Open Source Go LLM Gateways

Bifrost is an LLM gateway designed to provide a unified OpenAI-compatible API front for many different model providers. It abstracts away the complexity of working directly with multiple backend providers (OpenAI, Anthropic, AWS Bedrock, Google Vertex, etc.), enabling you to plug in providers and switch between them without touching your client code. It is built to be high performance: in benchmark tests at 5,000 requests per second, it reportedly adds only microseconds of overhead and achieves perfect success rates with no failed requests. Bifrost supports features such as automatic fallback (failover between providers), load balancing across API keys/providers, and semantic caching to reduce latency and cost. It also includes observability with built-in metrics, tracing, logging, and supports governance features like rate limiting, access control, and cost budgeting. The architecture is modular: there is a core engine, plugin layers, and transport layers (HTTP APIs).