Cosine started as an AI software engineer aimed at understanding and working across entire codebases, and has since grown into a sovereign-AI company serving organisations that cannot send sensitive data to third-party frontier models. The product line now centres on the Lumen model family, including Lumen Sovereign—a frontier model trained on the UK's Isambard-AI supercomputer with UK Government backing—alongside Lumen Outpost and Lumen Scout variants for different deployment postures.
Alongside the models, Cosine ships three agent surfaces. Cosine CLI delegates complex engineering tasks to agents that reason across full codebases, write and refactor software, run tests and work autonomously in an existing development environment. Cosine Desktop brings autonomous assistance into everyday desktop workflows for research, document and spreadsheet analysis and coordination across local files and tools. Cosine Cloud assigns long-running work to isolated environments, runs tasks in parallel and lets teams review results together with built-in controls for usage, model access and spend.
Security and sovereignty are the organising principles. Deployments can be fully air-gapped inside a customer's own infrastructure with no external connectivity, run in a dedicated managed single-tenant environment, or accessed through Cosine's managed public cloud. Organisations can also post-train an open-weight model, adapt Lumen Sovereign to their own domain knowledge, or commission an entirely new foundation model built to their requirements.
