Bjorn Krols
Software engineer
Introduction
I am an experienced software engineer with a passion for delivering high-quality, scalable and secure solutions.
I am open to working with clients from various industries on both short-term and long-term projects.
Technologies and Tools
These are some of the technologies and tools I have worked with in the past. I am always open to learning new technologies and frameworks.
- Languages
- JavaScript, TypeScript, Python, Go, Java, Lua, Bash
- Frontend
- React, React Native, Expo, Next.js, Vue, Nuxt, Electron, Apollo, Tailwind, HTML5, CSS, Vite, TanStack Router, TanStack Query, Storybook
- Backend
- Node.js, Express, Koa, tRPC, NestJS, TypeGraphQL, TypeORM, Prisma, Apollo Server, GraphQL, REST, Hono, Pothos, Drizzle
- Databases
- PostgreSQL, MySQL, Oracle, SQLite, DynamoDB, Redis, BigQuery, DuckDB
- Infrastructure
- AWS, Google Cloud Platform, Serverless, Terraform, Docker, Firebase, Fly, Render, PlanetScale
- Data Science
- Jupyter, Pandas, NumPy, Plotly, PyTorch, Polars, scikit-learn, ONNX Runtime
- Testing
- Jest, Cypress, Vitest, Playwright, Testing Library
- CI/CD
- GitHub Actions, GitLab CI, Jenkins, CircleCI
Work Experience
- Skipr2025 → now
- Rush2023 → now
- Lab Box2023 → 2023
- Shippr2019 → 2023
- The Studio2018 → 2019
- BICS2016 → 2018
- OSBot2014 → 2016
Senior Software Engineer at Skipr
February 2025 - Now
Skipr is an all-in-one solution for managing corporate mobility.
- TypeScript
- Go
- React
- Next.js
- Capacitor
- PostgreSQL
- Docker
- Kubernetes
- Google Cloud Platform
- GitHub Actions
- Highlight: I integrated Strong Customer Authentication, built the company's first agentic features from scratch, and consolidated the codebase into a monorepo.
Senior Software Engineer at Rush
December 2023 - Now
Rush is a full-stack software studio.
- TypeScript
- Python
- Next.js
- React
- React Native
- Expo
- Tailwind
- tRPC
- NestJS
- Pandas
- GitHub Actions
- Highlight: I managed several projects end to end, encompassing infrastructure, backend, frontend, mobile development, and data science.
Senior Software Engineer at Lab Box
March 2023 - December 2023 · 10 Months
Lab Box is a start-up studio focusing on the future of mobility, backed by D’Ieteren.
- TypeScript
- Python
- Next.js
- React
- React Native
- Expo
- Tailwind
- tRPC
- NestJS
- Apollo
- GraphQL
- Pandas
- GitHub Actions
- Highlight: I've led a handful of projects end to end, launched multiple React Native apps on app stores from scratch, and implemented various data and business intelligence pipelines using Python and a range of data science tools.
- Exit reason: The lab and its projects were merged into D’Ieteren.
Senior Software Engineer at Shippr
August 2019 - March 2023 · 3 years 8 months
Shippr (https://shippr.io) is a logistics marketplace connecting companies and drivers.
- TypeScript
- React
- React Native
- Expo
- Tailwind
- Express
- Apollo
- GraphQL
- PostgreSQL
- Redis
- AWS
- Terraform
- Docker
- Jest
- Cypress
- GitLab CI
- Highlight: I set up the e-payment infrastructure for the company from scratch, allowing automatic payments from customers and payouts to drivers.
- Exit reason: I was looking for a new challenge as I transitioned into freelancing.
Software Engineer at The Studio
February 2018 - June 2019 · 1 year 5 months
A Belfius (Belgian bank) innovation lab.
- JavaScript
- Vue
- AngularJS
- Tailwind
- Express
- PostgreSQL
- DynamoDB
- AWS
- Serverless
- Cypress
- CircleCI
- Highlight: Led a small team to build a group payment and fundraising platform from scratch.
- Exit reason: The lab was closed after multiple products failed to reach product-market fit.
Software Engineer at BICS
June 2016 - January 2018 · 1 year 8 months
A Proximus (Belgian telecom company) subsidiary.
- Java
- JavaScript
- JSF
- React
- Bootstrap
- Spring
- Oracle
- Red Hat
- JUnit
- Jenkins
- Highlight: Spearheaded the migration of legacy JSF interfaces to a more modern React-based architecture.
- Exit reason: Desire to work with a more modern stack.
Script Developer at OSBot
January 2014 - June 2016 · 2 years 6 months
OSBot provides RuneScape automation software.
- Java
- Swing
- MySQL
- Highlight: Tutored multiple new developers in Java and Swing.
- Exit reason: Desire to work in a team, instead of working alone.
Personal Projects
In addition to client work, I enjoy exploring new technologies and working on personal projects. Here are a few examples of side projects that I have worked on:
Formspark
2018 - Present
Simple & powerful form solution for developers
- TypeScript
- React
- Next.js
- Vite
- Apollo
- GraphQL
- Pothos
- Tailwind
- Hono
- Drizzle
- PostgreSQL
- AWS
- Terraform
- Vitest
- Storybook
- GitHub Actions
Botpoison
2021 - Present
Keeps bots out of forms and spam out of inboxes, with an invisible CAPTCHA alternative and a spam classifier.
- TypeScript
- React
- Next.js
- Apollo
- GraphQL
- Pothos
- Tailwind
- Hono
- Drizzle
- PostgreSQL
- Python
- scikit-learn
- Polars
- ONNX Runtime
- AWS
- Terraform
- Vitest
- Storybook
- GitHub Actions
Postcraft
2022 - Present
The email builder for product teams: design transactional email visually or in code, then render it through one API.
- TypeScript
- React
- TanStack Router
- TanStack Query
- Tailwind
- Vite
- Hono
- Drizzle
- PostgreSQL
- Handlebars
- AWS SES
- Docker
- Vitest
- Playwright
- GitHub Actions
Education
2011: High School Diploma - Collège Saint-Guibert, Gembloux, Belgium
Languages
- French: Native proficiency
- Dutch: Native proficiency
- English: Full professional proficiency
- Spanish: Elementary proficiency
- Portuguese: Elementary proficiency
- German: Elementary proficiency