9fin • London

Software Engineer (Backend)

Employment type:  Full time

Remote-first – No mandatory office days, use office as often as you wish

Core hours 10–3

Dog friendly

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Job Description

The world's largest asset class, debt, operates with the worst data.

Technology has revolutionized equity markets with electronic trading, quant algos and instantaneous news. However, in debt capital markets, the picture is completely different. It still behaves like it’s in the 1980s; trillions of dollars of trades are placed over the phone, news is slow, and corporate credit information is imperfect and scattered.

Our mission is to change this.

9fin's proprietary technology delivers fast and comprehensive financial, credit, legal & ESG analysis. Our clients are able to make faster, more informed decisions, win more business and most importantly, save time.

Our fast growing list of clients include 9 of the top 10 Investment Banks, leading Asset Managers, Hedge Funds and Law Firms.

Every day is different, but here's an example of the kind of things you'll work on:

  • This role is the opportunity to take on the technical leadership on projects, defining and designing systems, making quick proof of concepts and working closely with Product and our Clients.
  • Write code and lead others in the team in delivering new service functionality, implementing API’s, data routing/processing and automation mechanisms.
  • Development and engineering primarily on the backend services and web application hosted tools and systems of the 9fin platform.
  • Taking a leading role within project teams as a senior IC, running code reviews and mentoring of junior developers, involvement in early research and experimentation with new technologies providing input for new features and products.
  • Continually improve on the 9fin codebase taking the chance to automate, refactor and document when you can.
  • Variety: Our web platforms are incredibly diverse, from complex financial data modelling, capturing environmental, emission, energy data, incorporation of ML/AI prediction services, data visualisation serving and automation systems.
  • Collaboration and teamwork: Cross functional teams are formed for all projects including the appropriate domain expertise from 9fin financial, legal and editorial colleagues. This allows the best quality information and feedback to go directly to engineering project teams. Your ability to explain and break down complex projects to non technical audiences will enable productive and efficient team progress.
  • Developer Experience: Through managed automated preview environments, feature flags and well maintained non production environments. You will be able to move with velocity and get feedback and iterate quickly.

Our Backend Stack

  • Python is the dominant backend language used
  • Flask & FastAPI
  • Typing is used within our Python stack to power automated documentation and API definitions
  • Relational Databases (PostgreSQL) at the heart of majority of services
  • We’re AWS for Cloud hosted services
  • Heavy use of AWS lambda Serverless
  • Docker (AWS ECS) for uniform development/deployment from dev to prod


This role will be a great fit if you:

  • Can effectively plan and reason about your software, understanding where it fits into systems and the overall business
  • Can think about how data will pass through your software; from persistent storage through to API endpoint
  • Experience with Python and its web frameworks (we currently use Flask, and are moving to FastAPI with Typing)
  • Strong experience delivering APIs, Service Oriented Architecture
  • Good working knowledge of SQL statements for retrieving data
  • A good collaborator and communicator with cross functional engineering teammates and others within 9fin
  • Code Quality: Through writing testable, maintainable code, and by engaging in code review for your own work and for reviewing others


We’re a scaling start up and we enjoy sharing our success, when the company succeeds, we always reinvest that in our people. We also offer huge amounts of responsibility, an abundance of opportunity for growth and a platform to truly excel.

Financial & Insurance

  • Competitive Salary(our salary bands are benchmarked at the top end of the market)
  • Equity options
  • Pension (your minimum contributions are 4% with 9fin matching up to 7%)
  • Private Medical Insurance
  • Paid sick leave with Income Protection for long periods of illness
  • Group Life Assurance
  • Season Ticket Loan & Cycle to Work schemes

Time off

  • 25 holiday days per year
  • Local public holidays (with the ability to exchange them for alternative days)
  • Hybrid working model, to allow you the flexibility to decide how, where and when you do your best work
  • Work abroad for up to 3 months a year
  • 1 month paid sabbatical after 5 years of service
  • Enhanced parental leave & flexible working arrangements available

Training & Culture

  • Professional learning and development budget
  • Quarterly team socials
  • Summer and Winter company social events

9fin is an equal opportunities employer

Don’t meet every single requirement? At 9fin we are dedicated to building and promoting a fair and inclusive workplace where everyone can flourish, reach their full potential and truly belong. We recognise diverse teams allow a more creative and productive environment. So, if you’re excited about this role but your experience doesn’t perfectly align with the job description, we encourage you to apply anyway. You might just be who we’re looking for - for this role, or perhaps another.

Company benefits

Share options
Open to part-time employees
Health insurance – Vitality (lots of other perks!)
Enhanced maternity leave – 18 weeks full pay
Enhanced paternity leave – 4 weeks full pay
Work from anywhere scheme – work abroad for 3 months a year
Personal development budgets – £1250 a year to spend on L&D
Dental coverage
Matched pension contribution
Financial coaching – A 1:1 finance consultation with our benefits broker
Dog friendly office
Open to compressed hours
Hofy home office set up
Enhanced WFH tools
Mental health days
Compassionate leave
Women’s health leave
Enhanced sick pay
Enhanced sick days
Season ticket loan
Bank holiday swaps
Shared parental leave
Cycle to work scheme
Annual pay rises
Life insurance
Equity packages
Skilled worker visas
Employee assistance programme
L&D budget
Employees are very happy with their working location freedom
Employees are very happy with the flexibility in the hours they work
Employees are largely happy with the benefits their company offers
Work-life balance
Employees feel that they can switch off quite easily from work
Role modelling
Employees feel that flexible working is part of the culture
Employees feel they have complete autonomy over getting their work done

Additional employee ratings
(these do not contribute to the FlexScore®)

Employees feel that the diversity is good and there are continued efforts to improve it
Employees feel like the company culture is brilliantly inclusive and equitable
Employees feel like it is a really great environment to work in
Employees feel very excited about and aligned with the company mission
Employees feel that their salary is good and matches the value they bring

Working at 9fin

Company employees


Gender diversity (male:female)

63%M 37%F

Office locations

London, New York

Hiring Countries

United Kingdom
United States

Awards & Achievements

Most flexible companies

Most flexible companies

Flexa100 2024

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