Arnaud Grousset · Eleyone

Chiliz is the blockchain company behind Socios.com and its fan tokens — crypto tokens tied to sports clubs — and runs its own chain. I designed and implemented on-chain financial flows for that ecosystem, within a domain-driven microservices architecture — mainly the wallet service, plus the NFT and user services — across three squads of eight people. Part of the work was redrawing boundaries: service decompositions to narrow the wallet’s scope, migrating Chiliz-issued tokens from an Ethereum fork to Chiliz Chain, moving wallets from custodial to non-custodial with the DFNS provider. From May 2024, with the team, I rebuilt in Symfony the finance team’s internal application, started in Python in January 2024 and then abandoned: first the on-chain operations that traders and market makers run themselves across several DEXs (decentralised exchanges) — deposits, withdrawals, swaps —, then the decision-support tools, including the NCS/CS calculation over about 90 pools, which the application took over and proved against the BI (business intelligence) export until it became the reference. I also designed a batch processing of on-chain operations, by chaining, which reached the test environment but was never put into production. Alongside, an internal Node.js and TypeScript indexer collected transactions for verification and reconciliation, and early multi-chain work opened the application to Solana.

At a CRM integrator, I designed custom solutions around SugarCRM for several clients. For Qérys, a French retailer, I built complete plugins that turned SugarCRM into a retail quoting tool — a use case it was never designed for. I was the team’s technical referent: solution design, code reviews, developer support.

On the high-volume e-commerce platform of Mister Auto, a subsidiary of the PSA automotive group, I owned the technical solution choices and wrote the platform’s technical specifications. I led a team of six developers, on delivery priorities and code quality. This was the assignment where I held the team lead role, coordinating the team’s work day to day. The assignment was carried out through Modis, an IT consultancy.

April Technologies is the IT arm of April, a French insurance group. This was my second time on its insurance management application, which I had worked on in 2013–2014 as a contractor at CGI. The frontend, in Symfony 1.3 and jQuery, talked over SOAP to a Java and Hibernate backend; my planned scope was that frontend and new feature development. I went and read the Java to debug precisely and report exact causes to the backend developers, then took features end to end — Java entity, database, business validations, screen. The assignment was carried out through Modis, an IT consultancy.

Orange is France’s main telecom operator. On its CRV application — the visit reports of field sales reps selling telecom equipment to businesses —, a legacy Zend Framework 1 application, read-only on an Oracle database managed elsewhere in the IT system, I refactored 90% of the code for performance and maintainability, with no production downtime. I measured where the time went before touching the code, and settled on a reversible trade-off: pages that took seconds came down to milliseconds. With no tech lead on the team, I was the one making the technical decisions. I also designed and built a new Zend Framework 2 application with a BackboneJS and Marionette frontend. The assignment was carried out through Modis, an IT consultancy.

At Avenue Web Système, in Grenoble, I designed and built applications for local government bodies in PHP and Zend Framework 1, and took over existing Java applets — that is where I did Java for cryptography PHP could not handle at the time. Then, as a consultant at FHM Solutions, I moved from assignment to assignment: merging two websites in CakePHP at Primavista; new features for the information systems merger of 1001 Listes – Galeries Lafayette, a wedding-registry brand of the Galeries Lafayette department stores, in Zend Framework 1; refactoring to Zend best practices at BETC, an advertising agency, my first experience leading junior developers; development and project management on the April insurance group’s application, in Symfony 1.3 and Java, as a contractor at CGI; and reinforcing the production team on Drupal and WordPress at Visual Link.

Ton Pote le Geek (“your geek friend”) is my own freelance business. I build automated systems and custom tools for entrepreneurs and small businesses: connecting the tools they already use — CRM, email, payments, appointment scheduling — to remove hours of manual work every week, and applications for their own clients. For those who want to own their automation system rather than rent it, I deploy self-hosted n8n infrastructure. The most complete engagement is a profitability calculator for a training business: it started as an iframe with no database and became a full application once usage showed that users came back — about 400 accounts created, 300 active —, and I am now turning it into a product sold under my own name. Same standards as my enterprise engagements: versioned, tested, documented, built to run without me.