Senior Software Engineer, Energy Billing

Reel; København; On-site; DKK 700,000 - 900,000; Full time

Benefits offered by this job

Base salary + warrant program

30 days paid holidays

Pension and health insurance

Parental leave

IT equipment budget

Office in central Copenhagen

Lunch provided

Monthly socials & offsites

EU relocation support

Job summary

Reel in Copenhagen is seeking a Software Engineer for billing to own and grow our next-generation energy billing platform. You’ll collaborate with our CTO and engineering team to deliver features that serve multiple markets and customers.

You’ll work with Elixir, Phoenix, LiveView, TypeScript, and Python on GCP, Postgres with TimeScale and BigQuery, building reliable, scalable systems and tooling that automate monthly settlements.

Qualifications

• Shipped production software and demonstrated ownership.
• Experience with billing, payments, or settlement systems.
• Strong focus on building reliable, scalable systems.
• Comfortable working independently and making decisions.
• Curious about AI tools improving team shipping.

Responsibilities

• Own energy billing tech: lead the work on expanding our billing platform.
• Expand into new markets: build integrations for new markets on top of the platform.
• Energy analytics: structure and expand financial data for analytics and reporting.
• Build the tools our team runs on: automate workflows and provide full visibility.
• Contribute to technical direction: code reviews and shaping how our tech evolves.

Skills

Backend development

Billing systems experience

Payments/Settlement systems

Reliability and scalability

Independent work

Tools

Elixir

Phoenix

LiveView

TypeScript

Python

PostgreSQL

TimeScale

BigQuery

GCP

Job description

About Reel

We are rethinking electricity to accelerate the transition to a carbon-free energy system.

Electricity is one of the biggest sources of carbon emissions globally, yet most green power sold on the market today fails move the needle toward decarbonizing electricity production.

Reel empowers companies to move beyond climate commitments and achieve real-world carbon reductions, by bridging the gap between renewable energy producers and consumers.

Join our mission-driven, cross-disciplinary team of developers, builders, and climate experts working to accelerate the transition to a net-zero economy.

How You Can Contribute

We’re working with some of the most exciting technologies within energy, delivering renewable power to corporates and balancing production from asset owners.

We’re optimizing solar parks, wind farms, and grid-scale batteries, trading across different markets and providing ancillary services to help stabilize the grid.

At the end of each month, we’re condensing all of this activity into a few numbers on an invoice for each of our customers. That’s only possible with a strong, purpose-built energy billing platform.

As our new Software Engineer for billing, you’ll own and grow our next-generation energy billing platform. You’ll work closely with Christian, our CTO, the rest of the engineering team, and our electricity operations team.

What Your Role Will Look Like

These are some (not all) of the things you will be working on:

• Own our energy billing tech: Lead the work on continually improving and expanding our billing platform to serve new products, collaborating closely with engineering colleagues.


• Expand into new markets: Every market has its own rules, data, and (more often than not) quirks we need to adapt to. You’ll build the integrations that allow us to serve new markets, building on top of the platform we have today.


• Energy analytics: Structure and expand our financial data for accurate and up-to-date customer analytics and reporting.


• Build the tools our team runs on: Our electricity operations team settles all of our customers every month. Build the tooling that gives them the full picture, catches anything that looks off, and makes their workflow as automated as possible.


• Raise the bar and help set the direction: Perform code reviews, share feedback with colleagues, contribute to key technical decisions, and be a core member of the team shaping how our tech evolves.

We think you will thrive in this role if

You have shipped production software and know how to get things done. You take real ownership of your work and have a bias for shipping. You don't need to know anything about energy today or have years of experience with energy billing - what matters most is that you're eager to learn and ready to put in the work.

You might also recognise yourself in some of these:

• You have solid experience building and maintaining backend systems in production.


• You have worked with billing, payments, settlement or other financial systems.


• You are comfortable being the person who cares whether a number is right.


• You care deeply about building reliable, scalable systems, while shipping frequently.


• You default to simple, pragmatic solutions.


• You work well independently, make decisions with confidence, and know when to bring others in.


• You enjoy sharing knowledge and helping others level up.


• You are curious about how AI tools can help us ship better software as a team.

We work in Elixir, using the Phoenix framework and LiveView + TypeScript for the front-end. We use Python for ML and trading. We're hosted on GCP, data in Postgres w. TimeScale and BigQuery. Experience in this stack is by no means a requirement - several engineers on the team today had no prior experience in Elixir.

Please note that we are located in Copenhagen, Denmark and this is an in-office role with flexibility for occasional hybrid work.

Working at Reel

At Reel, we care deeply about our people. We offer a workplace that values initiative, ownership and kindness, with ample room for personal and professional growth. We believe great teams are built by welcoming people with different backgrounds, perspectives, and lived experiences.

You will join a tight-knit team on an ambitious journey, where the impact of your role will be visible and recognisable on a daily basis. Every colleague - from founders to student assistants - are in this together. We cherish focus and autonomy just as much as team work and setting time aside for having fun together - at our monthly socials, bi-annual offsites and daily coffee chats in our bright and spacious office in central Copenhagen, 2 minutes from the metro.

What We Offer You

At Reel, we offer you an organisation that cares as much for its people as for the climate. We are committed to fostering an inclusive workplace where your personal growth and well-being is imperative.

• Compensation: A healthy base salary + warrant programme


• Vacation: 30 days (5 weeks + 1) of paid holidays to recharge


• Pension: Employer-supported pension scheme, including health insurance


• Parental leave: A generous parental leave policy


• Equipment: Choose your preferred IT setup (Mac, Windows, etc.) with a budget of 25,000 DKK


• Office: A vibrant office-first culture in central Copenhagen with a flexible remote work policy


• Lunch: A delicious lunch at the office every day - and your daily caffeine fix from our espresso machine


• Socials: Monthly social events and bi-annual offsites where we have fun, unwind, and nurture our team spirit


• Visa: We're only able to support relocation with an existing EU work visa for this role.

You don't feel like you fulfill all the criteria? We know that 'perfect' candidates do not exist. The only thing you need to ensure is that the problem we are solving at Reel is one you cannot wait to get out of bed for on Monday morning.

We encourage all candidates, regardless of age, gender, sexual orientation, ethnicity, religious beliefs, etc. to apply.