Open Source Alternatives to Sierra
7 open source Conversational AI options similar to Sierra, ranked by named competitors first, sector overlap, and our 0-100 AI-readiness score. Every company listed publishes its source: each one carries an open source sector tag and a public GitHub repository.
Vocode50Open SourceSan Francisco, United States$3.8MOpen-source library for building hyper-realistic voice agents and conversational AI applications.
Open source · Self-hostable
Rasa49Conversational AIBerlin, Germany$13.0MOpen-source conversational AI platform for building custom chatbots and virtual assistants.
Open source · Self-hostable
CRAB27Agentic AIAn open-source framework for building, operating, and benchmarking Multimodal Language Model (MLM) agents across diverse environments.
Open source · Self-hostable
Kyutai68Frontier AI LabParis, France$300.0MA non-profit AI research lab focused on open science and developing advanced multimodal and voice AI models.
Open source · Self-hostable
Coqui48Voice AIBerlin, Germany$2.0MOpen-source AI models for voice synthesis, translation, and TTS.
Open source · Self-hostable
Velorn12AI Video GenerationAI-native video editing and generative production tools built around a creative timeline.
Open source
Talkcan7Open SourceAn open-source programmable walkie-talkie for routing voice through configurable channels.
Open source