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Pi Labs
Pi Labs

Junior Software Engineer



Software Engineering
Posted on Wednesday, March 13, 2024

Junior Software Engineer

Job Description

Application deadline: 2nd April 2024
Target start date: May 2024
Location: Hybrid with co-working space in Clerkenwell, London, UK / UK remote considered
Hours: Full time with core hours 10am - 4pm
Origination: New role
Language: English
Salary range: 30-40k

Meet Kestrix: the ‘Google Maps of Heat Loss’

Globally, 10% of emissions come from heating and cooling buildings, and nearly 6 retrofits must happen every minute between now and 2050 for net zero targets to be met. Luckily, tech (like good old insulation) to fix the problem exists. But when resources required for such a herculean undertaking – labour, financial, time – are limited, how can we be sure we are starting with the right buildings? Allocating the right budgets? Doing the work well?
Today, we can’t. That’s right: there is no scalable, cost-effective way of knowing reliably how heat is lost across the millions of buildings we all live, work, and play in – let alone how to fix it and how much fixes will cost. This leads to bottlenecks – lost time, wasted resources, and overspent budgets for those executing on building decarbonisation projects now – like housing providers, local governments, contractors, and energy companies.
Kestrix is here to solve retrofit’s data problem, enabling the world to retrofit its buildings at speed and scale. How are we going to do this?
We are building retrofit’s data layer. The ‘Google Maps of Heat Loss’, Kestrix uses thermal drones and AI to construct 3D heat loss models of buildings and reveal retrofit opportunities in seconds, without needing site visits. Our dataset is already streamlining planning, prioritisation, and verification of retrofits not just for single homes, but for hundreds (and soon thousands) of buildings in the portfolios of leading social housing providers.
We’ve raised over $1M in equity and grant funding, and are now looking for a savvy, hungry junior software engineer ready to apply their skills to helping bring Kestrix to the next level in our technological growth journey.
So what are you waiting for?
I hope to see your application.
Best wishes
CTO, co-founder & hiring manager

The role

Kestrix is growing its team off the back of recent funding wins.
We’re looking for a junior software engineer as part of our growing platform team, reporting to CTO and co-founder Matt.
A successful candidate is a self-starter, passionate about applying their software skills to solve the urgent problem of building decarbonisation in a fast paced and dynamic startup environment.

Our Values

At Kestrix, we work by 5 guiding principles:
🔍 We are curious. We ask questions (of customers and each other) and really listen to answers.
📏We are problem-solvers. We embrace an experimental approach to work. Fail, learn, adapt.
🤝We are generous. We go out of our way to help others and always look out for one another.
🌈We are respectful. We value others’ time, as well as opinions, and treat others respectfully.
👭We trust each other. We assume good intent, focus on output, and see mistakes as learnings.

Job Responsibilities

Develop new features in our GraphQL API that is the key connection point between the Kestrix user interface and our core platform. This API is expected to evolve into our customer facing API.
Develop software tools that maximise the velocity of our whole engineering team, and the quality of our product including in test automation and data management.
The role could evolve to also take on responsibilities in CI/CD, Dev Ops and ML Ops.
Collaborate closely with the rest of Kestrix’s engineering team
Participate in the design and architecture discussions, contributing your ideas and insights to ensure the scalability, reliability, and performance of the software.
Implement and maintain data processing pipelines, integrating external data sources, and ensuring the efficient flow of information between different components of the system.
Write clean, efficient, and maintainable code, following industry-standard software engineering practices.
Conduct thorough testing, debugging, and troubleshooting of the software, identifying and resolving any issues or bugs that arise.
Contribute to continuous integration and continuous deployment (CI/CD) practices, ensuring the smooth delivery and deployment of new features and updates.

Your Qualifications/Experience

Critical requirements

2 years of Python development experience.
Solid understanding of software engineering principles, including object-oriented programming, data structures, algorithms, and design patterns.
Ability to quickly learn and adapt to new technologies.
Experience with software development tools and practices, including version control (e.g. Github), agile methodologies, and issue tracking systems (e.g. Jira).
Knowledge of databases and SQL, with the ability to design and optimise database schemas.
Understanding of software testing principles.
Understanding of CI/CD processes and tools
Strong problem-solving skills and the ability to work independently and as part of a team in a fast-paced startup environment.
Excellent communication skills, with the ability to effectively collaborate and communicate technical ideas to both technical and non-technical stakeholders.

Nice to haves

Experience with Python development in a commercial environment
Experience in developing GraphQL APIs
Experience deploying and managing runtime environments in Google Cloud Platform.


25 days paid time off, the week between Christmas Day and New Years (with flexibility to shift for those of non-Christian religious backgrounds), and a day off on your birthday.
Hybrid working with 2 days per week at our co-working space in Clerkenwell, London.
Pension contributions (3% of salary)
Flexible working outside core working hours
Optional monthly team socials

Interview Process

The process will have 3 rounds, the outcome of each will be assessed by Kestrix who will notify you of the outcome by email:
Application form and CV submission here
1: First round interview with hiring manager (30 mins)
2: Role-specific case study (in-person)
3: Interview with other co-founder
Offer & take up 2 references