Temporal Design Patterns
Temporal provides a set of durable execution primitives that you can compose into common, reusable, and proven patterns. Having these patterns in your toolbox helps you solve recurring problems in a battle-tested way.
Task orchestration patterns
Child Workflows
Decomposes complex Workflows into smaller, reusable units. Each child has an independent Workflow ID, history, and lifecycle.
Parallel Execution
Executes multiple Activities concurrently for maximum throughput with error handling and controlled parallelism.
Pick First (Race)
Races multiple Activities in parallel, returns the first completed result, and cancels the remaining Activities using SDK cancellation scopes.
Workflow messaging patterns
Signal with Start
Starts a Workflow when Signaling it if it does not already exist. If already running, it receives the Signal directly.
Request-Response via Updates
Uses a Workflow Update to validate a request, modify Workflow state, and return a typed result to the caller synchronously, with strong consistency.
Event Accumulator
Durably collect and deduplicate signals from multiple senders, then process the batch after a sliding inactivity timeout.
Entity & lifecycle patterns
Entity Workflow
A long-lived business entity — a user account, device, or order — gets one Workflow per instance, with Signals and Updates driving every state transition.
Continue-As-New
Prevents unbounded history growth by completing the current execution and starting a new one with fresh history.
Updatable Timer
Dynamically adjustable timers that respond to Signals or Updates. Extend, shorten, or cancel timers based on external events.
External interaction patterns
Polling External Services
Strategies for polling external resources with varying frequencies: frequent, infrequent, and periodic patterns.
Long-Running Activity
Long-running Activities report progress via heartbeats and enable resumption after failures with cancellation support.
Delayed Start
Creates Workflows immediately but defers execution until a specified delay expires. Fits one-time scheduled operations and grace periods.
Delayed Callback (Webhooks)
Webhooks become durable: inbound calls arrive as Signals, outbound calls fire after a durable sleep, and Activities complete later via task tokens.
Approval
Human-in-the-loop Workflows that block until external approval decisions are made. Uses Signals to capture approval data with metadata.
Distributed transaction patterns
Saga Pattern
Manages distributed transactions with compensating actions. Each step has a compensation that undoes its effects if subsequent steps fail.
Early Return
Synchronous initialization with asynchronous completion. Returns results immediately while processing continues in the background.
Error handling & retry patterns
Fixed Count of Retries
Cap the number of Activity retry attempts to control cost when each attempt consumes a paid or limited resource.
Fixed Wall-Time Retries
Bound the total elapsed time across all retry attempts to enforce a business SLA, regardless of how many individual attempts occur.
Non-Retryable Errors
Mark error types that will never succeed — such as validation failures or missing records — so Temporal fails fast instead of retrying indefinitely.
Delayed Retry
Override one failure's retry interval with nextRetryDelay on ApplicationFailure, matching the wait time the error reports.
Fast/Slow Retries
Retry fast with a short interval first, then shift to a slow, unlimited interval so the Workflow outlasts an extended downstream outage.
Retry Alerting via Metrics
Emit a metric from the Activity when attempts cross a threshold, so on-call teams see persistent failures before an SLA breach.
Resumable Activity
Park the Workflow after retries are exhausted and wait for a human to signal a correction, then resume execution from where it left off.
Batch processing patterns
Fan-Out with Child Workflows
Distributes a large record set across parallel Child Workflows for concurrent processing with automatic scaling.
Batch Iterator
Pages through unbounded datasets using Continue-As-New to prevent history overflow while maintaining exactly-once processing guarantees.
Sliding Window
Maintains a fixed number of concurrently active Child Workflows, starting a new one each time an existing one completes.
MapReduce Tree
Recursively splits a dataset into a binary tree of Child Workflows, processes leaves in parallel, then aggregates results back up the tree.
QoS & throughput patterns
Downstream Rate Limiting
Rate-limits calls to a downstream service by routing throttled Activities to a dedicated Task Queue with a server-enforced throughput cap.
Priority
Assigns a priority level to Workflows and Activities so that time-sensitive work dispatches ahead of lower-priority work within a single Task Queue.
Fairness
Distributes Task dispatches across tenants or users so that a burst from one caller does not starve the others.
Performance & latency patterns
Local Activities
Local Activities run inside the Worker process, skipping server round-trips for short, idempotent Activities on a latency-sensitive path.
Early Return + Local Activities
Extends Early Return by running Phase 1 as Local Activities, so the client's first response comes from in-process work, not a server call.
Eager Workflow Start
Eager Workflow Start sends the first Workflow Task directly to a co-located Worker, skipping the Matching Service to cut startup latency.
