Fonoster
The open-source alternative to Twilio.
Fonoster is an open-source platform for engaging customers through voice or messaging, providing tooling to build and deploy voice applications. It addresses the need to create voice applications with support for verbs such as Play, Say, and Gather, alongside project-level authentication and sound storage.
The platform includes SDKs for browser and Node.js applications, a CLI for creating and deploying applications, and Speech APIs for text-to-speech and automatic speech recognition. Authentication is handled at the project level using OAuth2 and JWT tokens, and sounds can be stored on S3 buckets. The voice application tooling exposes a CallManager interface for handling calls.
Fonoster is packaged with a free rate-limited plan for prototyping, a Pro plan for small and medium businesses moving applications into production with usage-based minutes, and an advanced edition with technical support, SLAs, and volume commitment pricing. The open-source version can be self-hosted for free.
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