Senior Software Engineer- Python

We’re looking for a Senior Software Engineer to join Humboldt and help shape Asset Backed Trading as it grows into new countries and capabilities.

You will work in a Python monorepo of serverless services: event driven pipelines that ingest market and asset data, build optimisation problems, call solvers, and write dispatch and trading positions back out. You will also help evolve the interfaces with other Flex services and APIs that Asset Backed Trading depends on.

Owning production systems that have to be correct, not just available

Shaping a young service

Designing event driven architectures (queues, events, lambdas, APIs) that stay understandable as they grow

Turning messy domain rules into clear models, interfaces and tests

Working through new problems at the intersection of software architecture and energy systems modelling

Pairing with specialists (traders, data scientists, platform) without needing to be an expert in their field on day one

Raising the bar across software (typing, testing, observability, tooling, and thoughtful refactors), tooling, and ways of working

Design, build and operate the Python backend services behind Asset Backed Trading

Own event driven flows from trigger to dispatch: queues, lambdas, events, and the Flex API integrations around them

Productionise new algorithms and market capabilities, working closely with data scientists so prototypes become reliable services

Help with team discovery for new epics, spanning software architecture and energy systems modelling

Improve reliability, latency, and operability through testing, monitoring, alarms, and careful refactoring

Contribute to infrastructure as code (CDK / CloudFormation) and deployment pipelines

Take part in architectural decisions as we grow Asset Backed Trading across EU markets and asset types

Support teammates through pairing, reviews, and shared problem solving

Help keep a high bar for typed, well tested Python in a domain where silent mistakes are expensive

We don’t expect everything, but experience in several of these areas will help.

Core skills

Strong Python experience

Experience building and operating backend services in production

Comfort with cloud platforms, ideally AWS (Lambda, API Gateway, SQS, EventBridge, DynamoDB, S3)

API design and domain modelling for complex business workflows

Writing robust, typed, well tested code (pytest, CI, 100% branch coverage, a real interest in catching bugs before production)

Strong communication and collaboration with both engineers and non engineers

Judgement in ambiguity: you can make trade offs explicit and keep delivery moving

Nice to have / especially relevant

Experience in problem solving, modelling, optimisation.

Event driven or serverless architectures at meaningful scale

Infrastructure as Code (CDK, CloudFormation, or Terraform)

Experience with Pydantic, strict typing, and mypy

Observability in production (CloudWatch, Grafana)

Exposure to energy, trading, optimisation, or other constraint heavy domains

Working in a monorepo with shared libraries and multiple deployable services

You do not need a background in energy or mathematical optimisation. Curiosity about the domain and a willingness to learn from traders and data scientists matters more than arriving with grid expertise.

Backend and services

Python 3.13, uv, Pydantic

AWS Lambda, API Gateway, SQS, EventBridge, DynamoDB, S3

pytest, mypy, ruff in CI

Mixed Integer Linear Programs for expressing energy storage problems (owned with data science; we integrate with the solver)

Infrastructure and tooling

AWS CDK (TypeScript) and CloudFormation

aws-lambda-powertools for observability

CI/CD via AWS CodePipeline

Grafana dashboards and CloudWatch alarms

Product and analysis

Databricks SQL, dashboards and notebooks for reporting

Jupyter, numpy, pandas, plotly for investigation

Cursor, Copilot, and a healthy amount of custom scripting

Small, highly collaborative team with high trust and high ownership

No blame: we learn from mistakes by improving systems and process, not by finding fault

Optimise for impact on users

Pair when it helps, work independently when it does not

Sustainable pace

Ship quickly without dropping quality: small PRs, fast iteration, quality built in from the start

Are you ready for a career with us? We want to ensure you have the right tools and environment to unleash your potential. If you have any accommodation requests, please contact us at inclusion@kraken.tech. We’ll do our best to tailor the experience to your needs so you can feel comfortable, confident and be at your best!

Studies have shown that some groups of people, like women, are less likely to apply to a role unless they meet 100% of the job requirements. Whoever you are, if you like one of our jobs, we encourage you to apply as you might just be the candidate we’re looking for! At Kraken, we're creating a team of genuine, honest, empathetic people. Our people are our strongest asset and the unique skills and perspectives people bring to the team are the driving force of our success. As an equal opportunity employer, we do not discriminate on the basis of any protected attribute. We consider all applicants without regard to race, colour, religion, national origin, age, sex, gender identity or expression, sexual orientation, marital or veteran status, disability, or any other legally protected status.

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Please note that, in line with our current recruitment policy, we are unable to offer visa sponsorship for this position; applicants must have the right to work in the country that they're applying to, at the time of application.*