Atmosphere

Atmosphere is an open source real time framework for the Java Virtual Machine that has grown into a platform for building governed, durable AI agents. Async IO is the company behind it and sells commercial support. The framework carries agent traffic over five transports, WebSocket, server sent events, HTTP streaming, long polling and WebTransport over HTTP/3, and speaks the MCP, A2A and AG UI agent protocols. It is aimed at Java teams putting agents into production. A single service provider interface fronts twelve AI runtimes, so a team can swap runtimes by changing a dependency while keeping its code. Durable runs record each step and replay deterministically, so an agent resumes where it stopped after a JVM restart, with snapshots stored in memory, SQLite or Postgres. Tools marked for approval pause at a human gate, governance policies run before the model and can block a call, and a plan mode lets a static verifier check an agent's plan against policy before anything executes. A built in console covers chat, sessions, checkpoints, observability, policies and multi agent coordination, and compliance mappings for the OWASP agentic top ten, the EU AI Act, HIPAA and SOC 2 ship with the source. The framework itself is free on GitHub. Support subscriptions are priced per organisation per year: Developer at $2,000 for development and evaluation, with next business day response and 5 incidents a year; Production at $9,000, with four business hour response, unlimited incidents, phone support and emergency patches; and Mission Critical from $25,000 on a quote, with one hour response around the clock. Async IO also offers long term support and migration help for teams still running Atmosphere 2.x or 3.x.