Senior Software Engineer · Frontend Architect

Frontend architecture
for products that
need to scale.

I'm Tymek — a senior frontend engineer with 8 years of experience building complex, high-traffic systems. I specialize in architecture, React, and design systems that teams actually want to work with.

Available for engagementsRzeszów, Poland · WorldwideCHARTCODE
8+Years of experience
20+Products shipped
5M+Users served
Lines of code
Expertise

Where I focus my work

Eight years of depth across frontend engineering, architecture, and technical leadership. Not a generalist — a specialist who knows where the hard problems live.

Frontend Architecture

Structural decisions that hold up under real scale. Module boundaries, data flow, dependency management — designed to last.

React & TypeScript

Component design, performance patterns, type safety across large surfaces. Not just working code — code that doesn't become a problem six months later.

Design Systems

Building the foundation teams build on. Token systems, component APIs, documentation, tooling — systems that accelerate rather than constrain.

Performance

Measured, targeted optimization. Bundle analysis, rendering strategy, Core Web Vitals — with direct impact on user experience and business metrics.

Technical Leadership

Engineering standards, code review culture, architectural direction. Building environments where good engineers do their best work.

Product Engineering

Enough product and UX context to make the right tradeoffs. The gap between "works" and "right" is where this matters most.

AI Product Engineering

New focus area

Building the frontend layer of AI-powered products. Streaming interfaces, LLM API integration, real-time inference UI — and the structural patterns that keep AI features maintainable as models evolve.

Services

How I engage

Focused engagements, defined scope, real outcomes. I work with a small number of clients at a time to ensure full attention and quality.

Architecture Review

An honest assessment of your frontend codebase. I identify structural risks, performance bottlenecks, and maintainability problems — with a clear path forward.

Written report + recommendations

Embedded Engineering

Working directly within your team on complex frontend problems. Not advisory — hands-on. I write code, lead architecture decisions, and raise the technical bar.

Ongoing, typically 3–6 months

Design System Build

From token infrastructure to component library to documentation. Built for your team's workflow, not a generic reference implementation.

Component library + documentation

Performance Audit

Deep diagnosis of rendering bottlenecks, bundle bloat, and Core Web Vitals issues. Prioritized by actual user impact, not just Lighthouse scores.

Audit report + implementation plan

AI Feature Integration

Taking your AI capabilities to the product surface. Streaming responses, tool-call UIs, structured output rendering, loading states that don't feel broken — the frontend work that makes AI features feel polished rather than bolted on.

Feature build + architecture
Start a conversation

Custom engagements available for larger scope

AI Engineering

I build the frontend layer
of AI-powered products.

Discuss your AI project

Streaming interfaces

Token-by-token streaming with graceful loading states, partial renders, and error recovery. Users feel the speed — even when the model is slow.

LLM API integration

Clean abstraction layers over OpenAI, Anthropic, and open-source models. Prompt management, retry logic, and structured output parsing that doesn't leak into component code.

AI-native UX patterns

Chat interfaces, copilot sidebars, inline suggestions, tool-call visualizations. Patterns that feel native — not retrofitted from a non-AI product.

Maintainable as models change

AI product frontends that don't break when you swap providers or upgrade a model. Architecture decisions made with that volatility in mind from day one.

Works with: OpenAI · Anthropic · Vercel AI SDK · open-source models

Selected Work

Problems I've solved

A selection of complex engineering work. Names withheld under NDA — details available on request.

01

U.S. Enterprise E-commerce Platform

Cooperated with a U.S. team on rewriting an e-shop for one of the largest office supplies providers in the United States — used by 300,000 companies and millions of end users, with over 1,000 concurrent visitors at peak. The core challenge: the platform is highly customizable per customer, with independently configured product catalogues, pricing, and availability. Building for that level of variability required disciplined architecture from the start.

ReactTypeScriptE-commercePerformance
02

iOS & Android App — 2M+ Downloads

Worked with a Swedish engineering team on a mobile app with over 2 million downloads. Contributed new features, built reusable internal components, and participated in product and technical decision-making. Focused on performance optimization and maintainability — including pair programming sessions to share patterns across the team.

React NativeiOSAndroidPerformance
03

Technology Audit & Stack Decision

Conducted a comprehensive technology audit for a product team standing at an architectural crossroads. Evaluated competing approaches, frameworks, and tooling choices against the team's actual constraints — scale expectations, delivery timeline, and maintenance capacity. The recommendations directly influenced the technology decisions made, saving significant time and budget that would have been spent building on the wrong foundation.

ArchitectureTech AuditConsulting
04

AI-Powered Knowledge Platform

Built the frontend of a B2B knowledge platform with LLM-powered search, streaming chat, and structured document generation. Architected the AI feature layer — streaming responses, tool-call visualizations, and fallback handling — keeping it maintainable as underlying models and providers evolved.

AI SDKStreamingReactTypeScript
Stack

Technologies I work with

Built over 8 years of real-world usage. Each tool chosen for a reason — not resume-padding.

Core
React
TypeScript
Next.js
State & Data
Redux
RxJS
React Query
Styling & UI
Tailwind CSS
CSS Modules
Storybook
Mobile
React Native
Expo
Native iOS/Android
Tooling
Vite
Webpack
ESLint
AI & LLM
Vercel AI SDK
OpenAI SDK
Anthropic SDK
Why work with me

Seniority is about
what you don't
have to explain.

I work best with teams that want a senior engineer who takes ownership — not a contractor who needs hand-holding.

Ownership, not task completion

I take responsibility for outcomes, not just my assigned work. If something adjacent is wrong, I say so.

Systems thinking

I design for the fifth feature, not just the first. Decisions made early determine what's possible later.

Honest communication

No overpromising. If a deadline is unrealistic or an approach is flawed, you'll hear it from me — clearly and early.

Product awareness

I understand why decisions matter, not just how to implement them. This changes the quality of the tradeoffs I make.

Clean, reviewable code

Code I write is easy to read, easy to extend, and easy to delete when requirements change.

Deep frontend knowledge

Eight years of working on hard frontend problems — architecture, performance, systems — not just shipping features.

About

Tymoteusz Tracz

Frontend Architecture & Engineering

Rzeszów, Poland · Worldwide

I've spent the last eight years building frontend systems for products that couldn't afford to get it wrong. E-commerce platforms, SaaS tools, financial applications — the kind of work where performance, reliability, and long-term maintainability are real constraints, not aspirations.

For the past few years I've been operating as Head of Frontend Guild — setting engineering standards, leading architecture reviews, and growing teams. I've seen what separates codebases that age well from ones that become liabilities.

I started CHARTCODE to work directly with companies that want to raise their frontend bar. I take a small number of engagements at a time, which means full attention, not divided effort.

Get in touch
Background
2023 — PresentCHARTCODEIndependent consultancy
2025 — PresentHead of Frontend GuildArchitecture, standards, team growth
2020 — PresentSenior Frontend EngineerLarge-scale SaaS & e-commerce systems
2018 — 2020Frontend EngineerProduct engineering, React & TypeScript
Let's work together

Ready to raise your
frontend standard?

Tell me about your project or challenge. I'll let you know whether I can help — and how. No commitment required.

hello@chartcode.eu

I typically respond within 24 hours on business days.

Currently available for new engagements