Temporal is an open-source durable execution platform that enables developers to build reliable distributed applications and long-running workflows using familiar programming languages. Unlike traditional workflow engines that use DSLs or visual editors, Temporal allows developers to write workflow logic as ordinary code in Go, Java, TypeScript, Python, or .NET. The platform guarantees that workflow code will run to completion despite infrastructure failures, process crashes, or network outages through its durable execution model, which transparently persists the state of every function call.

Temporal’s architecture consists of the Temporal Server (a scalable, multi-tenant orchestration service) and Worker processes (application code that executes workflow and activity logic). Workflows define the overall orchestration logic and are deterministic, while Activities perform the actual work (API calls, database operations, computations) and can be retried with configurable policies. The platform provides features including workflow timeouts, activity retries with exponential backoff, signal handling for external events, query handling for workflow state inspection, child workflows for composition, saga patterns for compensation logic, and cron scheduling. Temporal Server uses Cassandra, MySQL, or PostgreSQL for persistence and supports horizontal scaling to handle millions of concurrent workflows.

Temporal is used by companies including Netflix, Snap, Stripe, Datadog, and HashiCorp for use cases spanning payment processing, order fulfillment, infrastructure provisioning, CI/CD pipelines, and data processing. Its code-first approach and strong reliability guarantees have made it a popular choice for critical business processes that span multiple services and require transactional consistency.

Key Capabilities

  • Durable Execution - Transparent state persistence that guarantees workflow completion despite arbitrary infrastructure failures
  • Multi-Language SDKs - Write workflows in Go, Java, TypeScript, Python, and .NET using native language constructs and debugging tools
  • Activity Retries - Configurable retry policies with exponential backoff, maximum attempts, timeouts, and heartbeating for long-running activities
  • Visibility and Observability - Searchable workflow execution history, real-time state queries, and integration with standard observability tools

Cloud Equivalents

Temporal is the open-source alternative to AWS Step Functions, Azure Durable Functions, and Google Cloud Workflows. Cloud workflow services use declarative state machines (JSON/YAML), while Temporal allows writing workflows as imperative code with full language features. This code-first approach is more expressive but requires running Temporal Server infrastructure.

Origins and History

Temporal was created by Maxim Fateev and Samar Abbas, who previously built Uber’s Cadence workflow engine. They founded Temporal Technologies in 2019 to create an improved, open-source version of Cadence. The Temporal Server is licensed under the MIT License, and SDKs are under the Apache License 2.0. Temporal Technologies has raised over $200 million in venture funding. Temporal Cloud, a managed SaaS offering, launched in 2022. The system’s intellectual lineage traces back through Cadence (Uber), Amazon Simple Workflow Service (SWF), and Microsoft’s Durable Task Framework.

Sources

  1. https://temporal.io/
  2. https://github.com/temporalio/temporal