Buildt

Cosine, operating at buildt.ai, positions itself as a "sovereign AI lab" that trains AI models and specialised coding agents for organisations requiring frontier capability inside secure environments. Its core product line is Lumen, described not as a single model but as a system covering different layers of the software development workflow. The company's stated thesis is that models trained exclusively on real production code from engineering teams outperform generalist models on coding tasks, and that training, optimisation and evaluation decisions are all oriented toward code quality rather than general-purpose capability.

The Lumen family comprises three models. Scout is post-trained from Devstral 123B, runs cheaply and on-device, and handles supporting work around the coding loop. Outpost is post-trained from Kimi K2.6 and targets everyday production software implementation. Sovereign, aimed at frontier-scale reasoning for difficult engineering problems, is listed as coming soon. The models are marketed as producing maintainable, readable, production-quality output rather than bloated code, as able to reason across complex architectures, legacy infrastructure and long-lived codebases, and as post-trained for enterprise and niche languages including COBOL, Fortran, Verilog, Rust and complex SQL.

Users access Cosine through two interfaces: Cosine CLI, a terminal-native interface with a local-to-remote execution model, external tool access via MCP and multi-agent orchestration; and Cosine Cloud, which runs multiple coding tasks in parallel and supports planning large changes and collaboration between engineers, product managers and other stakeholders in a shared project.

Business model

The company offers its Lumen models and Cosine coding tools across tiered deployment options: a fully managed public cloud service for teams that fit standard cloud controls, a managed single-tenant private environment with enterprise controls, and a fully air-gapped deployment that runs inside the customer's own security perimeter. Cloud and self-service entry points sit alongside sales-led routes for the private and air-gapped tiers.

Traction

Publicly available product surfaces include Cosine CLI and Cosine Cloud, both open for sign-up, and the company references operating "in coalition with" partners.