Sergei Garcia
I'm a senior software engineer with 10+ years building user-facing products, strongest on the front end and comfortable well past it on the server side. Most recently I spent a few years eliminating the language barrier at Reddit across 41 languages and millions of users which was a lot of fun. I came into engineering through design, which is why I tend to argue about what we're building before I argue about how, and why I'm the person who most quickly notices the page got slower. Caring that much is contagious, which is mostly how I end up teaching. It turns into the tool the team uses daily, or the AI course I wrote for people who don't write code, because the interesting problem now isn't getting AI to produce code, it's knowing what to trust and how to prove it, and that's a thing you teach. Teaching is the part I'd do for free. Open to senior front-end, full-stack, product and DX roles: remote from Mexico (Mexican citizen, no sponsorship needed) or in Ireland with an employment permit.
REVIEWS FROM CLIENTS
- Owned the web experience for LLM-translated user-generated content at Reddit, the surface behind the company's largest internat...
- Owned the web experience for LLM-translated user-generated content at Reddit, the surface behind the company's largest international growth results of 2024 to 2026: spanning 41 languages and reaching tens of millions of daily users. Redesigned it from the ground up: translation indicators, language controls, multilingual reading, compact view, and the exposure and telemetry layer under all of it.
- Re-architected English translation delivery to render server-side, cutting up to 250ms of dead client code for the 90% of users who never see a translation.
- Built the server side of new features in Reddit's in-house server-rendering framework: consuming GraphQL endpoints, request middleware, partial-page endpoints and server-to-client data flow, plus BigQuery SQL to measure results.
- Agentic development and verification. Built AI code-review personas that carry domain expertise onto every change, code-quality rules that catch tests passing while the product is broken, and agentic browser verification powered by Playwright End-to-End browser testing suites.
- Built developer tools now used across Reddit engineering, one in the code editor and one in the browser, replacing error-prone manual setup with one click: targeting test runs, reproducing an exact experiment or user state, seeing what the server rendered, and handing a working setup to a teammate.
- People multiplier and mentorship. I onboarded every front-end contractor who joined after me, with consistently positive feedback, and wrote the domain guides both new engineers and AI agents learn the system from. I've extended that company-wide with an AI fluency course built to make people productive with agentic workflows while spending less on models, and I'm now moving it from hosted resource to taught sessions.
- Project #1 St. Jude Children's Research Hospital (2025): brought in as the only front-end engineer across 3 projects:
- S...
- Project #1 St. Jude Children's Research Hospital (2025): brought in as the only front-end engineer across 3 projects:
- St. Jude Cloud: built the new website from scratch in Nuxt, Vue and Tailwind, with a design system from the Figma designs and a lightweight JSON-driven CMS (block-based page renderer, generated announcement and publication pages with filters and pagination). Ran accessibility (screen reader, contrast) and Lighthouse performance rounds.
- Sprocket, St. Jude's open-source genomics workflow engine: redesigned the sprocket.bio site and overhauled its Rust-generated documentation by untangling the templates, adding a themeable design system with reusable components and a light mode, and fixing long-standing layout bugs.
- LearnGenomics.dev: rebuilt and redesigned the learning site on a Next.js/MDX documentation template, fixing its bugs, accessibility and usability.
- Project #2 Northeastern University, College of Engineering (2023 to 2024): Built the React, TypeScript and Tailwind front end of an AI product-research app for footwear and apparel brands: sentiment-analysis dashboards, a concept-evaluation flow and a ChatGPT-powered assistant. Set up hosting on AWS S3 and organized the team's planning to hit an MVP demo deadline.
- Project #3 Marmalade (2024): New components, banners and layout redesigns for an AI-driven discovery platform for independent brands (Next.js, TypeScript, Tailwind, Apollo GraphQL).
- Project #4 AquascapeAI (2024): Built the front end of an AI aquarium-design generator from scratch (Astro, React, Tailwind, Vercel), including a reusable, keyboard-accessible form component library.
- Led the modernization of two Typing.com products: the teacher portal and internal customer-service dashboard. Rebuilt their front en...
- Led the modernization of two Typing.com products: the teacher portal and internal customer-service dashboard. Rebuilt their front ends with React, Tailwind, and Headless UI while working alongside an existing PHP/Laravel backend. The teacher-facing work was part of a platform serving 35M+ monthly users.
- Guided a front-end developer and a designer/developer through the work. Turned a prolonged disagreement over the teacher portal's React architecture into an agreed direction by presenting the trade-offs and working through them with leadership.
- Designed a GraphQL API architecture proposal for the React Admin migration, with a working demo and risk analysis to evaluate the approach.
- Used Shape Up to turn complex stakeholder requests into manageable work, with clear updates that helped people understand project decisions and challenges.
- Established a PR process, issue triage, and a shared design-system component library. Mentored colleagues and helped the team build more consistent front-end practices.