Tableflip is a Go library that enables graceful process restarts for network services. It solves the problem of updating running code and configuration without disrupting existing client connections by implementing a process restart mechanism that transfers clients to a new process before the old one exits. The library coordinates this handoff by starting a new process, giving it a grace period for initialization, and ensuring the old process only exits after a successful upgrade. It enforces that no old code continues running after an upgrade completes, that only a single upgrade runs in parallel, and that crashes during initialization do not leave the service in an inconsistent state.
The tool suits Go-based network services that need zero-downtime deployments and can run on Linux or macOS. It provides more control over the upgrade process than simpler approaches, though developers should be aware that integration with systemd journaling may lose logs on older systemd versions due to a known bug, with workarounds available through direct journald logging.
The project maintains a focused scope on the core graceful restart mechanism. Development activity shows consistent attention to the library's reliability and compatibility with system-level process management, particularly around edge cases in systemd integration. The maintainers have documented known limitations and provided concrete workarounds rather than attempting to hide or work around platform-specific issues.
