Jonasz Wiącek, Developer in Wrocław, Poland
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Jonasz Wiącek

Verified Expert  in Engineering

Bio

Jonasz is a dedicated full-stack web developer with over three years of experience building performant, accessible, and scalable applications. At Nokia, he implemented an automatic tool that improved the CI/CD process while maintaining a large codebase, fixing bugs, and testing. He has created specialized plugins, adapters, and eCommerce platforms using technologies such as React, JavaScript, and Node.js. Jonasz has an eye for detail and is enthusiastic about new technology trends.

Portfolio

Freelance Clients
Admin Panels, JavaScript, TypeScript, Git, GitHub, GitHub Actions, Vite, NestJS...
Freelance Clients
JavaScript, TypeScript, Blockchain, Ethereum, Node.js, NestJS, Express.js...
RiversideFM, Inc
JavaScript, Cypress, FFmpeg, Testing, Automation, CI/CD Pipelines...

Experience

  • TypeScript - 5 years
  • React - 5 years
  • MongoDB - 5 years
  • JavaScript - 5 years
  • Node.js - 5 years
  • Java - 2 years
  • NestJS - 2 years
  • Next.js - 1 year

Availability

Part-time

Preferred Environment

Linux, Manjaro Linux, Windows, WebStorm, Slack, Ubuntu, Discord, Full-stack Development, Minimum Viable Product (MVP), Architecture

The most amazing...

...platform I've developed generates and deploys fully-working, performant websites using predefined layouts and sections in the administration panel.

Work Experience

Full-stack Developer

2021 - PRESENT
Freelance Clients
  • Developed a blockchain-based application for tracking the production and consumption of renewable energy, with data visualized on a dashboard.
  • Created a generic application core that is extendable and customizable using JSON Schemas, enabling its reuse as a customizable, paid SaaS solution.
  • Implemented end-to-end tests using Cypress to verify the most critical application functionalities.
Technologies: Admin Panels, JavaScript, TypeScript, Git, GitHub, GitHub Actions, Vite, NestJS, PostgreSQL, Auth0, Material UI, Cypress, Playwright, JSON/XML Schemas, React, Storybook

Software Engineer

2021 - PRESENT
Freelance Clients
  • Developed and deployed a standalone REST API service for efficient image and video processing, including resizing, scaling, cropping, and generating thumbnails.
  • Engineered a real-time statistics system for a call center application, improving performance and data accuracy. The system collected data on messages sent, response times, and issue resolution times and displayed this information on a dashboard.
  • Researched and organized workshops and discussion panels on topics including event sourcing, Apache Kafka, compilers, and AWS services and their use cases.
Technologies: JavaScript, TypeScript, Blockchain, Ethereum, Node.js, NestJS, Express.js, React, Next.js, MongoDB, PostgreSQL, Full-stack Development, Minimum Viable Product (MVP)

JavaScript Developer

2021 - 2022
RiversideFM, Inc
  • Scoped, implemented, and released video quality testing platform. The platform was using AWS EC2s and Docker containers to perform different testing and comparison strategies. Results were aggregated and shown on the platform UI.
  • Refactored old codebase and rewritten the project in TypeScript. Converted MVP project into a production-ready product.
  • Implemented a generic system using different strategies (scenarios) to run. That allowed the team to collect metrics, run comparisons and get the results from any video-based testing scenario.
Technologies: JavaScript, Cypress, FFmpeg, Testing, Automation, CI/CD Pipelines, Video Streaming, Full-stack Development, Minimum Viable Product (MVP)

JavaScript Developer

2019 - 2021
AdminJS
  • Maintained and implemented new features to an auto-generated administration panel.
  • Developed pluggable features installed as administrative panel extensions e.g., action log feature.
  • Implemented new connectors for an administrative panel (Firebase and Cloud Firestore) and rewrote and refactored adapters (for Mongoose and Express.js) to use TypeScript and the Jest stack.
Technologies: Admin Panels, JavaScript, Mocha, Jest, Axios, Lodash, React, Redux, Styled-components, Express.js, Firebase, Cloud Firestore, Full-stack Development, Minimum Viable Product (MVP)

JavaScript Developer

2019 - 2021
Software Brothers
  • Implemented an advanced website generator using predefined templates.
  • Maintained and built an open-source administration panel "admin-bro." Rewrote two packages in TypeScript and tested them using Jest.
  • Implemented a Firebase adapter for the administration panel and a logger feature to log actions performed in the admin panel.
  • Improved a CI/CD pipeline using a multi-stage Docker build and image caching.
  • Developed an eCommerce system for selling cars with complete order flow and third-party systems integrations (HubSpot, CRMs).
Technologies: JavaScript, TypeScript, NestJS, Express.js, Jest, MongoDB, PostgreSQL, REST, GraphQL, Kubernetes, Google Cloud Platform (GCP), Amazon Web Services (AWS), React, Vue, Full-stack Development, Minimum Viable Product (MVP)

