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For Companies At a Glance
- Tasks: Join a founding team to build and scale innovative software products.
- Company: Exciting YC-backed startup in London with serious market traction.
- Benefits: Competitive salary, equity, hybrid working, and direct impact on product direction.
- Why this job: Be part of a dynamic team shaping the future of tech from day one.
- Qualifications: Strong experience in Python, TypeScript, and modern front-end frameworks.
- Other info: Perfect for builders who thrive in fast-paced, early-stage environments.
The predicted salary is between 78000 - 108000 £ per year.
This founding team role offers £90 K–£120 K plus equity. I’m working with an exciting YC‑backed startup in London that’s just closed a multi‑million‑pound funding round and is looking for a Senior Software Engineer to join their founding engineering team. Despite being early‑stage, they’re already punching well above their weight – with paying customers onboarded and serious traction in their market. This is a rare opportunity to get in at the ground floor of something special.
Responsibilities
- Working directly alongside the founders to build and scale the product
- Taking real ownership over technical decisions and architecture
- Shaping the engineering culture and technical direction from day one
- Building features that directly impact paying customers
Tech Stack
- Python
- TypeScript
- React/Next.js
Benefits
- 3 days per week in their London office (hybrid working)
- Direct impact on product and company direction
- Work with world‑class founders backed by Y Combinator
Qualifications
- Strong commercial experience with Python and TypeScript
- Experience with React/Next.js or similar modern front‑end frameworks
- Someone who thrives in fast‑paced, early‑stage environments
- A builder who wants ownership, not just tickets to complete
If you’re a senior engineer looking to step into a founding team role at a startup with genuine momentum, let’s talk.
Location & Employment
London, United Kingdom
Full‑time, Mid‑Senior level
Senior Software Engineer in London employer: HartleyCo
Contact Detail:
HartleyCo Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Senior Software Engineer in London
✨Tip Number 1
Network like a pro! Reach out to your connections in the tech industry, especially those who might know someone at the startup. A warm introduction can make all the difference in landing that interview.
✨Tip Number 2
Show off your skills! Create a portfolio or GitHub repository showcasing your projects, especially those using Python and TypeScript. This gives you a chance to demonstrate your expertise and passion for building.
✨Tip Number 3
Prepare for the interview by understanding the company's product and market. Research their tech stack and think about how you can contribute to their growth. Tailor your answers to show you're not just a fit, but the perfect fit!
✨Tip Number 4
Don’t forget to apply through our website! It’s the best way to ensure your application gets seen by the right people. Plus, we love seeing candidates who take that extra step to connect with us directly.
We think you need these skills to ace Senior Software Engineer in London
Some tips for your application 🫡
Show Your Passion: When writing your application, let your enthusiasm for the role and the company shine through. We want to see that you’re genuinely excited about joining our founding team and making a real impact.
Tailor Your CV: Make sure your CV highlights your experience with Python, TypeScript, and React/Next.js. We’re looking for someone who thrives in fast-paced environments, so showcase any relevant projects or roles that demonstrate your ability to adapt and build.
Craft a Compelling Cover Letter: Use your cover letter to tell us why you’re the perfect fit for this Senior Software Engineer role. Share specific examples of how you’ve taken ownership of technical decisions and contributed to product development in previous positions.
Apply Through Our Website: We encourage you to apply directly through our website. It’s the best way for us to receive your application and ensures you don’t miss out on any important updates from our team!
How to prepare for a job interview at HartleyCo
✨Know Your Tech Stack
Make sure you’re well-versed in Python, TypeScript, and React/Next.js. Brush up on your knowledge of these technologies and be ready to discuss how you've used them in past projects. This will show that you can hit the ground running and contribute from day one.
✨Show Your Ownership Mindset
This role is all about taking ownership, so come prepared with examples of how you've taken charge of projects or made significant technical decisions in your previous roles. Highlighting your ability to shape engineering culture will resonate well with the founders.
✨Understand the Startup Landscape
Research the startup's market and competitors. Being able to discuss their product and how it fits into the industry will demonstrate your genuine interest and help you stand out as a candidate who’s not just looking for any job, but specifically this opportunity.
✨Ask Insightful Questions
Prepare thoughtful questions that reflect your understanding of the company’s goals and challenges. Inquire about their vision for the product and how they see the engineering team evolving. This shows that you’re not just focused on the role, but also on the bigger picture.