(C# / .NET, Objective-C / iOS, Android / Java)

We are looking for a developer with broad knowledge and breadth of skills to join our development team. The team is responsible for the continued advancement of NMI’s ChipDNA POS framework solutions including but not limited to: integrations with point-of-sale PIN pads, interfaces for customers, bespoke solutions, storage and processing of transaction data, software security.

The ideal candidate will have experience in C# or Java, but candidates with experience in other object-oriented languages will be considered. The projects for which the developer will participate will vary within the areas for which the development team is responsible, but will primarily be focused around the integrating PIN pads and card readers into ChipDNA SDKs for the processing of card based transactions. These transactions come in the form of manually keyed transactions, magnetic swipe transactions, contactless and full Chip-and-PIN transactions. It is necessary to use a combination of the data that we receive from integrators, devices and databases, build the correct messages, send them for processing, and manage the response with all associated error conditions. Consideration also has to be given to performance, availability and reliability.

About Us

NMI develops the most trusted payment software for mobile, online and in-store that is relied on in 38 countries, 24 hours a day, 365 days a year. With offices in Bristol, New York, Chicago and Salt Lake City, our payment technology powers millions of customers worldwide, ensuring they can take payments worth billions, securely and reliably.

You’ve probably used our software when ordering a burger, shopping online or booking a train ticket – without realising it! If you are passionate, talented, ambitious and want to join a team of industry leading experts to drive our continued development, we want to hear from you!

Check out more about working for us here:


What will I be doing?


  • Development and support of our point-of-sale frameworks and tools
  • Development and support of internal processes relating to different aspects of payment
  • Development and support of other applications required for the companies procedures
  • Part of the team that assists our Customer Support desk with escalated customer queries and issue resolution.

Do I have what it takes?

Essential Skills & Experience

  • Understanding of C#, Java or another object-oriented language
  • Common development environment such as Visual Studio, Android Studio, Xcode, Eclipse etc.
  • Attention to detail in all aspects of development
  • Good communication skills; both written and verbal for dealing with suppliers and project partners

Preferred Skills & Experience

  • An understanding of networking principles and protocols such as sockets, HTTPS, DNS and SSL
  • Understanding of Secure Programming Practices
  • Knowledge of SQL
  • Understanding of cryptography and its application in different areas
  • Version control in a multi-user environment
  • Experience in Continuous Integration systems (e.g. TeamCity)


As well as being a part of something exciting everyday, you will also receive the following benefits:

  • Annual salary of up to £27,000 (dependant on experience)
  • 25 holiday days each year (+ bank holidays + 1 day after each year of service with up to a max. of 30 days)
  • Work-life balance with our Flexi-time policy
  • 7 hours per day, 35 hours per week
  • Annual bonus scheme
  • A chance to develop with an allocated company training budget
  • Private health insurance
  • Bike2Work Scheme (government-backed cycle to work scheme)
  • Stakeholder pension scheme
  • Perkbox subscription – discounts on gyms, restaurants, high st retailers, cinema tickets etc
  • Free fruit delivered to the office
  • Great central BS1 location with one of the best views in Bristol!

We’re looking for creative and passionate people who share our vision of making payments easy. If that sounds like you and you meet the requirements above, then get in touch!

Please be aware that all offers of employment are made subject to receipt of satisfactory background and financial checks.

Please be aware that NMI does not operate a licence for the sponsorship of those who are not already eligible to work within the UK. Unfortunately, therefore we cannot process any application from individuals unable to provide documentary evidence of their eligibility to commence work in the UK. For further information on the necessary eligibility documents please click here:

Job details


Skills required

iOS (Objective-C)

Perks & benefits

Flexible Working
Private Health
Bike Loan
Performance Bonus
Subsidised Learning
Good Pension
Volunteering Days
Free Food