Portfolio
Xavier Briggs
A solo engineer who designs, builds, and maintains production systems. Notre Dame CS student, returning Amazon Prime Video intern, and freelance owner-operator.
- Amazon Prime Video - returning SDE intern
- Freelance owner-operator - TLC's production stack
- Forecasting and trading systems - FORTUNA and Aeolus, built solo
Project 01
in production, 3 properties
TLC
Sole engineer behind a manufactured-home finance company's production stack: I designed, built, and run its three web properties, 11-person CRM, and lead funnel. Monthly inbound leads grew about 5x (~20 to ~100).
Three production properties - a borrower site, a 197-dealer portal, and an 11-person CRM - run on TypeScript, React/Next.js, Firebase, and Supabase/Postgres, backed by a Twilio-based voice intake agent.
Inbound leads · per month
~20grew to~100
before the funnelafter
5x growth in monthly inbound leads, funnel built end to end
3 web properties designed, built, and operated solo
- Borrower site
- ~2,500 monthly visitors
- Dealer portal
- 197 dealers on the network
- Internal CRM
- 11 person team, daily use
- Voice intake agent
- answers, qualifies, and hands borrower calls to the CRM
TypeScript · React · Next.js · Firebase · Supabase/Postgres · Twilio ConversationRelay
Read the case studyProject 02
commercially launched, operating
Aeolus
A 26-station temperature-forecasting API. Statistical calibration cut forecast error 45% (CRPS 2.25 to 1.23), and it runs unattended at 99.8% daily reliability.
EMOS statistical calibration corrects GEFS ensemble output station-by-station, cutting forecast error (CRPS) 45% through iterative recalibration.
CRPS · forecast error, lower is better
2.25raw GEFS ensembledown to1.23after EMOS calibration
45% forecast-skill improvement, verified before live deployment
- calibrated forecasts issued
- 20,000+
- automated daily success rate, unattended operation
- 99.8%+
- stations covered by the forecasting API
- 26
Python · GEFS ensemble data · EMOS calibration
Read the case studyProject 03
shadow mode, 0 live trades, by design
FORTUNA
An autonomous prediction-market trading platform that forms its own calibrated probabilities and runs every decision through layered GO/NO-GO gates. 3,400+ trade decisions evaluated in shadow mode.
Three independently operating systems - Alexandria, Pythia, FORTUNA - enforce seven regulatory-inspired invariants in code so no system grades its own output.
- Alexandriaincorruptible data witness
- Pythiabelief formation
- FORTUNAjudging and execution
- no system grades its own output
- shadow-mode trade intents evaluated
- 3,400+
- regulatory-inspired invariants enforced in code
- 7
- independent systems, none grades its own output
- 3
- calibrated-probability pipeline, every fetch logged and hashed
- 5-stage
Python · Rust · Postgres · Anthropic API · Kalshi API
Proof from the field
What the work moved.
5xInbound leads
monthly leads, before and after (~20 -> ~100/month)
- 3Production properties
- web properties designed, built, and operated solo
- 197Dealer network
- dealers served by the portal
- 11CRM team
- person internal team using the CRM
- LiveVoice agent
- production voice intake agent answering inbound borrower calls
About
The path behind the work.
Education
- University of Notre DameMay 2027Notre Dame, IN
B.S. Computer Science and Engineering, ITREDS Scholar - GPA 3.91
- University of GalwayJan 2026 – May 2026Galway, Ireland
Study abroad - First Class Honours in all coursework
Experience
- Amazon Prime Video - Apple Player TeamMay 2026 – Aug 2026Software Development Engineer Intern (returning) · Seattle, WA
Productionizing a tvOS media playback feature toward general availability, owning concurrent multi-player support across Swift, SwiftUI, and AVKit.
- Amazon Prime Video - Apple Player TeamMay 2025 – Aug 2025Amazon Propel Intern · Seattle, WA
Built a tvOS media playback feature from scratch across 4 phases, 10+ merged reviews with zero regressions, and cut Team Knowledge Agent context usage from 12% to 5%.
- TLC Manufactured Home Finance Consultants2024 – PresentLead Developer (Freelance, Full-Stack) · Remote
Sole engineer for three production web properties and an 11-person CRM; grew inbound leads ~5x and shipped a Twilio-based voice intake agent.
- Tweeds - Personal Publishing PlatformJan 2025 – May 2025Backend Developer · South Bend, IN
Built RESTful controllers powering Gemini-driven content analysis and a manuscript-to-marketing generation pipeline.
Leadership & programs
- ColorStack at Notre Dame · President
Leads a 25-member chapter for underrepresented CS students, running 5 events a semester.
- CS4Good · Treasurer (previously President)
Led 8 community software projects for assistive schools, community centers, and nonprofits.
- Management Leadership for Tomorrow · Career Prep Fellow
Selected into an 18-month professional development program for high-achieving diverse talent.
- AI4All Ignite · Changemaker
Built an end-to-end deepfake speech detector (81.5% accuracy), presented at the Ignite symposium.