Legacy ERP → Modern

Full-stack modernization for Gabriel Informatik • 2025–2026

T&M • 80–160 h/month • PostgreSQL + Node.js + React

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The Challenge

Gabriel Informatik's client had a critical business ERP that managed all operations. The legacy application was based on outdated code that could no longer be compiled. It used stored procedures in a non-optimized way to generate reports from the existing database and could not accommodate new requirements (including accessibility on tablets/mobiles for drivers and parents in their operations).

A quick prototype had been built to validate the direction. The client needed the real, production-grade solution.

Solution Architecture

PostgreSQL 17
Node.js (Backend / API)
React (Frontend)
JSON-native data
Mobile / Tablet ready

Database: PostgreSQL 17 (current schema adapted, stored procedures only when truly needed). Excellent JSON support for future flexibility. No license costs. Secure handling of sensitive business information.

Backend: Node.js web services acting as the bridge between frontend and database.

Frontend: React static application, deployable via the same Node instance or separately. Designed for accessibility on tablets and mobiles.

Delivery Approach (Agile, Predictable)

Prototype validation → agreed architecture and stack.
Version 1.0 — Replicate all existing functionality from the legacy system (including reporting features) plus any modifications that do not affect delivery timelines.
Version 2.0 — All new features not covered in v1.0.
Ongoing — Meetings, documentation (developer + installation manuals), and continuous support.

At least one deliverable every 15 days (minimum ~20 hours/week). Invoices reflect exact hours spent. Frame agreement up to 2 years with option to extend.

Investment Model

Time & Materials — 80 to 160 hours per month typical.

Monthly range: CHF 12,000 – 24,000 (at 150 CHF/hour). TVA 8.1% not included.

Current rates are 150 CHF/hour. Flexible to client pace while guaranteeing steady progress.

Status (mid-2026)

Prototype phase completed. Active development of v1.0 / continuing into v2.0 features. Regular invoicing and timesheets (example: 38 hours in one month for development + meetings + deployment).

Why It Matters

This project demonstrates the A-Team's strength in legacy rescue: taking unmaintainable, business-critical systems and giving them a modern, future-proof foundation without losing a single existing capability — while adding the flexibility the client actually needs.

Have a legacy system that "can't be touched"? Let's talk →