Robert-Jan Mahieu
Verified Expert in Engineering
Back-end Developer
Robert-Jan is a back-end developer with 13 years of experience. He recently helped scale a Dutch fintech startup from the first lines of code to unicorn status. Robert-Jan is exceptionally skilled at quickly finding his way in new platforms or APIs and database design and performance optimization. He takes ownership, delivers on time, and aims for the best possible outcome in any given scenario.
Portfolio
Experience
Availability
Preferred Environment
MacOS, PhpStorm, PHP, MySQL, Vue, JavaScript, Apache2, Git, Amazon Web Services (AWS)
The most amazing...
...thing I've done is to help a fintech startup scale from the very first lines of code to unicorn status.
Work Experience
Founder | Software Engineer
Circalex
- Founded my own company as a solo entrepreneur offering SaaS solutions.
- Built a flexible and custom back-end framework in PHP to use as a starting point for any SaaS.
- Launched multiple products in quick succession, AppMon.dev, Circalex.com, and LegalTechWork.com.
Principal Back-end Developer
bunq
- Built the core backing architecture for the back end from the first lines of code and scaled it from zero to a payment volume of €40 billion a year.
- Migrated the entire back-end API and database from private servers to AWS cloud infrastructure with less than one-hour downtime.
- Designed, implemented, and coordinated multiple payment systems in record time, with market-leading partners such as Mastercard, EBA Clearing, Wise, and Checkout.com.
- Implemented and designed onboarding flows with advanced KYC.
- Analyzed usage data to help detect phishing, fraud, or money laundering and implemented measures to combat this.
- Invented a communication protocol for which a US patent was granted.
Software Developer
BinckBank
- Implemented new features and bug fixes in a B2B trading platform.
- Wrote tools to help developers throughout the company perform their work more effectively and save time.
- Achieved certification after extensive training in stock markets and associated theory relevant to the retail brokerage business of the company.
Junior Software Developer
Alex Vermogensbank
- Resolved many memory leaks in the Delphi code of the back-end of a service-oriented architecture (SOA).
- Was promoted from junior to medior in just six months.
- Refactored the code for the yearly trading reports for end-users from the old deprecated platform to the newly introduced codebase and coding standards.
Experience
AppMon.dev - Application Monitoring Software
I designed and built every aspect, from front-end design, with a back-end API to server maintenance. The project took two weeks from the initial idea to public launch.
Circalex
The entire project (back end and front end, including UI/UX design) was developed by me in less than two months from the first idea to the public launch.
OpWieStemmen.nl
Skills
Languages
PHP, PHP 7, XML, SQL, JavaScript, HTML, Java, CSS, Delphi, C++, Python
Frameworks
Twig, Tailwind CSS, Laravel, CodeIgniter, Bootstrap, Symfony
Libraries/APIs
REST APIs, Vue, Stripe, Stripe API, Twilio API, Node.js
Tools
PhpStorm, Git, Apple Push Notifications, GitLab, Amazon Athena, Apache, GitLab CI/CD, NPM, Sentry
Paradigms
REST, Clean Code, Back-end Architecture, Service-oriented Architecture (SOA), Test-driven Development (TDD)
Platforms
MacOS, Apache2, Oracle, Amazon Web Services (AWS), Ubuntu, Twilio, Docker
Storage
MySQL, Amazon Aurora, Databases, JSON, RDBMS, PL/SQL, Redis, Elasticsearch, MariaDB
Other
Computer Science, APIs, Payment APIs, Card Payments, Online Banking, Mobile Payments, Performance Tuning, Back-end, Mobile Banking, Payment Processing, Payment Security, Payment Networks, Fintech, SOAP, API Integration, Software as a Service (SaaS), Back-end Development, Back-end Performance, Mobile Back-end, SEO Audits, Full-stack, Scripting Languages, Message Queues, Architecture, Search, Documentation, PDF, Front-end, Code Review, IT Deployments, Build Releases, Release Management, Mastercard, Credit Cards
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