Blitzy, founded in 2023 in Cambridge, Massachusetts, runs more than 3,000 specialized agents against an entire codebase, up to 100 million lines, to plan and generate large-scale changes, positioned directly against Claude Code and Codex as an enterprise alternative built for scope rather than speed.
Its process runs in six stages: ingesting and mapping the full codebase, generating a technical specification of the existing architecture, taking a natural-language prompt for what to build, producing a detailed Agent Action Plan for a team to review and approve before any code generates, then running autonomous generation for 8 to 12 hours of extended reasoning, producing up to 3 million lines of pre-compiled, tested code. The company reports the platform completing around 80% of a roadmap or new product autonomously, with a human engineering team finishing the remaining 20% for production.
Blitzy includes a free tier for requirements and technical-specification generation, with full autonomous development sold as an enterprise contract rather than self-serve. For an enterprise team modernizing a large, legacy codebase who wants a reviewed, pre-validated plan executed over hours or days, rather than an interactive coding session, Blitzy's extended-reasoning, full-codebase approach addresses that directly.






