Alistair Pullen

Alistair Pullen co-founded Cosine in 2022 alongside Yang Li, both Cambridge PhDs, and serves as its Chief Executive Officer. When Cosine was announced as the cornerstone investee of the UK Sovereign AI Fund on 16 April 2026, Pullen articulated the product logic: 'The moment your work touches classified infrastructure, you need an AI that lives entirely inside your walls' . The Sovereign AI Fund secured an option to participate in Cosine's next funding round.

As CEO, Pullen oversees an air-gapped, on-premise sovereign AI coding system that supports 38 programming languages including Fortran and COBOL. Cosine has outperformed OpenAI, Anthropic, Mistral, and DeepSeek on independent coding benchmarks two consecutive years under his leadership.

Pullen's CEO narrative is grounded in deployment reality rather than benchmark performance: Cosine's market is organisations where the risk model prevents using cloud AI entirely. That positions him as building a category — sovereign AI for classified infrastructure — rather than competing directly with general-purpose AI products .