EN/NL

Lars Kerff Full stack developer

Freelance full stack developer based in Roermond, Netherlands. TypeScript (React/Vue/NestJs) and PHP (Laravel/Symfony) across web apps, APIs and CMS platforms, with a track record of leading development squads and modernizing legacy systems.

Leff Design

Kapellerlaan 44,6041 JD RoermondThe Netherlands
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– PresentRoermond

Leff Design / Fullstack Developer (Owner)

Freelance full stack work across several client projects, based in Roermond.

Projects

Own projects

  • qaikprompt.com: A visual AI prompt builder, a tool to build AI prompt flows, including admin and user dashboard (NestJs, React, TypeScript) (soon online)
  • qaikpost.com: AI post generator API for content management systems like WordPress, Shopify etc., including a PHP plugin (NestJs, React, TypeScript)
    (soon online)
  • Laravel Resources to TypeScript Types: Composer package that converts Laravel Resources to TypeScript types

Client projects

Technical: NestJs, React, TypeScript, Laravel, Vue, Google Cloud, Kubernetes

– Nuenen

Veldsink & VCN / Lead Developer (Freelance)

https://www.vcn.nl

Led a development squad within a large-scale insurance software project, working with Docker-based environments, CI/CD pipelines and tools like Git, Bitbucket, JIRA and Confluence. Designed and implemented microservice REST APIs (Symfony) and built and maintained REST APIs and a TypeScript/React frontend admin dashboard.

Projects

  • Insurance Process Automation: Developed and maintained proprietary software automating the complete insurance process within internal systems.
  • Microservices Refactor: Refactored a large monolith into 20+ microservices while ensuring stability of the legacy application (Symfony).
  • Admin Dashboard: Built and maintained a TypeScript/React frontend admin dashboard.

Technical: PHP, SQL, Symfony, ReactJs, TypeScript, Docker, Redis, ElasticSearch, Kafka

– Roermond

Udw / Lead Developer (Freelance)

https://udw.nl

Lead developer on car lease configurator plugins and dealer API integrations.

Projects

Technical: PHP, SQL, SOAP, JavaScript, WordPress, WordPress plugin development

– Amsterdam

WPG Uitgevers / Full Stack Developer (Freelance)

Developed & maintained 20+ websites, webshops, APIs and plugins, and implemented APIs and custom WordPress plugins for WPG Uitgevers.

Projects

  • kinderboeken.nl: Website maintained and extended (Laravel, ReactJs, WordPress).
  • coachfinder.nl: Website maintained and extended (Laravel, ReactJs, WordPress).
  • happinez.nl: Website maintained and extended (Laravel, ReactJs, WordPress).
  • vn.nl: Website maintained and extended (Laravel, ReactJs, WordPress).

Technical: PHP, SQL, Laravel, JavaScript, ReactJs, ElasticSearch, WordPress, KeyCloak

– Amsterdam

Follow (besthoteloffers B.V.) / Lead Developer (Freelance)

https://follow.global

Led development & architecture of a REST API platform for travel integrations, built the ReactJs frontend, and managed project delivery and development processes.

Projects

  • follow.global: REST API travel integration platform integrating booking.com, Tiqets, Kiwi (flights), OpenTable, and other APIs.

Technical: PHP, SQL, Laravel, JavaScript, ReactJs, travel API integrations, PSP integration (Adyen), DevOps

– Amsterdam

Sterrk / Developer (Contract placement)

Developer placements across multiple client projects via Sterrk.

Projects

  • Growing Minds / Formsuite 2.0: Led architecture redesign & implementation, introduced Scrum workflow.
  • MyParcel / SendMyParcel.be: Refactored Angular app, integrated bPost API, revamped white-label platform.
  • MyParcel / DeliverDutch.nl: Developed white-label shipping app for PostNL consumers.
  • itvacatures.amsterdam: Maintained and extended Laravel/Vue platform.

Technical: Symfony, Laravel, JavaScript, TypeScript, Angular, PostgreSQL, Redis, AWS, SOAP, Salesforce API

– Utrecht

CLWeb / Developer (Freelance)

https://clweb.nl

Full stack development across affiliate platforms, feed optimization tools, and lead-developer engagements.

Projects

  • LegalCross.nl (Omnius): Lead developer, integrated APIs (Mollie, Mailgun, WhatsApp), PDF exports.
  • Feeding Monitor: Built a data-driven application for feed optimization and analysis.
  • Bewinkel.nl: High-performance affiliate platform (ElasticSearch, Docker, Jenkins).
  • mychiptuningfiles.com: Webshop for chiptuning files.

Technical: Laravel, PHP, MySQL, JavaScript, ElasticSearch, Docker, Jenkins, Google APIs, Facebook API

– Heerlen

Leff Design / Startup

Started as an independent contractor in 2011, developed a large number of websites and web applications in several frameworks (Laravel / VueJS / ReactJs) and multiple CMSs such as Magento, WordPress and Drupal. In charge of the entire process from start to finish: project management, technical design, requirement engineering, backend and frontend. Also gained experience in server management and coaching of interns.