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# Staff Engineer - Fullstack JS/TS

- **Company:** lemlist
- **Location:** Paris, France
- **Experience:** Expert
- **Salary:** €75,000.0 - €90,000.0
- **Contract:** Temporary contract
- **Skills:** JavaScript (Programming Language), Software Bug Management, MongoDB, Node.Js, Software Engineering, TypeScript, Web Applications, ReactJS, Backend, Front End Software Development
- **Published:** October 31, 2026
- **Apply:** https://www.welcometothejungle.com/en/companies/lemlist/jobs/staff-engineer-fullstack-js-ts_paris

## About the Role

* You've shipped meaningful features in production
 * You've contributed to improving our codebase
 * You've brought knowledge to the team that made other people improve

Within 12 months

 * You've led delivery of multiple successful projects
 * You've had direct impact on scalability & performance
 * You've grown into your an internal reference on some technical topics and mentor others, Must have
 * 10+ years in Software Engineering
 * 7+ years in JavaScript/TypeScript (frontend + backend)
 * Solid skills in Node.js, React, MongoDB
 * Proven track record building & maintaining web apps
 * Always hungry to learn more
 * Autonomous, fast learner, and collaborative
 * Fluent in French & English, based in French timezone (+/- 2h)

Nice to have

 * B2B SaaS startup experience
 * Self-taught hacker or side-project builder
 * Passionate about experimenting & creating beyond work

## Description

We're looking for a Staff Engineer to join our team.

You'll design, build, and ship features across frontend and backend, improve performance, and progressively take leadership on more transversal topics, mentor peers, and drive delivery.

What you'll do

 * Build new features end-to-end (frontend + backend) by working hand-in-hand with a strong Product team
 * Improve the codebase (refactoring, bug fixes, optimization)
 * Collaborate with the rest of the team to solve technical issues
 * Mentor fellow developers, share knowledge, and raise the bar
 * Step up as Tech Lead on specific topics: drive quality, make technical choices, and align delivery
 * Solve difficult problems that impact 10,000s of customers every day, * See your impact quickly with a very short feedback loop
 * Work with senior engineers who love to learn and share knowledge
 * Remote-first culture (office in Paris if you prefer )
 * No endless meetings, high autonomy, big impact