Tennaxia Déchets

Overview

Tennaxia Déchets is a mobile app for environment, health & safety (EHS) teams that digitises hazardous-waste tracing in the field. It plugs into Trackdéchets — the French government’s official waste-tracing registry (beta.gouv.fr) — so operators can create, sign, and follow regulatory waste slips from a phone, on-site, often without a connection.

My Role

I own the mobile platform end to end — I started it on day 0 and shipped it from an empty repo to a paid beta in under a year. That meant designing the offline-first data layer, a custom design system, and a Turborepo monorepo shared across the mobile app and web. As the team grew from 1 to 3.5 engineers, I set the architecture and conventions that let us scale without regressions.

Key Challenges

• Offline-first in the field. EHS work happens on industrial sites with poor connectivity, so the app is built around a local-first data layer that queues mutations and reconciles with the backend once a connection returns.
• Integrating a government registry. Trackdéchets has a strict regulatory contract; I drove OpenAPI spec adoption on a backend that previously had none, so the mobile client could rely on a typed, stable surface.
• Company-wide Auth0 migration. I co-led an auth migration that touched every Tennaxia product, landing it without breaking existing sessions.

Outcome

Live on the App Store and Google Play, in paid beta. The mobile platform is now the template the wider engineering org builds on — including the AI-assisted-development workflow (custom Claude Code skills and harnesses) I’m rolling out across the team.