Sava Lazin — Senior Frontend Engineer

About

Before I wrote code professionally, I worked as a military aircraft technician. That job taught me to build for reliability first.

Over 12+ years in frontend engineering, I've worked on trading platforms, healthcare tools, ad-tech products, and DeFi apps with teams across Europe and the US. Most of my work is in data-heavy interfaces where speed and correctness both matter.

Vue and Nuxt are my core stack, and I've also shipped production code in React and Angular. I usually work on the hard parts: complex state, real-time rendering, and large migrations that need to stay stable while the product is live.

I also care about team systems. I've introduced frontend conventions that became team standards and led migration work that required tight coordination across product teams.

Outside of work, I'm usually reading about aviation, trying new tools, or spending time with my wife and daughter.

What I work with

Tools I use most often

Vue & Nuxt

Core stack. I've led Vue 2 to 3 migrations on live products, built Nuxt 3 apps, and managed Pinia state for real-time features.

Vue 3 Nuxt 3 Pinia Vuex

Data Visualization

Built charting layers for crypto trading and healthcare dashboards. I focus on clarity, performance, and stable real-time updates.

Chart.js ApexCharts TradingView Recharts Highcharts

React & Angular

Shipped React/Redux in DeFi and Angular in ad-tech. I can move across frameworks when the product requires it.

React Redux Angular TypeScript

Performance & Architecture

I focus on component boundaries, predictable state, and rendering paths that stay fast under real traffic.

Vite Webpack Component Design State Management

Styling Systems

I've built with Tailwind and custom systems, set up BEM conventions, and shipped accessible UIs in regulated healthcare contexts.

Tailwind SASS BEM / OOCSS Figma

Domain Knowledge

Most of my experience is in fintech/crypto and healthcare, where UI reliability and data accuracy are critical.

Trading Platforms Web3 / Solana Healthcare UIs Node.js

Selected Work

Projects with clear technical trade-offs and measurable outcomes

Migrating a Live Trading Platform from Vue 2 to Vue 3

Kriptomat had a large Vue 2/Vuex codebase with rising maintenance costs, but a rewrite was too risky on a live EU-regulated exchange. I led an incremental migration to Vue 3 and Pinia, module by module, while product work continued. We moved state first, then upgraded components in dependency order.

Outcome

Completed migration to Vue 3 + Pinia with zero trading downtime for 400,000+ active users
Reduced build times after adopting Vite; Pinia stores were simpler to maintain and test
Delivered migration across the full frontend surface with no feature freeze

Vue 3 Pinia Nuxt 3 Node.js

Building the Real-Time Charting Layer for Crypto Trading

I owned the charting layer end to end for a trading platform with constant WebSocket traffic. The hard part was keeping updates smooth during volatile periods. I used requestAnimationFrame batching and a normalization layer to decouple incoming data from the render cycle.

Outcome

Sub-second chart rendering across portfolio views, trading screens, and market overviews
Unified charting API serving 280+ cryptocurrencies across 1,000+ trading pairs
Smooth UI during high-volatility events under continuous WebSocket streaming

Chart.js ApexCharts WebSockets Vue 3

Healthcare UI with Compliance and Accessibility Constraints

MESI's FDA-cleared, CE-marked diagnostics platform is used by 30,000+ healthcare professionals across 50+ countries. The UI had to be accessible, data-dense, and reliable on desktop stations and tablets. I built reusable components with accessibility built in and worked with design/backend teams to preserve data integrity from API to UI.

Outcome

Compliant, accessible UI shipped and in daily use by 30,000+ clinicians across 50+ countries
Responsive component library handling data-dense diagnostic screens across mobile, tablet, and desktop stations
Part of a platform processing 2M+ measurements annually

Vue 3 Pinia Tailwind Accessibility

Experience

Roles and shipped outcomes

Slovenia, Remote — May 2023 – Sep 2025

Led the Vue 2/Vuex to Vue 3/Pinia migration on a live EU-regulated exchange used by 400,000+ traders across 30+ countries. Delivered it module by module with zero downtime, and owned the charting layer for sub-second real-time rendering with Chart.js and ApexCharts.

Vue 3 Nuxt 3 Pinia Chart.js ApexCharts Node.js

Ljubljana, Remote — Oct 2022 – Apr 2023

Built accessible UI for an FDA-cleared, CE-marked diagnostics platform used by 30,000+ healthcare professionals across 50+ countries. Created a responsive component library for diagnostic workflows and improved collaboration between design, frontend, and backend.

Vue 3 Pinia Tailwind Accessibility

Remote — Dec 2021 – Apr 2022

Built frontend features for a Solana DeFi fund management platform, including wallet flows, on-chain transaction feedback, and portfolio tracking with TradingView charts. Ramped up in the Solana ecosystem quickly and shipped production features within weeks. The platform later wound down during the 2022 market downturn.

React Redux TradingView Web3 / Solana

Copenhagen, Remote — Apr 2021 – Sep 2021

Built the Angular template engine for a dynamic ad platform used by brands like IKEA, Audi, and LEGO in 41 countries. It let non-technical teams compose and preview ad variations and powered high-volume rendering at scale.

Angular 12 Tailwind

Slovenia — Sep 2018 – Jan 2020

Set up frontend architecture and BEM conventions for a crypto custody startup. Focused on high-risk flows involving private keys and multi-step confirmations. The patterns I introduced became the team standard before the company shut down.

Angular 8 BEM Figma

Earlier Experience

Condugo Front End Developer Jun – Aug 2018

Contract role on an EU-funded energy management platform for the petrochemical sector.

ICONOMI Front End Developer Feb 2017 – Jun 2018

Crypto asset management platform with 43K+ users in 161 countries and $327M AUM at peak.

RebelMouse Front End Developer May 2015 – Jul 2016

CMS platform used by publishers including Axios and The Dodo, with 120M+ monthly reach.

Danulabs Lead Front End Developer Aug 2014 – Jun 2015

First lead role, building reusable HTML/CSS templates and jQuery plugins.

Freelance Front End Developer & Designer Sep 2013 – Aug 2014

Worked with international clients via oDesk, DesignCrowd, and 99designs.

Education

Technical School "Mihajlo Pupin"

Electronics — Novi Sad, Serbia

I started tinkering with code in the late '90s with IRC scripts, mIRC bots, and small websites. I moved into frontend professionally in 2013 and have shipped production code across 10+ codebases since.

Let's talk

If you need a senior frontend engineer or migration consulting, feel free to reach out.

Email me LinkedIn GitHub