Hillary Simiyu

Senior software engineer with 7+ years building production-grade apps, AI integrations, and automated testing pipelines. Delivered 60+ freelance projects across Upwork (Top Rated Plus) with 100% job success score. Specialized in LLM-powered apps, full-stack web development, and QA automation for SaaS products. Fast communicator, async-ready, and comfortable leading distributed teams.

Senior AI/Full-Stack Engineer - Freelance · Upwork Top Rated Plus

(2021-01)

• Built RAG-based chatbot for a SaaS client using Lang Chain + GPT-4, reducing support tickets by 42%
• Developed REST API backend in FastAPI serving 500k+ req/day with 99.9% uptime on AWS Lambda
• Delivered end-to-end QA automation suite (Cypress + Playwright) cutting regression time from 8h to 22min
• Integrated OpenAI & Anthropic APIs into 12+ client products across e-commerce, fintech, and SaaS

Software Engineer - TechCorp Inc.

(2018-01 - 2021-12)

• Led migration of monolith to microservices architecture, reducing deployment time by 70%
• Built real-time ML pipeline for fraud detection, processing 2M transactions/day in Python + Kafka
• Mentored 4 junior engineers and authored internal docs adopted across 3 teams

B.Sc. - Computer Science - University of Nairobi (2014-01 - 2018-12)