# fonoster/fonoster

🚀 The open-source alternative to Twilio.

Repository: https://github.com/fonoster/fonoster
Canonical: https://ross.abutalabs.com/products/fonoster
Homepage: https://fonoster.com
Language: TypeScript
License: MIT
License Family: permissive
Topics: cloud-communications-platform, twilio, ucaas, kubernetes, voip, programmable-voice, webrtc, telephony, cloud, cpaas, customer-engagement, javascript, nodejs, typescript, customer-experience
Last push: 2026-08-26T03:00:39+00:00

## Health v2 (maintenance only)
Score: 99/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 99, longevity 100
- inputs: {"age_days": 3132, "days_push": 7, "days_rel": 8, "gap_med": 5.5, "n_releases_24m": 9}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 8080, forks 548 (observed 2026-08-28T04:10:12.552929+00:00)

## What it is
Fonoster is an open-source programmable telecommunications stack (a Twilio alternative) for building voice and messaging applications, with multitenancy, OAuth2/JWT auth, RBAC, and a Node.js SDK. It supports voice verbs like Answer, Say, Gather, Dial, and Record, plus speech APIs from Google, Deepgram, and ElevenLabs, and can be self-hosted on Kubernetes.

## Use cases
- build an IVR without Twilio
- self-host a programmable voice platform
- make outbound calls from an API
- add text-to-speech and speech recognition to phone calls
- record and transcribe calls
- create a cloud PBX for my business
- build a voice AI agent that answers phone calls
- stream audio to and from a caller over WebRTC

## When to choose
- you want Twilio-like programmable voice without per-minute vendor lock-in
- you need to self-host your telephony infrastructure
- you're building voice AI agents, IVRs, or call recording workflows in Node.js or TypeScript

## When to avoid
- you only need simple SMS messaging with no voice features
- you can't operate your own SIP trunks or Kubernetes infrastructure
- you need a fully managed service with guaranteed SLAs today

## Facets
- artifact type: service
- maturity: active
- function: api-framework, sdk, speech-recognition, tts, cli, auth, self-hosted
- domain: cloud-computing, apis, developer-tools, speech-processing, self-hosted
- platform: self-hosted, cli, cross-platform
- tags: twilio-alternative, voip, webrtc, programmable-voice, cpaas, ucaas, ivr, voice-ai, pbx, telephony-api, telephony, nodejs, kubernetes, docker, web-server

## Member repositories
- fonoster/fonoster (main) score 99

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:10:12.552929+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 2026-08-29T17:31:20.308399+00:00, confidence not recorded.
  - readme: https://github.com/fonoster/fonoster (fetched 2026-08-28T04:10:12.552929+00:00, sha b4dd20fa5809)
  - homepage: https://fonoster.com (fetched 2026-08-29T08:29:18.467872+00:00, sha bd5598051987)
  - site_page: https://docs.fonoster.com/ (fetched 2026-08-29T08:29:18.477689+00:00, sha c4cdc59e6990)
- Data as of 2026-08-30T08:39:29.467469+00:00.