Software Engineer

2018 - 2019
Nokia
  • Implemented an automatic tool to search through build logs history and analyze all failed builds to improve the CI/CD process.
  • Maintained a large codebase by fixing bugs and testing using JUnit and Robot.
  • Implemented a notification module (Webhooks) and sample implementation of real-time events consumption using SSE.
Technologies: Java, Spring, JavaScript, Java EE, Node.js, Robot, JUnit, Webhooks, Full-stack Development, Minimum Viable Product (MVP)

Experience

eCommerce Platform for Selling Cars

https://github.com/SoftwareBrothers/adminjs-expressjs
Implemented an eCommerce platform for selling cars. The project includes front-end parts for presenting cars, automatic order processing, invoice and order document generation, and an administration panel. The platform integrates third-party systems such as CRM, notifications, invoicing, contracting, and lead collectors.

AdminJS Firebase Adapter

https://github.com/JonaszJestem/admin-bro-firebase
Implemented a new adapter for Firestore. The adapter allows you to define a schema for your documents and inject them as entities into the administration panel. That makes all the documents in Firestore more standardized and easier to manage.

AdminJS Mongoose Adapter

https://github.com/SoftwareBrothers/adminjs-mongoose
I rewrote a TypeScript Mongoose adapter for an automatically generated administration panel. The adapter allows you to connect Mongoose models and inject them as entities in the administration panel. I also added E2E and unit tests in Jest.

AdminJS Express.js Plugin

https://github.com/SoftwareBrothers/adminjs-expressjs
An Express.js plugin that allows you to run an administration panel on Express.js-based applications. All the routings are mapped into admin panel routes. The plugin was rewritten in TypeScript. I implemented proper redirections and cookie session fixes along with proper typings of 3rd-party libraries.

Visual Quality Testing of Video Recordings

I developed and maintained an application for visual quality testing of recordings on a podcast platform utilizing Video Multi-method Assessment Fusion (VMAF) and various recording parameters. I designed the tool for reusability across different websites. Additionally, I implemented a platform that deployed real machines to test video recordings across various types of software.

Generic Renewable Energy Tracking

I implemented the front end for a generic solution to track renewable energy flow between producers and consumers. The project utilized JSON Schema to accommodate varying client requirements. The fully functional front end application employed Auth0 for authentication, React SPA for the UI, and Cypress for end-to-end testing.

Education

2016 - 2020

Bachelor's Degree in Computer Science

Wrocław University of Science and Technology - Wrocław, Poland

Skills

Libraries/APIs

Node.js, React, REST APIs, Ts-node, Mandrill API, Vue, Lodash, React Redux, FFmpeg, Playwright

Tools

Mongoose, Git, GitHub, NPM, WebStorm, Slack, GitLab, Sentry, Docker Compose, Docker Hub, JavaScript Debugging, MongoDB Atlas, Azure Kubernetes Service (AKS), Zapier, Google Kubernetes Engine (GKE), Mocha, Lerna, Firebase Authentication, Auth0

Languages

JavaScript, TypeScript, CSS, SQL, HTML, Java, HTML5, GraphQL, Less, Sass, Python, XML

Frameworks

NestJS, Express.js, Next.js, Swagger, Cypress, Material UI, Spring, Jest, Chrome, Robot, JUnit, Redux

Paradigms

Object-oriented Programming (OOP), Agile, Microservices, Unit Testing, Testing, E2E Testing, Continuous Deployment, Continuous Delivery (CD), Continuous Integration (CI), Refactoring, Test Automation, REST, Functional Programming, Automation

Platforms

Google Cloud Engine, Google App Engine, Docker, Linux, Manjaro Linux, Windows, Amazon EC2, AWS Lambda, Java EE, Kubernetes, Google Cloud Platform (GCP), Amazon Web Services (AWS), Blockchain, Ethereum, Firebase, HubSpot, Ubuntu

Storage

MongoDB, JSON, Amazon S3 (AWS S3), Google Cloud Storage, PostgreSQL, Cloud Firestore, Google Cloud, JSON/XML Schemas

Other

Software, CI/CD Pipelines, Admin Panels, Git Flow, Monorepos, Debugging, Troubleshooting, Software Troubleshooting, Email Authentication, Code Review, Source Code Review, Bug Fixes, Back-end, Front-end, APIs, Full-stack Development, Minimum Viable Product (MVP), Algorithms, Serverless, Storybook, Git Forks, Full-stack, Lambda Functions, Firebase Hosting, Firebase Cloud Functions, HubSpot CRM, HTTP, Authentication, User Authentication, API Integration, UI Components, Architecture, Machine Learning, Cryptography, Discord, Webhooks, Axios, Styled-components, JSDoc, Google Cloud Build, Amazon Machine Learning, Domain-driven Design (DDD), PWA, Video Streaming, GitHub Actions, Vite

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