Matthijs Lanser • Freelance Software Engineer
Building tech & products that scale
From early-stage startups to enterprises, I turn complex technical challenges into elegant solutions.
Work
Wealthbase
Personal finance app that helps you understand your financial life across accounts, currencies, assets, spending, income, investments, and cash flow, with privacy built in.
Finlay
Built tech & product at Finlay. Built an AI recruitment platform from scratch, hiring and managing a team of five cross-functional engineers. Delivered ATS capabilities, multi-agent AI workflows, Slack and LinkedIn integrations, and SaaS infrastructure. Focused on technical strategy and architecture.
Citya
Demand-responsive transport systems deployed across Czech Republic. Focused on architecture modernization, and delivering innovative features for passengers and drivers.
Mews
Built payment processing solutions from the ground up, that currently process €800M+ monthly for 12,500+ hotels in 85 countries. Integrated multiple payment gateways, tokenization services, payments terminals, and worked on PCI DSS compliance.
Iguana Technology
Business application and public-facing marketplace for the luxury yachting rental market. Supported development on existing business application, and build a public-facing booking platform from scatch. Involved in technical leadership, mentoring, and architecture.
Wylance
Full-stack developer building web applications. Worked on ERP systems for sports event planning and management, and a support ticketing system with in-browser Active Directory management for Windows networks.
OkayR
OKR management tool for teams to align goals and track progress. Heavily focused on automation and integrations.
About
I'm Matthijs, a freelance software engineer with a passion for turning your ideas into real products and helping businesses grow.
Based in Prague, Czech Republic. I've spent years working with companies ranging from early-stage startups to enterprises. From building complex payment systems to leading engineering teams shipping AI-powered products, I thrive on complex challenges.
Backend & Architecture
C#, .NET Core, Node.js, PostgreSQL, SQL, EF Core, CQRS, Distributed systems, GCP, Azure
Frontend & Product
React, TypeScript, Next.js, SCSS, Design Systems, Figma, User Experience
Leadership & AI
Team Leading, Hiring, Mentoring, Technical Strategy, Kanban, LLMs, Agentic systems
How I can help
Whether you're validating an idea or scaling to millions of users, I can bring both technical depth and strategic thinking.
Product Development
Full-cycle development from concept to launch. I work closely with founders to transform ideas into production-ready products, handling everything from architecture to deployment.
- MVP to Scale
- Full-Stack
- CI/CD
Technical Architecture
Designing systems that scale. Whether you're hitting growth bottlenecks or planning for the future, I help architect solutions that balance immediate needs with long-term flexibility.
- System Design
- Scalability
- Performance
Team Augmentation
Embedded engineering support for complex initiatives. I integrate with your team to accelerate delivery, mentor developers, and establish best practices.
- Mentorship
- Code Reviews
- Best Practices
Technical Leadership
Fractional CTO services for startups. whether it's defining technical strategy, or building and leading engineering teams, I help founders navigate the technical journey.
- Strategy
- Hiring
- Leadership
Let's build something
Have a project in mind? I'm always interested in hearing about new opportunities. Let's discuss how I can help bring your products to life.