Software Engineer focused on AI-enabled products, conversational systems, and modern web applications.
I build at the intersection of software engineering, AI, product thinking, and real-world operations.
I have 5+ years of experience building production software, with a foundation in React, TypeScript, APIs, integrations, and product-focused frontend engineering.
More recently, my work has expanded into Conversational AI and Prompt Engineering, where I work with OpenAI APIs, prompt and context design, structured outputs, intent classification, routing logic, tool/function calling, and human-in-the-loop workflows.
At ChatSasa, I’ve contributed to an AI-assisted omnichannel customer-support platform spanning WhatsApp, SMS, email, and web chat, working across AI workflows, agent experiences, APIs, dashboards, integrations, and operational tooling.
AI & Conversational Systems OpenAI APIs · Prompt Engineering · Context Design · Structured Outputs · Guardrails · Tool / Function Calling · Intent Classification · Human-in-the-Loop Workflows · AI Evaluation
Software Engineering JavaScript · TypeScript · React · Next.js · REST APIs · GraphQL · PostgreSQL · JSON
Product & UX User Flows · Product Requirements · UI/UX · Prototyping · Product Thinking · Agile/Scrum · Stakeholder Collaboration
Delivery & Engineering Practices Testing · GitHub Actions · CI/CD · API Integration · Technical Documentation · Debugging · Production Troubleshooting
A public engineering portfolio exploring practical prompt engineering and LLM application workflows, including prompt architecture, structured outputs, intent classification, guardrails, human escalation, evaluation, versioning, and reliability considerations.
🔗 https://github.com/williamOnsare/conversational-ai-prompt-lab
AI-assisted omnichannel customer-support platform spanning WhatsApp, SMS, email, and web chat, combining conversational AI, human supervision, messaging integrations, routing, operational dashboards, and agent workflows.
Production implementation is maintained in a private codebase. Architecture, workflows, and non-confidential technical patterns can be discussed without exposing proprietary code or customer data.
Developer utility focused on mobile-money verification workflows, structured API data, validation, and troubleshooting UX.
🔗 https://mpesa-hash-decoder.vercel.app
Marketplace prototype exploring product discovery, onboarding, booking workflows, and conversion-oriented user experience.
🔗 https://podoa-plus.vercel.app
An entrepreneurial venture I co-founded and continue to operate, providing hands-on experience across product decisions, customer experience, supplier coordination, pricing, operations, problem-solving, and continuous improvement.
🔗 https://www.google.com/search?q=coolato+creamies
I’m interested in technology that solves practical problems rather than technology for its own sake.
I enjoy taking ambiguous requirements, understanding the underlying problem, designing a workable solution, and iterating based on real-world feedback.
My approach combines:
Engineering depth → understanding how systems actually work AI experimentation → exploring where AI can improve workflows and decision-making Product thinking → focusing on users, outcomes, trade-offs, and usability Operational ownership → understanding what it takes to make solutions work beyond the code
AI Engineering · Management Roles · Prompt Engineering · AI Product Development · Technical Product Roles · Product Engineering · Software Engineering · Digital Product & Project Delivery
📍 Nairobi, Kenya
🌐 https://williamonsare.vercel.app
💼 https://www.linkedin.com/in/williamOnsare
🐙 https://github.com/williamOnsare
I’m always interested in building useful products, exploring emerging AI capabilities, and collaborating on problems worth solving.