# PatterAI/Patter

Open-source voice-AI SDK. The Vapi/Retell alternative for builders who want to own the stack. Give your AI agent a phone number in 4 lines — Python and TypeScript, MIT licensed, Twilio, Telnyx, and Plivo.

Repository: https://github.com/PatterAI/Patter
Canonical: https://ross.abutalabs.com/products/patter
Homepage: https://getpatter.com
Language: Python
License: MIT
License Family: permissive
Topics: open-source, openai, python, sdk, speech-to-text, telnyx, text-to-speech, twilio, typescript, voice-ai, ai-agent, llm, ai-phone-agent, realtime-api, vapi-alternative, voice-agent, voicebot, openclaw, hermes-agent, mastra
Last push: 2026-08-25T04:39:14+00:00

## Health v2 (maintenance only)
Score: 78/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 99, release rhythm 90, longevity 10
- inputs: {"age_days": 148, "days_push": 8, "days_rel": 64, "gap_med": 4.0, "n_releases_24m": 17}
- flags: young
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1039, forks 116 (observed 2026-08-28T04:03:19.863247+00:00)

## What it is
Patter is an open-source, MIT-licensed SDK (Python and TypeScript) that connects AI agents to real phone calls, handling telephony, speech-to-text, text-to-speech, and real-time audio streaming. It lets developers pick providers per layer (LLM, STT, TTS, carrier like Twilio/Telnyx/Plivo) and runs self-hosted with no per-minute platform fees.

## Use cases
- give my AI agent a phone number
- build a voice bot that answers phone calls
- open-source alternative to Vapi or Retell
- connect an LLM agent to Twilio calls
- build an AI receptionist that takes phone calls
- run speech-to-text and text-to-speech pipeline for phone calls
- self-host voice AI without per-minute fees

## When to choose
- you want to own the full voice stack and self-host it
- you need provider flexibility across LLM, STT, TTS, and carriers
- you want Python and TypeScript SDKs with API parity
- you want to avoid per-minute charges from hosted voice-AI platforms

## When to avoid
- you want a fully managed hosted service with no infrastructure to run
- you need a turnkey no-code voice agent builder
- you need telephony providers beyond Twilio, Telnyx, or Plivo

## Facets
- artifact type: library
- maturity: active
- function: speech-recognition, tts, llm-inference, agent-framework, sdk, websocket, audio-processing
- domain: artificial-intelligence, speech-processing, developer-tools
- platform: python, cross-platform, self-hosted
- tags: voice-ai, telephony, twilio, telnyx, plivo, voice-agent, phone-calls, realtime, vapi-alternative, retell-alternative, speech-to-text, text-to-speech, mit-license, ai-agents, automation, nodejs

## Member repositories
- PatterAI/Patter (main) score 78

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:19.863247+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 2026-08-30T07:03:34.303397+00:00, confidence not recorded.
  - readme: https://github.com/PatterAI/Patter (fetched 2026-08-28T04:03:19.863247+00:00, sha b3e29a4d12e5)
  - homepage: https://getpatter.com (fetched 2026-08-29T13:04:53.739093+00:00, sha 9cf3e384b672)
  - site_page: https://docs.getpatter.com (fetched 2026-08-29T13:04:53.741953+00:00, sha d01f9148cf6f)
  - site_page: https://www.getpatter.com/about (fetched 2026-08-29T13:04:53.743682+00:00, sha e8c8477cfda8)
- Data as of 2026-08-30T08:39:29.467469+00:00.