Apps and software
for sports, clubs
and education.
And when things break under the hood: backend, cloud and upgrades at a fixed price. One developer, remote, with an honest estimate of effort and cost.
About ClimbByte Studio
ClimbByte Studio is the development studio of Stephan Hölscher, a software developer from Hamburg focused on robust, scalable and precise software.
Stephan brings two worlds together:
clean code & clear structure, inspired by sports, climbing and the drive to keep getting better.
Focus areas:
- Backend & API development (Java, Spring Boot, Quarkus, Node.js)
- Legacy modernization & data migration
- Mobile & web apps (React Native, React)
- Automation & integrations (Contentful, data pipelines)
Beyond technical skills, one thing comes first:
honest advice, reliable delivery and long-term partnership.
What I build for you
Mobile Apps
Native and hybrid apps for iOS and Android: fast, modern and easy to use.
Tools: React Native, Expo, TypeScript
Web Applications
Modern web apps, user portals and dashboards: fast, scalable and intuitive.
Tools: React, Next.js, Node.js, TypeScript
Backend, APIs & Legacy Modernization
Scalable backends, stable APIs and modernization of legacy systems, from Contentful integrations to automated data pipelines.
Tools: Java, Spring Boot, Quarkus, Node.js, AWS, Contentful, Algolia, OpenSearch
Consulting & Delivery
From first idea to go-live: architecture, implementation and cloud deployment, all from one person.
Tools: Architecture, Cloud, CI/CD, DevOps
Packages and prices
Fixed packages with a clear scope. Everything else at an hourly rate of €85, or €65 for non-profit clubs and schools.
Dependency and vulnerability check
One service or app: a report with findings, priorities and a plan to fix them.
approx. 6 hours
€490
Pipeline on GitHub Actions
Build, test and deployment for one service, set up cleanly and documented.
approx. 10 hours
€890
Java or Spring Boot upgrade
One service on the current version, known vulnerabilities fixed, tests green.
from 14 hours
from €1,190
App or web prototype
One core flow as a working first version with Expo or Next.js. Larger projects in several stages.
approx. 15 hours per stage
€1,290 per stage
Website for a club or climbing gym
Up to five pages with a contact form, hosting set up.
approx. 12 hours
€790
Maintenance
Updates, dependencies and store releases for an existing app or website.
2 hours per month
€170 per month
All prices are final. As a small business under § 19 of the German VAT Act (UStG), no VAT is charged. Anything beyond the agreed scope I will quote you in advance at the hourly rate.
Projects & references
Tickmarks
Climbing logbook for iPhone: log routes, boulders and projects in seconds, offline and without an account. React Native and Expo.
View on the App Store →
TeacherDesk
Attendance app for after-school care: students check in and out with a QR pass, and the app asks for confirmation when a child may not leave alone. Plus a statistics dashboard. Built for Gymnasium Eilbektal, a secondary school in Hamburg, and in daily use there. All data stays on the device. React Native and Expo.
Climbers Delight
Climbing newsletter with a website, guides and tools. Next.js, Fastify backend and automated data pipelines.
Visit the website →Why clients work with ClimbByte
reliable, clear communication
fixed prices and a clear scope
structured, clean code
solutions, not problems
honest estimates of effort & value
personal support instead of agency anonymity
How we work together
- 1
You tell me what it is about.
- 2
We talk for 30 minutes by video, free of charge, evenings included.
- 3
You get a quote with a fixed scope and price.
- 4
I work remotely and send you progress as a test link or a short video.
- 5
Anything beyond the scope I will quote you in advance at the hourly rate.
Let's talk about your project
I reply within two business days.