# Christophe Sieradzki

> Lead Software Engineer — Currently at Positive (Sarbacane) · Lille, France

Distributed architecture, devops, and AI: I design reliable platforms from architecture to deployment, and help teams ship with confidence.

- **Website**: https://christophe-sieradzki.fr/en/
- **Email**: [contact@christophe-sieradzki.fr](mailto:contact@christophe-sieradzki.fr)
- **LinkedIn**: https://fr.linkedin.com/in/christophe-sieradzki

[Lire ce site en français](https://christophe-sieradzki.fr/index.md)

## Experience

### Lead Software Engineer — Positive

*April 2025 – present · Experience*

Promoted to lead after five years at Sarbacane, I lead the Positive group’s email and SMS delivery platform, from build to day-to-day operations, with my team of engineers. I migrated our deployments from Apache Mesos to the HashiCorp stack (Nomad, Vault, Consul), brought LLMs into the moderation of outgoing campaigns (spam and fraud detection) with LangChain, and am leading the team’s adoption of coding agents (harness engineering, CI/CD automation).

**Skills**: HashiCorp Nomad, HashiCorp Vault, HashiCorp Consul, Java, Quarkus, LLM integration, LangChain, Decision models, Claude Code, RabbitMQ, Redis, MongoDB, Elastic Stack, Docker, GitLab CI, Jenkins, Team leadership

### Java Software Engineer — Sarbacane (Positive)

*January 2021 – April 2025 · Experience*

I built and ran the new contact management platform and designed the contact-list API with an API-first approach (OpenAPI). I also set up an event-sourcing architecture with CQRS, developed an asynchronous task orchestrator that works across Java and Go, redesigned the shopping cart, connected it to the internal CRM, and brought the QA team into our deployment process.

**Skills**: Java, Quarkus, Go, Event sourcing & CQRS, OpenAPI, PostgreSQL, MongoDB, Redis, RabbitMQ, Elastic Stack, Python, Apache Mesos, GitLab CI, Jenkins

### Junior Software Engineer — Sarbacane (Positive)

*January 2020 – January 2021 · Experience*

My first experience with microservices architecture, I maintained and extended the Sarbacane Sunrise SaaS platform (microservices architecture), improved the local development experience, and shipped key features for personalizing marketing content.

**Skills**: Go, gRPC, Spring, Angular, Symfony, MongoDB

### Back-end Developer — Adictiz

*July 2019 – January 2020 · Experience · Internship*

For my final-year internship, I joined the team behind the Adictiz Box, a SaaS platform that lets brands create gamified marketing campaigns. I built two new game mechanics, added OAuth authentication, documented the API with OpenAPI, and optimized the GitLab CI pipelines.

**Skills**: PHP, Symfony, MySQL, MongoDB, Docker, OpenAPI, OAuth, GitLab CI

### Master’s degree in Computer Science — Université du Québec à Chicoutimi

*2018 – 2019 · Education*

A one-year exchange between EIL Côte d’Opale and UQAC in Quebec: a master’s degree in computer science, earned on top of my French engineering degree.

### PHP Web Developer — Atecna

*June – August 2018 · Experience · Internship*

On the maintenance team for client websites, I learned Symfony, handled client requests, and built a Vue.js tool to track them end to end. It was this internship that steered me toward back-end work.

**Skills**: PHP, Symfony, Vue.js

### Web Developer — Babylon Radio

*June – August 2017 · Experience · Internship*

In Dublin, I helped build Babylon Radio’s new website. It was my first web development role, working full stack: Node.js and MongoDB on the back end, Pug and Less on the front end, on the KeystoneJS CMS.

**Skills**: Node.js, MongoDB, Pug, Less, KeystoneJS

### Engineering degree in Computer Science — EIL Côte d’Opale

*2014 – 2019 · Education*

Integrated preparatory classes, then the engineering program, majoring in computer science. French engineering degree (master’s level), awarded in 2019. Student organization president of Ch'ti Gamers 2017 - 2018

## Skills

### Languages & frameworks

- Java, Quarkus, Spring, Go
- **Also**: Python, PHP / Symfony, Node.js, Angular

### Technical leadership

- Team leadership, Project delivery, Scrum, Developer experience (DX)

### Architecture

- Microservices, Event sourcing & CQRS, API-first (OpenAPI), gRPC, RabbitMQ

### Platform & delivery

- HashiCorp Nomad · Vault · Consul, Docker, CI/CD (GitLab CI, Jenkins)
- **Also**: Kubernetes, Apache Mesos

### Applied AI

- LLM integration, Decision models, LangChain, Claude Code

### Data & observability

- PostgreSQL, MongoDB, Redis, Elastic Stack
- **Also**: MySQL

## Contact

Have a question, an opportunity, or just want to chat? Drop me a line.

- **Email**: [contact@christophe-sieradzki.fr](mailto:contact@christophe-sieradzki.fr)
- **LinkedIn**: https://fr.linkedin.com/in/christophe-sieradzki