Temporal is an open-source durable execution platform from Temporal Technologies Inc. Durable execution means that the state of a running program is saved at every step, so the program continues exactly where it stopped after a crash, a network failure or an outage, even days later.
A developer writes the business logic as a Workflow in ordinary code, with SDKs for Go, Java, Python, TypeScript, .NET, PHP, Ruby and Rust. Steps that can fail, such as calls to outside APIs, are written as Activities: functions that Temporal retries automatically. The Temporal Service stores the event history of each workflow and provides retries, task queues, signals (messages sent into a running workflow), durable timers and cron schedules. A workflow can run for days, weeks or months, and the state of each run can be inspected while it runs.
The Temporal Service is open source under the MIT license and can be self-hosted. Temporal Cloud is the hosted version, billed per use for actions and storage, with no base monthly fee.