Application Guide

How to Apply for Backend Engineer

at Octopus Energy

🏢 About Octopus Energy

Octopus Energy is redefining the energy sector with a focus on transparency, AI, and renewables to drive a low CO2 future. They are known for their innovative technology and customer-centric approach, making energy simpler and more accessible. Working here means contributing to a mission-driven company that values engineering excellence and rapid iteration.

About This Role

As a Backend Engineer, you will directly impact customer experience through rapid feedback loops and develop innovative tech solutions to simplify energy. You'll work on backend systems to integrate new features and optimize services, using Python, Django, and modern tools like GraphQL and Celery.

💡 A Day in the Life

A typical day might start with a stand-up to discuss progress on integrating a new feature for customer billing. You'll then write Python/Django code for a new GraphQL endpoint, review a colleague's PR, and debug a Celery task that handles async meter readings. In the afternoon, you might collaborate with the frontend team on API design and deploy changes using Terraform and AWS.

🎯 Who Octopus Energy Is Looking For

  • Has 2-4 years of backend development experience with Python and Django or equivalent web frameworks.
  • Strong in domain modeling, building robust and fault-tolerant software, and experienced with REST and GraphQL APIs.
  • Proficient with Celery for async tasks and PostgreSQL for data persistence.
  • Nice-to-have: experience with AWS, Terraform, Packer, Consul, React, or Next.js, showing DevOps and full-stack awareness.

📝 Tips for Applying to Octopus Energy

1

Highlight your Python and Django expertise with specific projects or contributions (e.g., GitHub repos or past work).

2

Showcase experience with GraphQL and REST APIs, including designing scalable endpoints and handling errors.

3

Demonstrate understanding of Celery and async processing by describing a project where you managed background tasks.

4

Mention any cloud infrastructure experience (AWS, Terraform) even if not required, as it's a plus.

5

Tailor your cover letter to Octopus Energy's mission: emphasize your interest in renewable energy and transparency.

✉️ What to Emphasize in Your Cover Letter

['Your passion for using technology to solve real-world problems, especially in energy and sustainability.', 'Specific examples of building robust backend systems with Python/Django and handling high-load scenarios.', 'Experience with GraphQL and REST APIs, and how you ensured reliability and performance.', "Alignment with Octopus Energy's values of transparency, innovation, and customer impact."]

Generate Cover Letter →

🔍 Research Before Applying

To stand out, make sure you've researched:

  • Read Octopus Energy's blog or tech talks about their platform and engineering culture.
  • Understand their product offerings, especially how they use AI and data to improve energy services.
  • Look into their approach to renewables and CO2 reduction to align your application with their mission.
  • Check their GitHub or open-source contributions to see their tech stack and coding standards.

💬 Prepare for These Interview Topics

Based on this role, you may be asked about:

1 Design a scalable API for managing energy consumption data (GraphQL vs REST trade-offs).
2 How would you handle a spike in async tasks with Celery? Discuss concurrency and error handling.
3 Explain your experience with PostgreSQL: indexing strategies, query optimization, and migrations.
4 Describe a time you built a fault-tolerant system. How did you handle failures and ensure data consistency?
5 How would you integrate with external energy providers? Discuss API design and security considerations.
Practice Interview Questions →

⚠️ Common Mistakes to Avoid

  • Not demonstrating knowledge of Python/Django specifics; generic backend experience won't suffice.
  • Ignoring the company's mission; this role is at an energy company, so show interest in sustainability.
  • Overlooking the 'fault-tolerant' requirement; failing to discuss error handling or robustness in your experience.

📅 Application Timeline

This position is open until filled. However, we recommend applying as soon as possible as roles at mission-driven organizations tend to fill quickly.

Typical hiring timeline:

1

Application Review

1-2 weeks

2

Initial Screening

Phone call or written assessment

3

Interviews

1-2 rounds, usually virtual

Offer

Congratulations!

Ready to Apply?

Good luck with your application to Octopus Energy !