About BMLL
BMLL is the leading independent provider of harmonised Level 3, 2 and 1 historical data and analytics across global equities, ETFs, futures and US equity options. We provide market participants with immediate access to granular T+1 order book data and advanced analytics, enabling them to accelerate research, optimise trading strategies, and better understand market behaviour.
BMLL was acquired in 2025 by Nordic Capital, alongside minority shareholder Optiver, marking a joint commitment to accelerate the company’s next phase of growth.
We offer an inclusive and collaborative culture, a hybrid working environment that includes regular days in our London office, weekly team lunches, and a variety of out-of-hours social activities.
For more information, visit our website or follow us on X (@bmlltech) and LinkedIn @BMLL.
About the Role:
At BMLL, we process financial data in a process we call parsing. We continually add new financial datasets to our platform whilst upgrading and improving existing ones. Parsing occurs in well-defined data pipelines built using a distributed architecture. The engineering of the pipeline is as important as the data transformation process, and we are constantly working to improve its performance and reliability. We curate the data to ensure the highest quality of delivery to our customers. Every day, we consume 600GB of new data across 750,000 securities to deliver into our platform, our dashboard products and data services. These are accessed by our customers who are dependent on our services for their own workflows.
We are looking for a strong C++ Developer to join a small team who engineers the market and analytics data products. As part of our technology strategy, you will design and develop the next generation of our analytics data products, This is a crucial part of our roadmap. You will also improve the process and reliability of managing these large datasets using the latest AWS technologies and become an expert in understanding the data and the way we curate and process it.
This is an opportunity to join a cutting-edge FinTech company with the potential to grow your technical, finance and cloud & data engineering skills.
Responsibilities:
- Owning the full scope of assigned development projects for market data and analytics data products, including liaising with the business to gather requirements, designing the solution with the team, and building and delivering completed functionality to production
- Delivering new data products using C++
- Migration of Python data products into C++ to drastically improve performance
- Helping to drive improvements in all areas, including the parsing framework, data quality, testing and CI
- Understanding the data, how it reaches BMLL, how we process it and deliver it to customers
- Communicating with technical teams both within BMLL and sometimes at data providers such as financial exchanges
- Some second-line support of the data product processes and the data, shared amongst the team.
Requirements
Essential:
- Experience working with financial data or other large datasets
- Industry experience in writing production-level Modern C++ (C++20 or later) and delivering functioning, well-tested systems.
- Industry experience with Python
- Industry experience in developing on a Linux platform
- Industry experience in delivering production-grade systems using modern development practices — including source control, unit testing, and CI/CD pipelines for automated build, test, and deployment.
- Experience with agile development practices
- Ability to self-organise and deliver a project over a period of up to a few months
- Strong problem-solving skills
- Strong communication skills
- Computer science or other STEM degree
Desirable:
- Snowflake
- AWS
- NumPy, Pandas, Polars
- Airflow
- Parquet
Benefits
- Competitive salary
- 25 days holiday plus bank holidays
- Discretionary Bonus
- Pension Scheme
- Private Medical Insurance
- Work remotely abroad for up to 40 business days each year
- Life Insurance
- Combination of remote and London based office working, with 2 days in the office per week.
- A yearly Well being Physical Activity budget
- Continuous learning through funded training and challenging projects
- Collaborative culture
- Weekly team lunches
- Free Fruit, snacks, and drinks provided throughout the day (When office based)
- Regular Team Socials
- Cycle to Work Scheme
We are an inclusive employer and welcome applicants from all backgrounds. We pride ourselves on our commitment to Equality and Diversity. We are committed to removing barriers throughout our hiring process. If you have any special requirements or require reasonable adjustments to help you access career opportunities at BMLL, please do let us know [email protected].
Top Skills
BMLL London, England Office
168-172 Old Street, London, United Kingdom, EC1V 9


