01
Custom applications
Complete software built for your specific workflow. From resource planning to billing systems, we build applications that do exactly what your business needs.
Custom software · fixed price
Bespoke apps, AI automations, MVPs and internal tools. Fixed price. Live in weeks.
Custom software
01
Complete software built for your specific workflow. From resource planning to billing systems, we build applications that do exactly what your business needs.
02
Smart integrations that connect your existing tools and automate manual processes. From document classification to report generation, AI works for you.
03
From idea to live in weeks. We build minimum viable products that let you validate your concept with real users, fast.
04
Dashboards, admin tools and internal systems that replace spreadsheets and manual processes. Built for the team that uses them daily.
05
Cloud architecture, deployment and infrastructure management. From AWS/Azure/GCP migration to cost optimization and cloud operations.
06
Technical and strategic advisory for software projects. From architecture evaluation to roadmap planning and code audits.
07
Experienced developers who integrate into your team. Temporary or permanent reinforcement with professionals we know and have worked with.
How it works
We audit one workflow and prototype the fix. You get a fixed quote before anything is built.
Scope written down, price locked. Changes to scope are new quotes — never surprise invoices.
Your tool goes live in 4–8 weeks, not quarters. You see progress every week.
We keep it running, secure and up to date. Small changes included. You run the business.
Packages
Transparency is the point. Every engagement starts with a Diagnosis.
2 weeks
Process audit of one workflow, a clickable prototype and a fixed quote for the build. If you proceed, the Diagnosis is credited against the build.
4–8 weeks
One internal tool (one flow, after Diagnosis): quoting, job tracking, scheduling or reporting, deployed and in use. First 3 months of licence included. Apps, MVPs and staffing are a written fixed price, not this band.
ongoing
Hosting, security updates, regulatory and API changes, small-change hours and business-hours support.
Work

Nummo is an independent B2B product. It does not have a public website yet.

Glowapp is a cycling app for organizations.

Who's responsible
Wallion is founder-led: the person who scopes the project is the person accountable for it running. No account managers, no hand-offs, no ghost teams.
Oscar has spent 14 years building in React, Node.js, TypeScript and AWS. Recent technical direction includes TitanOS, the Linux system on Philips' 2026 TVs (18 million users in Europe), and an AI assistant at Opella / Sanofi for 11,000 employees. He works from Barcelona.
Already know what you need? Fill in this form and receive a fixed-price quote in writing within 48 business hours or a recommendation to start with a €1,900 Diagnosis.
Tell us what's breaking. We'll tell you if custom software fixes it — and exactly what it would cost.
Book a 30-minute call