazon.Lambda.DurableExecution/Internal/WaitOperation.cs	Durable wait operation implementation (service-timer suspension).
Libraries/src/Amazon.Lambda.DurableExecution/Internal/UpperSnakeCaseEnumConverter.cs	JSON converter for UPPER_SNAKE_CASE enum wire format.
Libraries/src/Amazon.Lambda.DurableExecution/Internal/TerminationManager.cs	Termination/suspension signal coordination for orchestration.
Libraries/src/Amazon.Lambda.DurableExecution/Internal/ReflectionJsonCheckpointSerializer.cs	Reflection-based default checkpoint serializer with trim/AOT annotations.
Libraries/src/Amazon.Lambda.DurableExecution/Internal/OperationIdGenerator.cs	Deterministic operation ID generator compatible with other SDKs.
Libraries/src/Amazon.Lambda.DurableExecution/Internal/Operation.cs	Internal operation wire-model and constant strings.
Libraries/src/Amazon.Lambda.DurableExecution/Internal/ExponentialBackoff.cs	Shared exponential backoff delay calculation helper.
Libraries/src/Amazon.Lambda.DurableExecution/Internal/ExecutionState.cs	Replay-state hydration, lookup, and replay-frontier tracking.
Libraries/src/Amazon.Lambda.DurableExecution/Internal/DurableOperation.cs	Base class for durable operations with start/replay dispatch.
Libraries/src/Amazon.Lambda.DurableExecution/Internal/ChildContextOperation.cs	Durable child-context operation with checkpointed result/failure.
Libraries/src/Amazon.Lambda.DurableExecution/Internal/CheckpointBatcherConfig.cs	Configuration for outbound checkpoint batching.
Libraries/src/Amazon.Lambda.DurableExecution/Internal/CheckpointBatcher.cs	Background worker batching/flushing checkpoint updates.
Libraries/src/Amazon.Lambda.DurableExecution/IDurableContext.cs	Public durable context API surface (steps, waits, child contexts, polling).
Libraries/src/Amazon.Lambda.DurableExecution/IConditionCheckContext.cs	Context passed to wait-for-condition check function.
Libraries/src/Amazon.Lambda.DurableExecution/ICheckpointSerializer.cs	Public checkpoint serializer abstraction and serialization context record.
Libraries/src/Amazon.Lambda.DurableExecution/Exceptions/WaitForConditionException.cs	Exception type for polling exhaustion with last-state capture.
Libraries/src/Amazon.Lambda.DurableExecution/Exceptions/DurableExecutionException.cs	Base exception and related durable execution exception types.
Libraries/src/Amazon.Lambda.DurableExecution/Enums.cs	Public invocation status enum.
Libraries/src/Amazon.Lambda.DurableExecution/DurableExecutionHandler.cs	Core orchestration runner (user code vs termination race).
Libraries/src/Amazon.Lambda.DurableExecution/Config/WaitStrategy.cs	Wait strategy factories and built-in strategy implementations.
Libraries/src/Amazon.Lambda.DurableExecution/Config/WaitForConditionConfig.cs	Configuration container for polling operations.
Libraries/src/Amazon.Lambda.DurableExecution/Config/WaitDecision.cs	Strategy decision struct for continue/stop + delay.
Libraries/src/Amazon.Lambda.DurableExecution/Config/StepConfig.cs	Step execution configuration (retry/semantics).
Libraries/src/Amazon.Lambda.DurableExecution/Config/RetryStrategy.cs	Retry strategy factories and implementations, jitter/backoff options.
Libraries/src/Amazon.Lambda.DurableExecution/Config/IWaitStrategy.cs	Interface for wait strategies used by polling.
Libraries/src/Amazon.Lambda.DurableExecution/Config/IRetryStrategy.cs	Interface for retry strategies used by steps.
Libraries/src/Amazon.Lambda.DurableExecution/Config/ChildContextConfig.cs	Configuration for child contexts (subtype, error mapping).
Libraries/src/Amazon.Lambda.DurableExecution/Amazon.Lambda.DurableExecution.csproj	New durable execution library project definition and dependencies.
CONTRIBUTING.md	Adds `Amazon.Lambda.DurableExecution` to documented projects list.
buildtools/build.proj	Adds durable execution unit tests to the build/test pipeline.
.autover/autover.json	Registers new package for automated versioning.

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+using Amazon.Lambda.DurableExecution.Internal;
+using Amazon.Lambda.Model;
+using SdkOperationUpdate = Amazon.Lambda.Model.OperationUpdate;
+using SdkOperation = Amazon.Lambda.Model.Operation;


+                Error = sdkOp.StepDetails.Error != null ? new ErrorObject
+                {
+                    ErrorType = sdkOp.StepDetails.Error.ErrorType,
+                    ErrorMessage = sdkOp.StepDetails.Error.ErrorMessage
+                } : null,


+                Error = sdkOp.ContextDetails.Error != null ? new ErrorObject
+                {
+                    ErrorType = sdkOp.ContextDetails.Error.ErrorType,
+                    ErrorMessage = sdkOp.ContextDetails.Error.ErrorMessage
+                } : null


+using System.Text.Json;
+using System.Text.Json.Serialization;


GarrettBeatty and others added 5 commits May 11, 2026 23:03

add design doc (#2361)

d9638e6

stack-info: PR: #2361, branch: GarrettBeatty/stack/3

Add Amazon.Lambda.DurableExecution project scaffolding (#2359)

1fb7f7f

Retry

7ca2099

stack-info: PR: #2363, branch: GarrettBeatty/stack/3

github-advanced-security AI found potential problems May 14, 2026

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GarrettBeatty and others added 2 commits May 14, 2026 17:47

GarrettBeatty force-pushed the gcbeatty/durable-wave0 branch from 464c591 to d308c3b Compare May 14, 2026 21:49

GarrettBeatty force-pushed the gcbeatty/durable-waitforcondition branch from 87688ca to 7f91202 Compare May 14, 2026 21:49

GarrettBeatty force-pushed the gcbeatty/durable-waitforcondition branch from 7f91202 to 3fa06ce Compare May 14, 2026 22:19

GarrettBeatty force-pushed the gcbeatty/durable-wave0 branch from d308c3b to be4c3ad Compare May 18, 2026 15:23

GarrettBeatty force-pushed the gcbeatty/durable-waitforcondition branch from 3fa06ce to 67f0c0c Compare May 18, 2026 15:50

GarrettBeatty force-pushed the gcbeatty/durable-wave0 branch 3 times, most recently from ad4d208 to 3acbed5 Compare May 20, 2026 17:46

Base automatically changed from gcbeatty/durable-wave0 to gcbeatty/durable-child-context May 20, 2026 17:46

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GarrettBeatty force-pushed the gcbeatty/durable-waitforcondition branch from b007169 to 1a9a000 Compare June 1, 2026 22:01

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Add WaitForConditionAsync polling primitive (DOTNET-8665)#2376

Add WaitForConditionAsync polling primitive (DOTNET-8665)#2376
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GarrettBeatty commented May 14, 2026 •

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		COPY bin/publish/ ${LAMBDA_TASK_ROOT}

		ENTRYPOINT ["/var/task/bootstrap"]

		using System.Text.Json;
		using System.Text.Json.Serialization;

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GarrettBeatty commented May 14, 2026 •

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