Flagd

Judgement

What it is

Building block

What it does

A small feature-flag daemon that evaluates flags from files, HTTP or Kubernetes sources and serves them to OpenFeature SDKs.

Adopt it when

You want vendor-neutral feature flags through OpenFeature without buying a flag service.

Watch out

No management UI; flags are edited as config files.

Ready for

Usable

Runs as

Self-hosted server

Built with

Go

How established

Established: started 4 years ago, latest release core/v0.19.2.

What the license allows

You can build it into a product you sell, as long as you keep its copyright notice.

Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: Flagd → Go → runs on a microchip

How compilers were built, back to punched paper tape

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