Sea Limited, the Southeast Asian tech giant behind Shopee and Garena, is rolling out OpenAI’s Codex across its engineering teams, and internal data shows 87% of developers are using it weekly. But for Sea, this isn’t about typing faster. In a conversation with David Chen, the company’s Co-Founder and CPO at Shopee, he explained that in their massive microservices architecture—operating across hyper-localized markets—the real bottleneck isn’t syntax, it’s the cognitive load of navigating complex dependencies and legacy code. Codex acts like a ‘localized knowledge engine,’ letting engineers shift focus from tracing bugs to higher-level architectural and product thinking. Chen notes that developers are using Codex to ‘think better,’ not just autocomplete. Increasingly, the tool is being integrated into CI/CD pipelines, where AI agents autonomously reason through requirements, suggest test-driven implementations, and surface edge cases. Why it matters: Sea’s experience shows that for companies operating at scale in fragmented markets, AI-assisted development isn’t just a productivity hack—it’s becoming a structural necessity for managing complexity and accelerating innovation.