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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 90000 - 120000 £ 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 employer: HartleyCo
Contact Detail:
HartleyCo Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Senior Software Engineer
✨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 when you're aiming for that Senior Software Engineer role.
✨Tip Number 2
Show off your skills! Consider building a small project or contributing to open-source that showcases your expertise in Python and TypeScript. This not only demonstrates your technical abilities but also your passion for coding.
✨Tip Number 3
Prepare for the interview by understanding the startup's product and market. Be ready to discuss how you can directly impact their growth and culture. We want to see that you’re not just looking for a job, but are genuinely excited about being part of their journey.
✨Tip Number 4
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 the initiative to engage with us directly.
We think you need these skills to ace Senior Software Engineer
Some tips for your application 🫡
Show Your Passion: When you're 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 is tailored to highlight 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 this.
Craft a Compelling Cover Letter: Your cover letter is your chance to tell us why you’re the perfect fit for this role. Share specific examples of how you've taken ownership in previous positions and how you can contribute to shaping our engineering culture.
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 Inside Out
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.
✨Showcase 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 position and potential challenges shows that you're not just a coder but someone who understands the bigger picture and can contribute to strategic discussions.
✨Ask Insightful Questions
Prepare thoughtful questions about the company's vision, product roadmap, and team dynamics. This demonstrates your genuine interest in the role and helps you assess if the company aligns with your career goals.
