Marine engineer. Self-taught developer. Licensed mariner.
Alexander Duff Hughes
Founder · Licensed Mariner
Alex is a licensed marine engineer, former U.S. Navy Reserve officer, and self-taught software developer — a rare intersection of two industries that couldn’t be further apart. Software reinvents itself every few years; maritime has done things largely the same way for centuries. For more than five years, he sailed commercial vessels and helped run operations at The Vane Brothers Company. On the side, he taught himself to code and built Sea Trials from scratch. For five years he ran the whole thing solo — writing every line of code, shipping to every platform, answering every support ticket. Today Sea Trials is better than ever: organized module by module for your exact exam, with an app for every device.
The maritime career
Alex started in the maritime industry when he was just 15 — painting a water barge on the docks for The Vane Brothers Company in Baltimore, Maryland. The next year, he moved into their mechanic shop, rebuilding John Deere diesel engines. By 17, he was out on Vane Brothers tugs and barges — spending his summers in New York Harbor as a deckhand on a 4,200-horsepower towing vessel pushing a 50,000-barrel barge. The following year, he earned his Tankerman Person-In-Charge endorsement, loading and discharging dangerous liquid cargoes before he could legally drink.
At 18, he headed to the U.S. Merchant Marine Academy at Kings Point. He was elected Class President, sailed on commercial and Military Sealift Command vessels around the world, and delivered the commencement address for the Class of 2017.
After graduating with a B.S. in Marine Engineering, a commission as a Navy Reserve officer, and an unlimited horsepower U.S. Coast Guard engineer’s license, Alex began a five-year MARAD sailing obligation, shipping out with AMO as an engineer on tankers. From there he returned to his roots at Vane Brothers, sailing their vessels for years. When the company expanded to Seattle, he moved out there too, splitting his time between helping as a vessel supervisor and sailing on the vessels. He later transitioned to fleet supervisor in New York Harbor — bouncing between the engine room and the office for years, with Sea Trials growing alongside the whole time.
Building Sea Trials
A year into his sailing obligation, on a tanker in 2018, Alex was reflecting on the painful process of studying for the unlimited horsepower license he was now sailing on — and realized USCG exam prep hadn’t moved in decades. Outdated books, zero feedback, no analytics. Half the questions referenced an illustration printed in a separate 500-page volume you had to flip through page by page to find. The moment he stepped off the ship, he started teaching himself to code and built the first iteration of Sea Trials, shipping it while still sailing full-time.
From there he picked up web, then Android, then full-stack development. In an industry as old as maritime, where ships routinely lose signal for days at a time, working offline wasn’t a feature to bolt on — it had to be designed into every layer of the product from day one.
For five years he ran the entire platform solo — development, design, customer support, analytics, everything — while maintaining a full-time maritime career. Sea Trials grew from a side project into a full platform, one module and one platform at a time.
In 2023, Sea Trials shipped an AI tutor built specifically for the USCG exam. That same year, Alex stepped off the boats to focus on Sea Trials full-time.
Sea Trials today
Eight years later, Sea Trials does something we haven’t seen anyone else in mariner exam prep do. Download your library once and the apps work fully offline, then sync when you’re back online. Native on iOS, Android, Windows and macOS, plus the web. Plenty of apps from the biggest names in tech stop working the moment you lose signal.
Most apps stop working the moment they lose signal. At sea, that’s most of the time.
Five platforms, one codebase, apps that work fully offline — that has to hold whether a mariner is on Wi-Fi at home or a month into a Pacific crossing. After five years building Sea Trials alone, Alex now runs a team that keeps that promise as the platform grows.
Underneath it all is a custom CI/CD pipeline that ships updates and builds for the App Store, Google Play, the Microsoft Store, macOS, and the web in a single flow, on top of a backend engineered to keep every device in step. Alex oversees the full product lifecycle, from architecture decisions to App Store releases.
Licenses & credentials
- B.S. Marine Engineering & Shipyard Management — U.S. Merchant Marine Academy (Class of 2017)
- Unlimited Horsepower Engineer — Any Ocean (USCG)
- Former LT (O-3) — United States Navy Reserve (Individual Ready Reserve)
- Certified Scrum Product Owner (CSPO)
- Certified ScrumMaster (CSM)
- Tankerman Person-In-Charge — Dangerous Liquids (Barge)
- Refrigeration Transition & Recovery — Universal Certification
Technical skills
Languages & frameworks
Dart, Flutter, TypeScript, Node.js, Swift, React, Next.js, HTML/CSS
Backend & data
Supabase, PostgreSQL, Firebase, Cloud Functions, PowerSync, BigQuery
AI & ML
OpenAI API, Google Vertex AI, Gemini, on-device inference (Gemma/LiteRT)
DevOps & tooling
GitHub Actions, Codemagic, Melos, Turborepo, Docker, custom Rust CLI tools
Design & product
Figma, UI/UX design principles, user research, A/B testing, analytics-driven iteration
Leadership
Agile/Scrum, team management, technical architecture, cross-functional coordination
The journey
From painting water barges at 15 to building the USCG exam app he wished he’d had.
- Age 15
First job at Vane Brothers
Started painting a water barge on the docks for The Vane Brothers Company in Baltimore, Maryland. The next year, moved into the mechanic shop and learned to rebuild John Deere diesel engines.
- Age 17
Out on the boats
Spent his summers working on Vane Brothers tugs and barges in New York Harbor — a deckhand on a 4,200-horsepower towing vessel pushing a 50,000-barrel barge. Earned his Tankerman Person-In-Charge endorsement the following year, loading and discharging dangerous liquid cargoes before he could legally drink.
- 2013
Headed to Kings Point
Graduated high school after leading the robotics team. Accepted into the United States Merchant Marine Academy — Marine Engineering & Shipyard Management.
- 2013–2017
U.S. Merchant Marine Academy
Elected Class President. Sailed on commercial and Military Sealift Command vessels around the world. Wrote his first real code — Python ship trackers — during a summer internship at a defense contractor.
- 2017
Graduated & commissioned
Graduated with a B.S. in Marine Engineering, delivered the commencement address, and commissioned as a U.S. Navy Reserve officer. Began a five-year MARAD sailing obligation with AMO as an engineer on tankers.
- 2018
Founded Sea Trials
USCG exam prep had no modern technology — outdated books, zero feedback, no analytics. The moment he stepped off the ship, he started teaching himself to code and built the first iteration of Sea Trials, shipping it while still sailing full-time.
- 2018–2023
Sailing, Vane Brothers & Sea Trials
Sailed as an engineer with AMO on tankers, then returned to Vane Brothers, sailing their vessels for years. When the company expanded to Seattle, moved out there too — splitting time between helping as a vessel supervisor and sailing on the vessels. Later transitioned to fleet supervisor in New York Harbor, bouncing between the engine room and the office while Sea Trials kept growing alongside.
- 2023
Built an AI tutor that knows the USCG exam
Shipped an AI tutor built specifically for the USCG exam, with a clear, step-by-step explanation for any question. That same year, stepped off the boats to focus on Sea Trials full-time.
- 2023–2026
Organized around your exam
Grew Sea Trials into a full platform for 55 Coast Guard licenses and ratings, organized module by module for each individual test, with native apps on every device. Built out a team of engineers.
- 2026
Native everywhere, at scale
Sea Trials runs natively on iOS, Android, Windows and macOS, plus the web — apps that work fully offline and sync when you’re back online, shipped from a single codebase. A team of engineers in place to build the next decade of mariner education.


