# spinframework/spin

Spin is the open source developer tool for building and running serverless applications powered by WebAssembly.

Repository: https://github.com/spinframework/spin
Canonical: https://ross.abutalabs.com/products/spin
Homepage: https://spinframework.dev
Language: Rust
License: Apache-2.0
License Family: permissive
Topics: webassembly, spin, serverless
Last push: 2026-08-26T18:37:42+00:00

## Health v2 (maintenance only)
Score: 95/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 87, longevity 100
- inputs: {"age_days": 1766, "days_push": 7, "days_rel": 7, "gap_med": 32.0, "n_releases_24m": 19}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 6505, forks 311 (observed 2026-08-28T04:09:43.923856+00:00)

## What it is
Spin is an open-source framework and CLI for building, deploying, and running event-driven serverless microservices as WebAssembly components, built on Wasmtime and the WebAssembly component model. It supports SDKs for Rust, JavaScript, Go, and Python, with triggers for HTTP, Redis, cron, and MQTT, plus built-in key-value, SQLite, and AI interfaces.

## Use cases
- build serverless microservices with webassembly
- run wasm apps with millisecond cold starts
- deploy event-driven http apis on kubernetes
- write polyglot microservices in rust go python or javascript
- self-host a lightweight serverless runtime
- build mcp servers with webassembly
- run cron-triggered background jobs as wasm components

## When to choose
- you want sandboxed, fast cold-start serverless functions without managing containers
- you want to write microservices in multiple languages compiled to a portable Wasm runtime
- you want to run serverless workloads on Kubernetes (SpinKube) or self-hosted servers
- you need event-driven triggers like HTTP, Redis, cron, or MQTT with Wasm isolation

## When to avoid
- you need long-running, always-on services rather than short-lived event-driven functions
- your dependencies require native libraries or system access unavailable in the Wasm sandbox
- your team has no appetite for the WebAssembly component model toolchain
- you need a mature managed FaaS platform with broad ecosystem integrations out of the box

## Facets
- artifact type: framework
- maturity: active
- function: web-framework, http-server, serverless, wasm, cli, microservices, scheduling, caching, database, mcp
- domain: web-development, backend, cloud-computing, developer-tools, apis
- platform: windows, cli, self-hosted, cloud, rust, go, python
- tags: webassembly, wasmtime, wasi, serverless-framework, cnfc-sandbox, event-driven, cold-start, spin, fermyon, component-model, containers, linux, macos, docker, kubernetes, nodejs

## Member repositories
- spinframework/spin (main) score 95

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:43.923856+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 2026-08-29T17:44:28.437945+00:00, confidence not recorded.
  - readme: https://github.com/spinframework/spin (fetched 2026-08-28T04:09:43.923856+00:00, sha 73f8a69fbd16)
  - homepage: https://spinframework.dev (fetched 2026-08-29T08:41:08.676558+00:00, sha 9661d189c27b)
  - site_page: https://spinframework.dev/quickstart (fetched 2026-08-29T08:41:08.680849+00:00, sha 09c597f8a53c)
  - site_page: https://spinframework.dev/v4/quickstart (fetched 2026-08-29T08:41:08.683493+00:00, sha 804d812a84ad)
  - site_page: https://spinframework.dev/v4/install (fetched 2026-08-29T08:41:08.685884+00:00, sha a0e2ded5fc84)
  - site_page: https://spinframework.dev/v4/contributing-docs (fetched 2026-08-29T08:41:08.688147+00:00, sha 0cb3cd14e363)
  - site_page: https://spinframework.dev/blog/index (fetched 2026-08-29T08:41:08.679070+00:00, sha 339803f9a336)
- Data as of 2026-08-30T08:39:29.467469+00:00.