Hi, my name is
Omar Contreras
Backend Software Engineer
Building production-quality systems with AI-augmented engineering practice. Payment infrastructure background at Twilio. Currently shipping open-source tools for AI conversation analysis, multi-agent orchestration, and personal data systems.
Available for senior backend & AI engineering roles — reach out on LinkedIn.
01 / About
About Me
I'm a software engineer with experience building payment systems at scale, SaaS platforms, and AI-powered tools. At Twilio, I worked on payment processing infrastructure handling millions of transactions, earning a promotion to L2 Software Engineer.
My background spans distributed systems, API design, and full-stack development. More recently, I've been exploring AI agent architectures and building open-source tools for conversation parsing and knowledge orchestration.
- Location
- San Francisco, CA
- Focus
- Distributed Systems, Payment Platforms, AI Agents
- Languages
- Python, Java, Scala, TypeScript
02 / Experience
Where I've Worked
2024 — Present
Independent Engineering Practice
Open-Source Software & AI-Augmented Engineering
- Focused on AI-augmented engineering at production quality
- Shipped four open-source systems totaling 15,000+ tests across Python and Java
- Developed a constitutional engineering framework with multi-tier sub-agent review enforcing strict typing, modular architecture, and comprehensive coverage on AI-collaborated code
2019 — 2023
Twilio
Software Engineer (L1 → L2)
- Built and maintained payment processing systems handling millions of transactions
- Promoted to L2 for impact on billing infrastructure and cross-team technical leadership
- Worked across Scala, Java, and Python services in a distributed microservices architecture
- Contributed to API design and developer experience for payment integrations
2024
Panoculum
Software Engineer (Contract)
- Migrated mobile application from React Native to React for web platform
- Full-stack development with modern JavaScript tooling
2017 — 2019
DjaoDjin
Software Engineer
- Built sustainability compliance dashboards for PG&E using Django and Vue.js
- Full-stack SaaS development with REST APIs and frontend components
2009 — 2016
UCSF / UC Berkeley
Research Software Developer
- Developed clinical research tools for mental health screening and SMS-based patient monitoring
- Built data collection and visualization platforms used in published research
- Contributed to 5+ peer-reviewed publications in clinical informatics
03 / Projects
Things I've Built
Multi-provider AI conversation parser on PyPI with 2K+ downloads. O(1) memory streaming for 1GB+ files, BM25 ranking with boolean search, and export to Markdown/JSON/CSV. Strict mypy, library-first.
4-agent LangGraph pipeline (Refiner, Critic, Historian, Synthesis) with real LLM integration. WebSocket streaming, FastAPI service layer, hybrid PostgreSQL search, and 6-axis classification routing. 86% coverage.
Local-first YouTube analytics platform with 8,320+ tests across 56 releases. React frontend, FastAPI backend, transcript search, 124K canonical tags, deleted video recovery via Wayback Machine, and Google Takeout ingestion.
04 / Skills