At Semji, we’re deeply transforming how major brands create and optimize their content with our all-in-one Content Marketing platform. Our solution empowers companies to manage every step of their content strategy—from identifying visibility opportunities to precisely measuring performance and ROI.
On a daily basis, our technical challenges are numerous, often exciting, and sometimes highly ambitious:
We aggregate large volumes of data in real time (web crawling, content extraction, data retrieval and storage from numerous third-party APIs).
We develop truly innovative features powered by cutting-edge generative AI models from OpenAI and Anthropic.
We consider UI/UX a real differentiator, with high-performance stakes.
Our infrastructure is hosted on AWS, and we’re constantly working to industrialize it, optimize performance, and control costs (DevOps mindset).
We’re data lovers—charts, metrics, and monitoring are our thing. Our stack is monitored at multiple levels with tools like Kibana, New Relic, and Metabase.
More broadly, we tackle all the classic challenges of building and scaling a full SaaS application.
Today, over 400 companies in 15 countries rely on Semji every day, including iconic brands like Leroy Merlin, La Vie Claire, Macif, and Qonto.
👉 Feel free to create a free trial at https://app.semji.com and see it in action!
You’ll join a passionate and ambitious R&D team with a strong technical level—eager to welcome you and build great things together.
The team currently includes 12 people:
David, Arnaud, Mouhamed, Manuel, Gaëlle, Abdel – Developers
Ayyoub – Front-End Tech Lead
Sébastien – Back-End Tech Lead
Julien & François – Product Managers
Zineb & Valentin – Product Designers
Michael – AI Manager
Olivier – CTO
You’ll be involved in the full development lifecycle of our platform, from brainstorming and design through to production deployment and monitoring.
Your core responsibilities will include:
Designing and developing Semji’s core application, especially the backend: main REST API in PHP (Symfony + API Platform stack), asynchronous workers using Messenger and AWS SQS, internal APIs in PHP, Node.js or Python, and our well-structured Postgres database.
Prototyping innovative features.
Sharing knowledge and supporting the team (brainstorms, code reviews, pair programming…).
Contributing to our quality-first approach: code reviews, improving the test stack, and keeping architecture, codebase, and libraries up to date.
Maintaining and modernizing our DevOps practices and tooling (CI/CD, Kubernetes cluster, monitoring…).
Actively improving all aspects of our current tech stack: https://stackshare.io/semji/semji (PHP 8+/Symfony 7+, Postgres 16+, Docker, AWS Cloud, JS/React, GitHub, GitHub Actions…).
Once per quarter, you’ll take part in our “Innov R&D Weeks”, where you’ll lead a technical or functional innovation project of your choice—outside of the product roadmap constraints.
You have 4+ years of experience as a Back-End Developer, ideally within a SaaS environment.
You’re passionate and versatile, able to tackle many problems quickly and efficiently.
You’re autonomous, keep up with the latest tech, and care about best practices in development.
You’re pragmatic and can propose technical solutions aligned with business needs.
You want end-to-end ownership of the product: you’re as curious about functional product challenges as you are about infrastructure and Ops.
Most importantly, you thrive in team environments!
We’re looking for an experienced profile ready to bring their knowledge to our SaaS platform and team—with a long-term mindset.
Must-Have Technical Skills
Strong proficiency in PHP 8+, Symfony 7+, and the surrounding ecosystem
Solid SQL skills and experience designing and scaling PostgreSQL databases
Excellent understanding of web application architecture
Proficient with Git
Nice-to-Haves
Experience with API Platform
Familiarity with DevOps (Docker, Linux, AWS, New Relic…)
Knowledge of JavaScript and its ecosystem
A passion for LEGO
And a high score at Curvytron 😉
Location: Lyon 9 (Metro D – Gare de Vaise)
High-end gear of your choice (Mac or Linux), renewed every 3 years
Access to top-tier tools (GitHub, Copilot, ChatGPT Plus, Slack, IDE of your choice…)
Agile methodology: Scrum & Kanban
Hybrid setup: 2 days remote/week after onboarding
Salary range: €42K–€55K gross/year
One extra week of paid vacation to support work-life balance
Sustainable mobility allowance: €500/year via Swile
Lunch vouchers: €8 (50/50 split)
Great health insurance via Génération (50/50 coverage)
Top-notch coffee + beer tap
Interview Process
Initial phone screening with Julia
First round with Olivier Balais (CTO°
Technical assessment with Olivier Balais (CTO) and our Tech Lead Back-End
Final round with the co-founders
These companies are also recruiting for the position of “Développement de logiciels et de sites Web”.
Lyon · Versailles · Toulouse