ryan w tenney

engineer

I build high-scale distributed systems, routing platforms, and optimization engines. I lead small teams that tackle hard problems and ship fast.

About

I specialize in high-scale distributed systems, routing, and optimization. Over 17 years I've built platforms handling billions of daily requests, led teams that ship fast on ambiguous problems, and found the gaps nobody else was looking for.

I'm at my best leading small, autonomous teams tackling hard infrastructure challenges — real-time routing, dispatch optimization, platform reliability at scale. I like working at the intersection of deep technical problems and business-critical outcomes.

Outside of work, I maintain open-source projects, tinker with hardware, and occasionally build things like constraint solvers for wedding seating charts.

Experience

2018 — 2026

Senior Staff Engineer

Grubhub

Technical lead for Pathfinder, the vehicle routing platform handling 1.5 billion requests per day.

  • Led a team of 5 engineers building real-time traffic, map matching, and drive time polygon services
  • Designed Just-In-Time order dispatch to time kitchen starts based on courier arrival predictions — applied to over 200 million orders
  • Built actor-based simulation modeling realistic order and courier behavior in pre-production, catching bugs that previously went undetected until production
  • Discovered a systemic regulatory compliance violation carrying eight-figure liability across multiple state jurisdictions; implemented geofencing controls to remediate
  • Built MCP servers connecting AI tools to internal systems — self-directed work that spread organically across engineering teams
2016 — 2017

Senior Engineer

American Express

Middleware development for the US cardmember mobile app.

  • Debugged production login failures caused by a race condition that only manifested on Power8 hardware; kept systems running manually during an extended code freeze while tracing the root cause, then shipped a one-line fix
  • Led development of Check Spending Power; uncovered that a dependent team's promised API didn't actually exist, escalated early enough to fall back to a legacy API and ship on time
  • Designed and built mobile backend for Pay It / Plan It, allowing cardholders to pay or finance transactions directly from the app
2013 — 2016

Senior Engineer

EnerNOC

Platform engineering for energy management and demand response systems.

  • Internationalized the entire platform to capture a Japan market opportunity post-Fukushima; designed approach so subsequent locales required no more than 60 days and $60k to support
  • Built tariff engine processing real-time energy readings against a database of global utility tariffs
  • Led engineering team's migration from monolithic webapp to microservices architecture
2008 — 2013

Software Engineer

Shutterstock, Martello Technologies, Symplicity, Xerox

Backend development and systems work across a range of industries.

Projects

01

Wedding Seating Optimization

Demo ↗

Constraint solver that generated the final seating chart for my wedding. Because some problems deserve a proper optimizer.

PythonPuLPFICO Xpress
02

Twomlaut Tour of Germany

Demo ↗GitHub ↗

TSP-optimized road trip visiting every German city with two or more umlauts. MIP formulation with PuLP/CBC, road routing via Graphhopper on OSM data.

PythonPuLPGraphhopperOSM
03

OmniVault

Self-hosted universal file management with full-text search across 1000+ formats, AI-powered enrichment, and complete version history. Think Paperless-NGX with complete file type freedom and integrated AI.

JavaSpring BootReactElasticsearchPostgreSQLDocker
04

Dropwizard Metrics

GitHub ↗

Lead maintainer (2014-2017) of the de facto standard for JVM application metrics. Captures JVM- and application-level metrics so you know what's going on.

JavaOpen Source
7.9k 1.8k
05

USB Battery Minder

Demo ↗GitHub ↗

Custom PCB design for an 8-port USB-C charging station that automatically stops charging at 80% state-of-charge. Detects the CC-to-CV transition in the lithium-ion charge profile to infer battery level without device communication.

KiCadC++ESP32Hardware Design
06

Graph Clearing Problem

Demo ↗GitHub ↗

Solver for a minimax graph clearing problem, built for the ACP Summer School 2018 competition — the only submission within the time limit.

GoConstraint ProgrammingDecision Diagrams
07

Metrics Spring

GitHub ↗

Spring integration for Dropwizard Metrics. Instruments annotated methods on Spring beans through dynamic proxies and bytecode generation. Used by American Express, Apple, Dealer.com, eHarmony, ESPN, Orbitz, and more.

JavaSpringOpen Source
699 224
08

passkit4j

GitHub ↗

Java library for generating Apple Passbook (.pkpass) files.

JavaOpen Source
80 48

Reach out

I'm currently exploring Staff Engineer roles and building out a consultancy practice. Whether you have a hard technical problem, need someone to lead a team, or just want to talk shop — I'd like to hear from you.