Simplex, a technology partner specializing in consulting, systems development, and operations, has deployed OpenAI's Codex across its organization after quantitative evaluation showed significant productivity gains. The company adopted ChatGPT Enterprise as its foundation and selected Codex as its primary coding agent, moving beyond experimentation to operational AI-native delivery.

The company tested Codex on CRUD-based web applications and measured concrete results: 40% fewer hours for screen design, 70% fewer hours for screen development, and 17% fewer hours for internal integration testing. Executive Principal Kazuya Ujihiro noted that Codex enables smaller teams to advance design work and improves specification review accuracy across multiple files.

Simplex is fundamentally redesigning its development process rather than simply automating individual steps. Rather than following a linear sequence of requirements, design, implementation, testing, and operations, the company now defines rules and constraints up front, then improves quality through repeated integration and automated evaluation. Ujihiro sees a future where, as databases, API catalogs, and standardized design rules mature, Codex could take on much of the implementation and validation work.

The company recommends that organizations validate AI impact quantitatively before production use, treat adoption as an operating model with governance and training, choose a primary AI agent to build concentrated expertise, and clearly separate where AI executes work versus where humans retain final accountability.