At a Glance
- Tasks: Own the ecommerce journey, building backend systems for payments and seller tools.
- Company: Join Fleek, a fast-growing startup transforming the secondhand fashion market.
- Benefits: Competitive salary, equity options, and a chance to make a real impact.
- Other info: Be part of a dynamic team in a rapidly scaling environment.
- Why this job: Tackle unique challenges with AI while contributing to sustainability in fashion.
- Qualifications: 6-10 years of backend experience, ideally with Node.js and TypeScript.
The predicted salary is between 100000 - 140000 £ per year.
Fleek is a ~$50M Series B startup backed by a16z and Y Combinator, building the AI-native infrastructure for the $350B global secondhand fashion market.
You will join the Growth squad to own the core ecommerce journey, building backend systems for discovery, payments, and seller tools. Reporting to the CTO, you'll integrate the proprietary FleekSort AI classification engine into a marketplace handling millions of items. This role is about digitizing a broken, manual supply chain at global scale.
Location: London, UK
Why this role is remarkable:
- Work on a genuinely novel technical challenge by integrating FleekSort, a custom AI model (not a GPT wrapper) that digitizes opaque secondhand inventory.
- Join a hyper‑growth company tripling year‑on‑year with ~$50M in funding from top‑tier investors like a16z, Y Combinator, and HV Capital.
- Deliver massive environmental impact by building systems that have already saved 9 million items from landfills and are scaling to serve thousands of global retailers.
What You Will Do:
- Architect and own the end‑to‑end ecommerce journey, including item discovery, search, multi‑currency payment systems, and credit infrastructure.
- Design and scale backend services to handle over 1 million unique items per month, connecting AI grading engines to real‑time marketplace workflows.
- Collaborate in a senior product squad to translate complex international logistics and supply chain challenges into reliable, high‑performance software.
The ideal candidate:
- Has 6‑10 years of professional backend experience, ideally using Node.js and TypeScript, with a proven track record of shipping high‑traffic production systems.
- Possesses a product engineering mindset from a consumer‑facing marketplace or fintech background, focusing on commercial outcomes rather than just infrastructure.
- Thrives in early‑stage, fast‑paced environments (Seed to Series B) and utilizes AI tools like Cursor or Copilot as a force multiplier in their workflow.
Senior Backend Software Engineer (£100k–£140k + Equity) at Fleek employer: Jack & Jill
Fleek is an exceptional employer, offering a dynamic work environment in the heart of London where innovation meets sustainability. As a rapidly growing startup backed by top-tier investors, employees have the unique opportunity to contribute to meaningful projects that digitise the secondhand fashion market, while enjoying competitive salaries, equity options, and a culture that fosters collaboration and personal growth.
StudySmarter Expert Advice🤫
We think this is how you could land Senior Backend Software Engineer (£100k–£140k + Equity) at Fleek
✨Join Local Tech Meetups
Get out there and mingle with fellow developers by joining local tech meetups. It’s a fantastic way to meet people who might be working at Jack & Jill or know someone who does. Plus, you can pick up some trendy tech skills and trends while you're at it!
✨Contribute to Open Source Projects
Show off your coding chops by jumping into open-source projects. Not only does this give you practical experience, but it also gets you noticed in the dev community. You'll create a killer portfolio that speaks volumes about your skills to Jack & Jill.
✨Tap into Online Developer Communities
Don’t underestimate the power of online developer communities like GitHub, Stack Overflow, and even Reddit. Participate in discussions, share your projects, and build your visibility. We can often find opportunities through these channels that can lead to a full-time gig at companies like Jack & Jill.
✨Explore Job Boards Specifically for Tech Roles
Keep your eyes peeled on job boards that focus on tech roles. Sites like TechCareers or Stack Overflow Jobs can often have listings for companies like Jack & Jill that might not show up on broader job sites. Make it a habit to check these regularly, and don’t hesitate to apply directly through our website!
We think you need these skills to ace Senior Backend Software Engineer (£100k–£140k + Equity) at Fleek
Some tips for your application 🫡
Show off your coding skills:When applying for a software engineering role, it's super important to showcase your coding skills. Make sure your CV includes your tech stack, any relevant programming languages you’re comfortable with, and examples of projects you've worked on. If you have a GitHub profile, link it up! We love to see code in action.
Tailor your portfolio:For a full-time role, we’d expect to see some solid examples of your work in your portfolio. Make sure to include at least two or three projects that highlight your problem-solving skills and your ability to work with different technologies. Focus on the projects that are most relevant to the position at Jack & Jill.
Craft a killer cover letter:Your cover letter is your chance to stand out—make it personal! Explain why you want to work at Jack & Jill and how your skills align with the role. Show us your passion for software development. We dig enthusiastic candidates who understand the value of collaboration and continuous learning!
Be clear and concise:When it comes to writing your CV and cover letter, clarity is key. Avoid jargon that could confuse us and stick to simple, direct language. Highlight your achievements with quantifiable results where possible, and keep everything easy to read. A well-organised application goes a long way!
How to prepare for a job interview at Jack & Jill
✨Brush Up on Your Coding Skills
For a full-time software engineering role, it's crucial that we stay sharp with our coding abilities. Expect technical questions that might involve solving problems on the spot or discussing algorithms. Practise on platforms like LeetCode or HackerRank to get comfortable with the types of questions that often come up.
✨Know Your Tools and Frameworks
Make sure we’re well-acquainted with the tools and technologies listed in the job description. Familiarise ourselves with any specific frameworks or programming languages mentioned. If Jack & Jill uses React or Node.js, for instance, be ready to discuss how we’ve used them in previous projects or coursework.
✨Showcase Your Projects
Bring along a portfolio that highlights our best work. This could be code samples, GitHub repositories, or any side projects we’ve built. Make sure we can talk through our thought process for each project, especially the challenges we faced and how we solved them—this shows our problem-solving skills in action.
✨Prepare for Behavioural Questions
While technical skills are key, full-time positions also require cultural fit. Be ready to discuss our previous experiences and how we handle teamwork, conflict, and deadlines. Brush up on the STAR method—Situation, Task, Action, Result—to clearly articulate our past experiences when discussing how we've contributed to a team.
