About
I'm a full-stack engineer. I spent 5.5 years at Wix on the Server Infrastructure team, building the tools 1,000+ Wix engineers used to run and debug their serverless apps.
More recently I brought LLMs into that work: a Slack support agent that answered 60%+ of developer questions on its own, using our docs, code and logs, and an AI reviewer for pull requests. Day to day I build with AI coding agents: Claude Code, Codex, Cursor.
Before Wix, at MEGOGO, I was the first to bring React to the Smart TV app, used by millions of viewers: I led its move off a hand-written vanilla JavaScript UI and designed the React architecture to run fast on low-end TVs. That cut our hiring time for frontend engineers from months to about a week. Earlier: fintech, healthcare-data and consumer web products. Along the way I've led frontend architecture, interviewed candidates and mentored engineers.
Experience
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Senior Full-Stack Engineer, Server Infrastructure Wix
- Designed and built the web app (React, TypeScript, JavaScript, HTML/CSS) that Wix developers used to manage their backend apps: nearly all day-to-day management of 1,000+ apps ran through it. Owned it end to end, UI and UX included, for 2.5 years, and received formal internal recognition for its developer-experience impact.
- More recently, built an LLM support agent in Slack and an AI pull-request reviewer, grounded in internal docs, code and examples through a retrieval-augmented generation (RAG) pipeline, plus service logs. The agent answered 60%+ of developer support questions on its own, and together with a human covered about 95%, since it surfaced the relevant docs and logs.
- Took part in the team's developer-support rotation for the platform's 1,000+ apps: diagnosed failing services in Grafana (logs, metrics, traces) and resolved them hands-on in Kubernetes.
- Added a local run mode to the platform's Node.js CLI: apps now start locally in seconds instead of a minutes-long deploy to production, with production services mocked.
- Added gRPC streaming and Server-Sent Events (SSE) to the serverless runtime and its REST layer, a gap the underlying framework had left open for years; teams needing streaming for LLM features no longer had to switch frameworks.
- Designed type-safe indexing and query APIs for AWS DynamoDB (NoSQL), including custom indexes and queries across multiple indexes.
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Senior Front-end Engineer MEGOGO
- Led the Smart TV app's move from a hand-written vanilla JS UI to React, designing the architecture for the memory, CPU and rendering limits of low-end TVs (Pixi.js, WebGL and Canvas 2D where the DOM was too slow). Frontend hiring time fell from months to about a week: engineers who could build for TVs were rare, React developers were not.
- Built an in-app performance probe that measured, unnoticed by viewers, how the app ran on customers' own TVs. Before, nobody knew which of the millions of viewers would get a laggy UI, a revenue risk; the data let the team ship UI that stayed smooth even on the lowest-end devices.
- Interviewed frontend candidates in a format they repeatedly praised, which helped win strong engineers in a tight hiring market; mentored junior engineers through onboarding, code review and delivery.
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Senior Front-end Engineer Finotec Asia Corp
- Led frontend architecture and implementation decisions as technical owner of a React and TypeScript fintech product.
- Improved code quality through refactoring, code reviews and shared engineering standards; mentored junior engineers through onboarding and feature delivery.
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Front-end Engineer HHS Technology Group
- Built a sports match administration web application from scratch in React and Sass.
- Refactored legacy frontend code on a healthcare data platform, fixing memory leaks and improving performance; delivered investor-demo features for a funding round on a tight deadline.
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Full-Stack Engineer SaveFrom.net
- Implemented geolocation-based routing, affiliate integrations and contextual monetization logic across frontend and backend of a high-traffic consumer web product.
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Full-Stack Engineer TulaCo
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Front-end Engineer MASS Group
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Full-Stack Engineer ART-WEB
- Built and maintained e-commerce sites on a CMS with Sass and Gulp: new features, bug fixes and client support.
Projects
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CS:GO Club community platform
- Volunteer: built and run the platform for a 60+ person community's Friday CS:GO nights, in TypeScript, React, Cloudflare Workers, SQL (D1) and Python. Game servers start on demand and are deleted after each session, so the club pays only for play time.
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Claude Teacher Claude Code plugin
- Open-source AI tutor plugin in Python, JavaScript and Bash that teaches by guiding instead of answering, tracks what the learner knows and quizzes with spaced repetition; 15 GitHub stars.
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claude-profile CLI
- Open-source Bash CLI for macOS and Linux that switches between Claude Code configuration profiles, with Git-based profile history and a bats test suite run in GitHub Actions CI; 12 GitHub stars.
Skills
- AI engineering
- LLM applications, retrieval-augmented generation (RAG), AI agents, Model Context Protocol (MCP), agent plugins, skills and hooks, prompt engineering, AI-assisted development (Claude Code, OpenAI Codex, Cursor)
- Languages
- TypeScript, JavaScript, Bash, HTML, CSS, Sass
- Backend and platform
- Node.js, gRPC, Server-Sent Events (SSE), REST APIs, AWS DynamoDB, Apache Kafka, serverless, microservices, Grafana, platform engineering
- Frontend
- React, Redux, Electron, Pixi.js, WebGL, Canvas 2D, Vite, web performance optimization
- Testing and delivery
- GitHub Actions, CI/CD, Vitest, Playwright, bats, npm, Homebrew, code review, mentoring
Contact
- Emailhi@yarik-leto.com
- LinkedInlinkedin.com/in/yarik-leto
- GitHubgithub.com/yarikleto
- LocationBangkok, Thailand