# metacontroller/metacontroller

Writing kubernetes controllers can be simple

Repository: https://github.com/metacontroller/metacontroller
Canonical: https://ross.abutalabs.com/products/metacontroller
Homepage: https://metacontroller.github.io/metacontroller
Language: Go
License: Apache-2.0
License Family: permissive
Topics: kubernetes, metacontroller
Last push: 2026-08-27T20:03:49+00:00

## Health v2 (maintenance only)
Score: 98/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 97, longevity 100
- inputs: {"age_days": 2297, "days_push": 6, "days_rel": 20, "gap_med": 5.5, "n_releases_24m": 35}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1005, forks 105 (observed 2026-09-03T02:15:14.931160+00:00)

## What it is
Metacontroller is a Kubernetes add-on that lets you write and deploy custom controllers as simple webhook scripts in any language. It handles watches, caching, work queues, retries, and level-triggered reconciliation so you only provide JSON-in/JSON-out logic.

## Use cases
- write a kubernetes custom controller without go boilerplate
- build a kubernetes operator in python or javascript
- add custom automation logic on top of existing kubernetes apis
- create reusable crd-based abstractions for my cluster
- implement statefulset-like behavior with custom resources
- deploy controller hooks as simple http webhooks

## When to choose
- you want custom Kubernetes controller behavior without maintaining a full Go controller with informers and client libraries
- you want to write controller logic in any language via a JSON webhook
- you want built-in production features like caching, retries, garbage collection, and adopt/orphan semantics
- you want to compose existing Kubernetes APIs into higher-level declarative abstractions

## When to avoid
- you need fine-grained control over the reconcile loop or controller internals
- you prefer a full-featured operator SDK with generated code and typed clients
- you cannot run an additional add-on and webhook endpoints in your cluster
- you need sub-millisecond reaction times, since webhooks add latency

## Facets
- artifact type: framework
- maturity: active
- function: webhook, middleware, workflow-automation, developer-tools
- domain: cloud-computing, infrastructure-as-code
- platform: go, cloud, self-hosted
- tags: kubernetes-controllers, custom-resources, operators, crd, webhook-hooks, declarative-apis, kubernetes, devops, automation, docker

## Member repositories
- metacontroller/metacontroller (main) score 98

## Provenance
- Observed fields: from GitHub, fetched 2026-09-03T02:15:14.931160+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T07:13:53.916009+00:00, confidence not recorded.
  - readme: https://github.com/metacontroller/metacontroller (fetched 2026-09-03T02:15:14.931160+00:00, sha 51753cfcaec4)
  - homepage: https://metacontroller.github.io/metacontroller (fetched 2026-08-29T13:13:40.804567+00:00, sha 741969c5dcff)
- Data as of 2026-08-30T08:39:29.467469+00:00.