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Ruben Rajkowski

Senior Full-Stack Engineer

Los Angeles, CA · Kalispell, MT

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Summary

Solution-oriented full-stack software engineer with 12+ years designing, building, and maintaining scalable backend systems and web applications across streaming media and advertising technology. I build high-performance APIs, distributed systems, and microservices with Node.js, Go, React, and AWS, own services end to end including on-call, and work directly with ad ops, QA, and product to deliver reliable software.

How I work

I'm a dad, husband, and coder. I work remotely from my home office and keep a real line between work and home. Most of my week is heads-down building, with some meetings and mentoring mixed in, and agentic coding tools help me move faster.

I want a role where I stay in the architecture and the build, with room to be creative rather than mostly reviewing code. I'm open to full-time or contract if the fit is right.

Experience

  1. Staff Software Engineer

    Feb 2024 – Present

    NBCUniversal, Inc. (Peacock) · Universal City, CA - Remote

    • Designed the Node.js ad-delivery config service (VAM): an OpenAPI contract and one data model shared by header bidding, experiments, VOD, live, and linear. 10,000+ TPS at p50 ~20ms, p95 <1s peak vs a 2s round-trip SLA, with 99.99% uptime, and I was on-call for incidents. Other teams build on it instead of forking config. Shipped a React UI on top, with Azure SSO.
    • Assisted with the Go rewrite of that service (ACE) and owned the A/B testing and Amazon APS header bidding modules: p50 ~10ms, p95 ~100–200ms typical. Also own two Go microservices on the same path: CDN steering, and asset-metadata ingest over Kafka.
    • Design knowledge systems and feature pipelines that ground model output in production data for targeting, analytics, and internal tooling. The product question is cost, relevance, and whether the answer matches the source.
    • Ship with Cursor (IDE and agents). I still own the contract, the failure mode, and the merge.
    • Production on Kubernetes (EKS) in AWS: scaling, multi-region, monitoring. Set direction across a matrixed org without a team under me.
  2. Senior Software Engineer

    Jun 2020 – Feb 2024

    NBCUniversal, Inc. (Peacock) · Universal City, CA - Remote

    • Owned Video Ad Manager v1 for the Peacock launch. Node.js services in front of the live and VOD ad path, split into microservices so a bad deploy did not take the whole break with it.
    • Held the on-call path for NFL Playoffs and the Olympics. High-traffic nights meant no-fill spikes and latency in the middle of a game, traced in production and fixed before the next break.
    • Those sessions ran late. The work was the live event, not a ticket queue. The same platform now serves ~9B ad impressions a month across Peacock, NOW TV, and SkyShowtime, with 10k+ TPS of live traffic at Olympics and NFL peaks.
    • Left the v1 contracts in a shape the Go rewrite could take over: one config model, explicit APIs, and services other teams were already calling.
  3. Senior Software Engineer

    May 2017 – Jun 2020

    NBCUniversal, Inc. · Universal City, CA - Hybrid

    • NBCUniversal ad platform, before Peacock. Owned solution architecture for Ad Manager v1 on AWS. Serverless services and DynamoDB behind real-time bidding across FreeWheel, Amazon header bidding, and Roku. Splunk for no-fill and latency. Prometheus and Splunk alerts. OpenAPI standards and SAML/OAuth plugins other teams adopted.
  4. Senior Frontend Developer

    Feb 2014 – May 2017

    NBCUniversal, Inc. · Universal City, CA - On-site

    • Built display-ad delivery on Google Ad Manager and Google's ad APIs for high-traffic NBCU properties including NBCNews.com and Fandango.com. Owned campaign setup and delivery screens in the internal ad CMS (PHP, JavaScript, SQL), plus the SAML and OAuth path into the tool.
    • Built the JavaScript client authentication for NBCUniversal MediaVillage (nbcumv.com), NBCU's media-sharing platform, still in use today.

Additional Experience

  • Senior Front-End Engineer, Dex Media, Inc. | Santa Monica, CA
  • Co-Founder & Software Engineer, Breaking Development | Greater Los Angeles Area
  • Web Developer (contract), JAKKS Pacific | Malibu, CA

Selected Projects

  • RagePicks | ragepicks.com: Built solo an AI sports-analytics app with Python, FastAPI, Supabase, and a multi-model LLM pipeline.
  • Turbine Workforce | turbineworkforce.com: Contract engineer building the backend for an AI workforce and compliance platform, including Node.js and Python APIs for retrieval-augmented generation (RAG) over company documents and vector search on Supabase (PostgreSQL with pgvector).

Education & Credentials

  • Bachelor of Science in Computer Science, The Master's University, Santa Clarita, CA
  • Claude Code in Action - Anthropic / LinkedIn Learning, 2026
  • Build 10 AI Agents with Claude Code & Claude Cowork - Udemy, 2026

Awards & Recognition

  • 2025 Webby Award - Apps & Software: Entertainment & Sports : Team award for Peacock's 2024 Paris Olympics streaming experience; owned the ad-delivery service and provided on-call support during the Games.
  • 2025 Sports Emmy Award - Outstanding Interactive Experience : Team award for Peacock's Paris 2024 Olympics interactive experience on NBC and Peacock; contributed to ad delivery supporting peak traffic.

Technical Proficiencies

Languages

TypeScript JavaScript Node.js Go Python SQL

Frontend

React Redux Toolkit MUI Vite Vitest Tailwind

Backend & APIs

REST OpenAPI Microservices Distributed systems Event-driven design Kafka Google Cloud Pub/Sub OAuth2 SAML Azure SSO

Data

PostgreSQL MongoDB DynamoDB Couchbase BigQuery

Cloud & DevOps

AWS Kubernetes Helm Argo CD Docker CI/CD Prometheus Splunk Sentry On-call

Ad Tech & Streaming

Connected TV OTT devices Live streaming AWS MediaTailor FreeWheel Google Ad Manager Header bidding Optimizely A/B testing

AI Tools

Cursor Claude Code RAG LLM APIs