Project · ERP de Arclo Systems
Project 03 / 07: ERP de Arclo Systems
2026 · Arclo Systems · Architecture and development
Arclo Systems · 2026
CRM, projects and double-entry accounting in one system, with 2FA, audit logs and an MCP server.
The problem
Arclo kept its CRM, projects and accounting in three tools that didn't talk to each other. It is an internal system, behind login and 2FA.
What I did
01 / 04
I built its 11 CRM, project and finance modules.
A NestJS REST API with Prisma and PostgreSQL, and a React 19 PWA.
02 / 04
I modeled double-entry accounting in colones and dollars.
Signing in requires 2FA, permissions are checked on every request and a hash-chained audit log prevents editing or deleting records.
03 / 04
I added an MCP server with OAuth 2.1.
That exposes Arclo's engineering standards to AI agents.
04 / 04
I versioned the schema in 16 migrations with tested rollback.
And wrote 213 unit, integration and E2E test files with Vitest, Testcontainers and Playwright.
Results
- Every client moves from lead to quote, contract and biweekly deliveries in one system, and follows their progress from their own portal.
- Each project's profitability comes out of the same books.
Stack
- React
- NestJS
- PostgreSQL
- Prisma
- MCP
- Vitest
- Playwright