Busbar

Busbar is a self hosted AI control plane: a single Rust binary that sits between an organization's applications and its AI providers. Applications point their existing SDK at one Busbar endpoint, and Busbar routes each request, translates between provider protocols in both directions, fails over mid flight when a backend breaks, and enforces keys, budgets and rate limits, all inside the customer's own infrastructure with nothing sent back to the vendor. It is aimed at platform and infrastructure teams running AI features in production. Busbar speaks six wire protocols (OpenAI, Anthropic, Gemini, Bedrock, Cohere and the OpenAI Responses API) and covers chat, embeddings, images, audio, moderations and rerank. Models are defined as named pools in configuration, so an app can request a pool and be served by any provider behind it, with routing policies such as weighted, cheapest, fastest, least busy or usage based. Hooks add programmable middleware on the request path: taps observe traffic for audit or SIEM feeds, and gates can reject, restrict, reroute or rewrite requests for tasks such as PII redaction. It terminates TLS and mutual TLS itself, tracks cost, latency and traffic per request, and ships for Linux, macOS and Windows. Busbar is published under the Apache License 2.0, which permits commercial use, internal or customer facing deployment and private modification without any obligation to publish changes. The site publishes no paid plans or prices; installation is a single command that downloads the binary and the provider catalog. The vendor states that every capability works fully air gapped and that this is a permanent design commitment.