In this talk, I will demonstrate how we leverage LangChain embedded in OBTO's application development platform to create developer agents capable of building and updating end-to-end web applications. OBTO introduces an innovative approach to structuring applications, which, combined with effective prompt engineering and fine-tuned models, significantly enhances the accuracy of these agents. Our platform ensures seamless communication across the tech stack using a unified language, and it incorporates flexible ways to optimize and manage the performance of these interactions. Additionally, OBTO enables continuous feedback loops to refine and improve the agent setups, ensuring a robust and efficient development process.