Work experience - Kamil Wierzbicki

IT Architect / Lead Front-End Engineer

2023.02 - Present [3 yrs 10 mos]

I designed the architecture for, and continue to develop, a client application with End-to-End encryption and Blockchain records, ensuring full data privacy and compliance with the highest security standards. I implemented accessibility support (WCAG 2.1) for users with disabilities, optimized the application’s performance and achieved top Core Web Vitals scores for an SPA. Tech stack: React 19, TypeScript 7, TanStack Query 5, MUI 9, Vite 8, i18n, Vitest 4, Testing Library 16, Playwright 1.61.

I delivered a hybrid application based on the existing web client application and published it on the App Store and Google Play. As a result, a single codebase serves the web and native platforms, which lowered maintenance costs and eliminated the need for dedicated native platform teams. Tech stack: React 19, TypeScript 7, Vite 8, PWA, Capacitor 8.

I designed from scratch, and continue to develop, a cryptographic library based on the user’s behavioral pattern. It is the core of encryption and data security for the entire platform. My work covers everything from the API architecture, through performance optimization of cryptographic operations, to integration with the other system modules. Tech stack: TypeScript 7, Node.js 24, WebCrypto, Node-Forge 1.4.

I developed a real-time secret sharing mechanism based on the Elliptic-curve Diffie-Hellman (ECDH) protocol. This increased the security of data exchange between client devices in a real-time architecture (WebSocket). Tech stack: TypeScript 7, Node.js 24, WebCrypto, Node-Forge 1.4, WebSocket.

I designed and implemented the testing strategy for the “Sejf” application, achieving 99% unit and E2E test coverage of business features. I designed automated code quality validation, which made the project fully predictable and stable. Tech stack: React 19, TypeScript 7, MUI 9, Vitest 4, Testing Library 16, GitHub Actions.

I designed and continue to develop an application that verifies documents recorded on the Blockchain: from UI/UX design, through integration with the backend API and the Blockchain, to performance optimization. Tech stack: React 19, TypeScript 7, TanStack Query 5, MUI 9, i18n, Vite 8, Vitest 4, Testing Library 16.

I designed and built from scratch a Whistleblower application, reusing the modular architecture of “Sejf” and ensuring compliance with regulatory requirements. Tech stack: React 19, Next.js 16, TypeScript 7, TanStack Query 5, MUI 9, i18n, Vite 8, Vitest 4, Testing Library 16.

I co-created and continue to develop the product’s cloud architecture, and I am responsible for Infrastructure as Code, deployment automation and architecture monitoring. Tech stack includes: Terraform, GitHub Actions (CI/CD), AWS Lambda, AWS S3, AWS KMS, AWS CloudWatch, AWS DynamoDB, AWS RDS, AWS CloudFront, AWS Route 53, Docker.

I work closely with the business team and the Product Owner on designing key features, translating business requirements into scalable technical solutions in an Agile (Scrum) process.

I ensure architectural consistency and code quality across the team.

Front-End Developer / Tech Lead

2023.08 - 2025.06 [1 yr 11 mos]

I developed a multi-market e-commerce application (13 markets at once), built on the SSR routing and rendering engine I designed. This increased the platform’s scalability and shortened the time needed to launch new markets. Tech stack: TypeScript 5.6, React 18, Next.js 14, App Router, Tailwind CSS, i18n, Payload CMS 2, TanStack Query 5, React Testing Library 16.

I designed and delivered a multilingual (i18n) corporate website with a Headless CMS, enabling the HR department to manage content on its own without developer support. Tech stack: TypeScript 5.2, React 18, Next.js 13, App Router, Tailwind CSS, i18n, Strapi 4 (Headless CMS).

I developed a production process management system designed to increase the efficiency and reliability of the production process. Tech stack: Node.js, REST API.

I further developed the ERP application, adding new features, optimizing key business processes and integrations with external systems. Tech stack: TypeScript 5.6, JavaScript, React 18, i18n, React Testing Library 16, TanStack Query 5, Material UI 5.

I performed technical analysis of solutions to business problems, supporting architectural decisions and technology choices.

I mentored and supported the Front-End team in architecture, best practices and coding standards, raising the quality of delivered solutions and the technological consistency of projects. I conducted regular code reviews.

Front-End Developer

2022.07 - 2023.08 [1 yr 2 mos]

I designed from scratch the engine of a multi-market e-commerce application (SSR), enabling a scalable architecture and fast rollout to new international markets. Tech stack: TypeScript 4.9, React 18, Next.js 13, App Router, Tailwind CSS, i18n, TanStack Query 4, React Testing Library 13.

