Liam McCartney

Builds dependable software inspired by the people it serves and the work they do. Mentors engineers and creates technical foundations that teams can understand, evolve, and trust. Husband to Katie and dad to Cillian based in Long Island, NY.

Experience

Fulcrum — Lead Software Engineer — Minneapolis, MN (Remote)

Oct 2020 — Jul 2026

Early engineer promoted from Senior to Lead as the company grew. Led architecture for software powering manufacturers’ operations, set frontend technical direction, and managed and mentored engineers.

C# · ASP.NET Core · Entity Framework Core · SQL Server · Azure · Angular · TypeScript

Rebuilt inventory tracking as an event-sourced ledger, replacing an opaque mutable count with a replayable, repairable system processing millions of events.
As sole engineer and product owner, built an end-to-end shipping system leveraging the inventory ledger, spanning UI, backend, and legacy migration. Partnered closely with customers throughout beta and led rollout across the customer base.
Led delivery of a canonical materials database for sheet-metal and CNC manufacturing, enabling cross-job nesting, geometry-aware purchasing, and more accurate estimating, costing, and inventory.
Defined architecture and standards across the Angular codebase; introduced NgRx through a shop-floor rewrite that eliminated recurring stale-state bugs and established shared state management.
Managed four engineers and led a six-person frontend team, setting priorities, delivering feedback, and mentoring early-career engineers into independent contributors.

CourseHorse — Full Stack Software Engineer — New York, NY

Aug 2018 — Oct 2020

Worked alongside the CTO and VP of Engineering on a three-person team building and operating a class discovery and booking marketplace.

PHP/Zend · CakePHP · Elixir/Phoenix · React · Solr

Partnered with Google to implement "Reserve with Google," enabling users to book classes directly from Google Maps and Search via the Phoenix API.
Built CourseHorse Groups, a private group-event discovery & booking product, owning search functionality across the entire stack.
Tuned the Solr index behind class discovery, reworking filtering and result-query scoring for more relevant and reliable results.

Success Academy — Software Developer — New York, NY

Feb 2015 — Aug 2018

First software developer on staff; helped launch the Technology Department and modeled business processes into code.

C# · Angular · AWS Lambda · Python/Flask · SQLAlchemy · Docker · Jenkins

Built the Scholar Information & Enrollment Suite, a network of serverless services and web clients capturing student and guardian data alongside a legacy application; led the team's migration to Angular 2 and owned CI/CD.
Owned an extensible validation framework for the Middle School Scheduler, absorbing rapidly changing business rules; contributed to the design of the schedule-generation algorithm it validated.
Sole developer of Magnus, a data visualization dashboard tracking student performance, growth, and behavior.

Selected Project

Cuttyhunk Yacht Club Registration — Creator & Software Engineer

app.cuttyhunkyachtclub.com

2026 — Present

Elixir · Phoenix LiveView · PostgreSQL · Square Checkout API · Fly.io

Built and launched a custom membership, donation, and class-registration platform after off-the-shelf tools failed to fit the club’s workflows; supported 200 members and 300 registrations in its first season.
Partnered directly with the club board and its appointed technical lead on product discovery and design; now own development, Square integration, deployment, and operations.