Stéphane L.

Targeted corrective maintenance on a Python/Django backend application, involving intervention on an existing production database.

Key Contributions

- Analysis and diagnosis of backend malfunctions on an existing Django application

- Targeted correction of application errors and improvement of API stability

- Functional validation of fixes and runtime checks

- Preparation of the final deliverable and support for project closure

Results

- Backend issues identified and addressed within a defined contractual scope

- Application restored to a state compliant with the planned maintenance scope

- Structured and documented final delivery

Design and development of a backend platform for receiving, securing, and automatically distributing webhook events.

• request authentication with HMAC SHA-256;

• anti-replay protection using timestamp and nonce;

• secure validation of received data;

• asynchronous processing with Celery and Redis;

• event routing to multiple destinations;

• automatic retries with exponential backoff;

• detailed delivery and error history;

• modular architecture with FastAPI, PostgreSQL, and Alembic;

• automated tests and observability endpoints.

This personal project demonstrates the implementation of reliable backend automations for connecting multiple services via APIs and webhooks.

Design and development of Ordixa, a web application for pre-accounting intended for freelancers and small businesses. The platform centralizes, analyzes, and prepares invoices and supporting documents before transmission to the accountant.

Main achievements:

• development of a REST API with Python, FastAPI, and PostgreSQL;

• creation of the import, classification, search, and validation workflow for documents;

• implementation of automatic extraction combining document processing, classic rules, and LLM;

• pre-filling of billing information and suggestion of categories;

• detection of duplicates, anomalies, and inconsistent information;

• display of uncertainty level and human validation before any decision;

• generation of organized Excel and ZIP exports by period and category;

• secure sharing with permissions, expiration, revocation, and action tracking;

• development of the interface with React, TypeScript, and Vite.

Automation speeds up document preparation without performing accounting or making irreversible decisions on behalf of the user.