I further developed the ERP application, adding new features, optimizing business processes and implementing new REST API integrations. Tech stack: JavaScript, React 18, i18n, React Testing Library 16, TanStack Query 5, Material UI 5.

I carried out a comprehensive architecture migration of the ERP application, improving code quality, typing and testability. From: JavaScript + React.js 17 + Enzyme 3. To: TypeScript 4.9 + React.js 18 + React Testing Library 13.

I increased the reliability and performance of the ERP application by refactoring components, optimizing rendering and improving test quality. These changes significantly improved system stability.

Front-End Developer / Team Leader

2022.03 - 2022.07 [5 mos]

I designed and built an internal tele-underwriting application, streamlining the risk assessment process and speeding up underwriting decisions. Tech stack: TypeScript 4.6, Angular 13, Jasmine 4, RxJS.

I stood in for my manager as Delivery Manager during a 2-month absence, ensuring continuity of project delivery and keeping schedules on track in an Agile process.

I managed a development team. I coordinated development work, conducted code reviews and ensured the quality of delivered code.

Front-End Developer / Team Leader

2021.03 - 2022.02 [1 yr]

I designed and carried out the migration of a car insurance comparison platform, improving typing quality, testability and code maintainability. From: JavaScript + React.js 16 + Enzyme 3. To: TypeScript 4.6 + React.js 17 + Testing Library 12.

I introduced Domain-Driven Design (DDD) into the development process, improving code readability and speeding up the development of new features.

I designed and delivered a serverless application (AWS Lambda) for automatic image optimization for the website, reducing asset size and improving Core Web Vitals. Tech stack: AWS S3, AWS Lambda, SAM, TypeScript 4.6.

I developed and implemented comprehensive code quality control, setting standards for the whole team. Tech stack: SonarCloud, Debricked, Raygun, ESLint, Husky, unit and E2E tests.

I integrated and launched dedicated insurance comparison tools for Radio ZET and Aion Bank, extending the reach of our services and generating additional revenue from new distribution channels.

I managed the Front-End, DevOps and infrastructure teams. I coordinated cross-department collaboration, ensuring service continuity and on-time project delivery.

I launched a pilot mentoring program combining education with hands-on practice. It gave technical high school students a start in the IT industry and let us recruit the most promising talent.

Front-End Developer

2020.03 - 2021.02 [1 yr]

I designed and delivered a document management system, eliminating manual processes and improving access to public documents. Tech stack: AWS S3, Node.js 14, TypeScript 4.2, Express.js 4.16, TypeORM 0.2.

I designed and delivered complete sales funnels in the car insurance comparison platform, increasing conversion and policy sales.

I further developed the internal Call Center system, improving agent efficiency and integrating new data sources.

I designed and delivered sales landing pages (travel and property insurance) optimized for performance and SEO, supporting lead generation. Tech stack: JavaScript, React.js 16, Enzyme 3.

I designed and implemented the company’s infrastructure monitoring system (observability), reducing incident response time. Tech stack: Grafana, Prometheus, CloudWatch, CloudTrail, Raygun, ElasticSearch.

Junior Front-End Developer

2019.03 - 2020.02 [1 yr]

I designed and delivered an application for dynamically generating contest landing pages. Tech stack: JavaScript, React 16, Enzyme 3.

I built a new car insurance comparison platform from scratch, replacing the outdated Backbone.js solution with a modern technology stack (React). Tech stack: JavaScript, React 16, Enzyme 3.

I built a new dedicated Call Center system, migrating from Backbone.js to React. Tech stack: JavaScript, React 16, Enzyme 3.

I implemented a CI/CD stack, automating the build, test and deployment process. Tech stack: Bitbucket Pipelines, SonarCloud, Debricked, AWS S3, Docker.

I built integrations with insurance companies (REST API, WebSocket), extending the platform’s offering with new partners.

I delivered a fully responsive website with a Headless CMS and SEO optimization (SSR). Tech stack: Next.js 9.5, TypeScript 3.9, Strapi 3.0.

I maintained and developed legacy applications (Backbone.js), ensuring the continuity of key systems.

IT Technician

2017.08 - 2019.02 [1 yr 7 mos]

I supported the rollout and customization of an e-commerce platform (Shoper), configuring integrations and optimizing the store’s UX.

I designed and delivered product creatives and landing pages in collaboration with global partners (NVIDIA, Intel, AMD, ASUS, MSI, GIGABYTE). Tech stack: HTML, JavaScript, CSS.

I designed and delivered email campaigns used in sales and marketing communication. Tech stack: HTML, CSS.

I designed and built a showcase PC for MSI’s booth at the Intel Extreme Masters (IEM) expo.