Senior Back-end Engineer Node.Js - Wizz

Wizz App; Paris; Hybride; EUR 90 000 - 130 000; Plein temps

Avantages offerts par ce poste

Lunch voucher

Gymlib

SideCare health

Wellness Paris

Unlimited vacation

Remote days

Résumé du poste

Voodoo, the creator of Wizz, is seeking a Senior Backend Engineer in Paris to shape the backend architecture for a high-growth social app. You will own scalability, reliability, and decision-making, partnering with product and engineering to drive the platform forward.

You will work across Node.js and Go, in a cloud-first stack, with APIs, data stores, and distributed systems at scale. Join a high-performing team dedicated to safe, engaging user experiences.

Qualifications

• 5+ years of backend development experience in a consumer app context.
• Must be fluent in French and able to work in a Paris-based team.
• Experience building scalable APIs and backend services.
• Strong knowledge of high-traffic distributed systems and architecture.
• Familiarity with Node.js, Go, and cloud services (GCP/AWS).
• DevOps experience with automation and CI/CD is a plus.

Responsabilités

• Own the backend architecture ensuring scalability, performance, and reliability for millions of users.
• Collaborate with product to influence decisions with a strong technical perspective.
• Design, implement, deploy, and maintain scalable backend systems with safety and moderation features.
• Integrate third-party services (analytics, moderation, cloud tools) for secure UX.
• Define and promote best practices in reliability, observability, and infra management.
• Contribute to backend infrastructure evolution to support rapid iterations and safe growth.
• Improve system performance and scalability of high-traffic distributed systems.

Connaissances

5+ years backend

Fluent French

Node.js

GCP/AWS

APIs

Distributed systems

DevOps

Outils

Go

Firebase

MongoDB

Redis

Cloud Run

Pub/Sub

S3

CloudFront

BigQuery

GitHub Actions

Docker

gcloud CLI

AWS CLI

Description du poste

About Voodoo

Founded in 2013, Voodoo is a tech company that creates mobile games and apps with a mission to entertain the world. Gathering 800 employees, 7 billion downloads, and over 200 million active users, Voodoo is the #3 mobile publisher worldwide in terms of downloads after Google and Meta. Our portfolio includes chart-topping games like Mob Control and Block Jam, alongside popular apps such as BeReal and Wizz.

Team

Our Consumer Apps teams are at the forefront of crafting innovative and engaging apps for daily enjoyment. Our ambition extends beyond gaming to entertain a global audience. Millions of people around the world, especially in the US, download and use the apps we create. You'll be working on Wizz, a social app specifically designed for teens, boasting over 3 million monthly active users in the US and UK. Wizz is a friend-finding and chat app where young people can safely express themselves and connect with like-minded peers in an authentic, pressure-free environment. Unlike other social media platforms that focus on followers, posts, or passive consumption, Wizz offers young people a space to have meaningful 1:1 conversations with peers. As a member of a high-performing team of 20, you'll collaborate to further scale and enhance Wizz, fostering a spirit of goodwill and creativity. As Wizz continues its dynamic growth and development, we are seeking an ambitious Senior Backend Engineer to join.

Role

We are looking for a Senior Backend Engineer who is not only technically strong but also eager to contribute to the product vision and actively participate in decision-making. You won’t just be writing code, you’ll have a key role in shaping the architecture, scalability, and long-term strategy of Wizz. Your ability to think beyond execution and take ownership will be crucial: we want someone who is proactive, challenges assumptions, and collaborates with product and engineering teams to create a robust, scalable, and innovative platform.

Your mission

• Own the backend architecture, ensuring scalability, performance, and reliability for millions of users.
• Collaborate closely with product teams to shape and influence product decisions with a strong technical perspective.
• Design, implement, deploy, and maintain highly scalable and available backend systems, including features that enhance user safety and content moderation.
• Integrate and manage third-party services (e.g., analytics, moderation, cloud tools) to ensure a secure and seamless user experience.
• Define and promote best practices in reliability, observability, and infrastructure management.
• Contribute to backend infrastructure evolution, ensuring that it supports rapid product iterations, responsible growth, and a safe environment for our users.
• Improve system performance and scalability, particularly around high-traffic distributed systems.

Our stack

• Language and libraries: Node.js, Fastify, Socket.io, Go, Firebase
• Databases: MongoDB, Redis
• Infrastructure: Cloud Run, Pub/Sub, S3, CloudFront, Big Query
• Ops: Github Action, AWS CLI, gcloud CLI, Docker, microservice architecture
• iOS: XCode, GitHub, Cocoapods (public and private)

Profile

• Passion for the mobile consumer industry
• Be fluent in French
• Excellent back-end programming skills (5+ years experience)
• Interest in Node.JS (vanilla)
• Professional GCP or AWS expertise
• Experience building APIs
• Experience with high traffic and distributed systems architectures
• Familiarity with services & technologies used in our Stack
• Track record with a social media application is a plus
• DevOps skills (Terraform, Cloud formation, …), are a plus

Benefits

• Competitive salary upon experience
• Swile Lunch voucher
• Gymlib (100% borne by Voodoo)
• Premium healthcare coverage SideCare, for your family 100% borne by Voodoo
• Wellness activities in our Paris office
• Unlimited vacation policy
• Remote days on Mondays, Tuesdays and Fridays

Voodoo just won the award for Best Office Space in France