When using Braintrust as part of an LLM development workflow, users have the flexibility and control over their data by deploying it in a hybrid mode. This approach allows for the hosting of sensitive data in the user's own environment while keeping the UI and metadata hosted by Braintrust. The architecture consists of two main components: the data plane and the control plane, where the data plane handles the actual data and is hosted in the user's environment, while the control plane serves the UI and metadata and is hosted by Braintrust. This hybrid model provides security and compliance with the ability to update features automatically, configure rate limits, custom URLs, and domain proxies to meet IT environment and security policies. Users can self-host on their preferred infrastructure, including AWS, using pre-provided configuration files or templates, and receive support for advanced deployment scenarios.