Matthieu Bergeron

Back-End Java Developer and Scrum Master within the Customer Mobile App team responsible for developing the ADEO group application for Leroy Merlin, Bricoman, and other subsidiaries.

Consumer mobile application, over 5 million downloads on app stores, over a million members in France and several European countries (Spain, Italy, Portugal, Poland)

Core of the mission:

– Reactive programming in Java with Spring Webflux for a BFF (Back For Front).

– Implementation of functions that can call more than a dozen internal services. Data flow management to avoid long response times.

– Migration of API contracts with backward compatibility for mobile versions (versioning).

– Creation of data flow diagrams to understand network interactions.

– Functional programming, with a "Test First" approach (JUnit unit tests and Mockito integration tests).

– Production deployment, verification of application functionality in production (Datadog).

- Management of multiple environments with their own configurations.

– Refurbishment of legacy code.

Achievements:

– Development of a product feature comparison tool.

– Migration of internal API for product information.

– Addition of product geolocation (aisle and shelf).

– Activation of specific features for certain regions.

– Internal customer support and bug fixing.

Soft skills:

– Discussions with front-end developers to formalize interface contracts.

– Scrum master within a feature team: reminding priorities, task breakdown, organizing meetings and other agile rituals.

– Constant discussion with other teams to anticipate API changes upstream.

– Task estimations during sprint planning.

Python Developer at COR-e, a branch of Kpler Power, an energy consulting firm focused on aggregating energy data in Europe.

Kpler is a fast-growing data and analytics company whose mission is to facilitate sustainable and efficient trade to meet the changing needs of our world.

My achievements:

- Retrieval, formatting, and aggregation of data from various

suppliers (RTE, ENTSOE, etc.)

- Discussions with business stakeholders to better define needs

- Code migration from Python 3.7 to a more recent stack (Python 3.11, Poetry, FastAPI, Clean Architecture)

- Deployment of services

- SQL scripting to evolve database schemas

- Addition of new use cases within a Clean Architecture

- Creation of new microservices (Poetry + FastAPI + Clean Architecture)

- Deployment on servers with Podman

- Code reviews, bug fixes, participation in agile rituals

- Development of a Datadog dashboard

Senior Java Developer at Payxpert, a FinTech company offering payment services via credit card, phone, and bank transfer.

Part of the Société Générale group, Payxpert operates internationally and provides a payment platform compliant with PCI DSS security standards for online banking transactions.

With authorization from the FCA as a Payment Institution, Payxpert can receive payments in all 28 EU countries.

100% remote work environment, working within a young, dynamic, and international team of five people.

My achievements:

- Integration of the Bizum phone payment API

- Bug fixes and feature additions to the existing system (Play Framework, docker-compose, PostgreSQL, Java 8, JPA/Hibernate, ActiveMQ)

- Continuous refactoring of existing code

- Training and upskilling of development teams

- Proof of Concepts (POCs) for a new software architecture:

-> Microservices architecture with docker-compose

-> Security with Keycloak and Vault

-> "BDD" tests with Cucumber

- Development of a customer onboarding API:

-> Development in Spring Boot

-> Migration of a Legacy Java Back-End (+ Play Framework) to Kotlin (+ Spring Boot)

-> API with GraphQL

-> Test suite with JUnit, Rest-Assured

-> Scoping business needs with Event Storming sessions

- Code reviews within an Agile team, active participation in rituals (demos, retrospectives, planning, etc.)