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# Technical Lead - Fullstack JS/TS

- **Company:** lemlist
- **Location:** Paris, France
- **Experience:** Expert
- **Salary:** €65,000.0 - €75,000.0
- **Contract:** Temporary contract
- **Skills:** JavaScript (Programming Language), Software Bug Management, Software as a Service, MongoDB, Node.Js, Performance Tuning, TypeScript, Web Applications, ReactJS, Backend, Front End Software Development
- **Published:** October 29, 2026
- **Apply:** https://www.welcometothejungle.com/en/companies/lemlist/jobs/technical-lead-fullstack-js-ts_paris

## About the Role

Must have

 * 8+ years in TypeScript / JavaScript (frontend + backend)
 * Solid skills in Node.js, React, MongoDB
 * Proven track record building & maintaining web apps
 * Always hungry to learn more, particularly around JS/TS
 * Autonomous, fast learner, and collaborative
 * Fluent in French & English, based in French timezone (+/- 2h)

Nice to have

 * B2B SaaS startup experience
 * You worked on a SaaS that scaled massively
 * You are familiar with advanced performance optimization
 * Self-taught hacker or side-project builder
 * Passionate about experimenting & creating beyond work

## Description

We're looking for a Tech Lead or a Senior Fullstack TypeScript Developer to join our team.

The role starts as a Senior Developer, then evolves into a Tech Lead position after 3-6 months, once you've proven yourself in the squad.

You'll design, build, and ship features across frontend and backend, improve performance, and progressively take leadership within your squad to set technical standards, 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 in your squad: drive quality, make technical choices, and align delivery

What success looks like

Within 3 months

 * You're fully onboarded and comfortable in our stack
 * You've shipped meaningful features in production
 * You've contributed to improving our codebase

Within 6 months

 * You've led delivery of multiple successful projects
 * You've had direct impact on scalability & performance
 * You've grown into your Tech Lead role and mentor others

What's in it for you

 * Join a bootstrapped, profitable, fast-growing SaaS company
 * Build products used by thousands of businesses worldwide
 * 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