NMI

Payments

SeniorSoftwareEngineer

£48–58k United Kingdom Remote Friendly
Market Sentiment
HIGH DEMAND

Neural analysis suggests this role is
optimal for Senior candidates.

The Brief

“Senior Software Engineer at NMI. Skills: Backend development, Mobile SDK development, Payment solutions. Design SDKs. Develop SDKs”

Industry & Context.

Payments
Problems you'll solve

Problem-solving; Anticipate issues; Proactively address issues

Eligibility Requirements

Out-of-hours on-call rota

What They're Looking For.

Must Have

5 years of experience, Bachelor's degree in Computer Science, Equivalent experience

Nice to Have

C# proficiency preferred, Advanced proficiency in Java preferred

What You'll Do.

Design backend components

Develop backend components

Maintain backend components

Lead architectural discussions

Lead design discussions

Collaborate with Product

Collaborate with Operations

Mentor junior engineers

Mentor mid-level engineers

Participate in CI/CD evolution

Participate in deployment automation

Ensure code adherence

Ensure system adherence

Investigate performance issues

Resolve performance issues

Contribute to initiatives

How You'll Work.

Team & Collaboration

Cross-team initiatives; Product collaboration; QA collaboration; Operations collaboration

Communication Scope

Explain technical concepts

Process & Methodology

Agile methodologies

Full Job Description

NMI is a leading provider of payment gateway solutions, specializing in card-present solutions and payment processing. Our innovative technologies empower businesses to securely accept payments and optimize transaction processes. With a focus on reliability, security, and innovation, we continuously push the boundaries of what's possible in the payments industry. We are seeking an experienced Software Engineer to join our Payments Processing group. This group focuses on developing and maintaining world-class payment solutions, including PIN pad and card reader integration and processor/acquirer connectivity. The ideal candidate: The ideal candidate is a highly skilled software engineer with deep expertise in one or more of the following domains: Backend development (C#/.NET) Mobile SDK development for Android (Java/Kotlin) or iOS (Objective-C/Swift) You don’t need to be an expert in all these areas, but you should bring senior-level technical depth and design experience in at least one, combined with the ability and curiosity to work across the stack when needed. As a Senior Engineer, you will play a key role in designing, developing, and maintaining SDKs and backend components that enable secure, performant, and seamless payment transactions. You will be expected to take ownership of complex problems, influence architectural decisions, and contribute to improving our CI/CD, testing, and deployment processes. You’ll also provide mentorship, participate in design discussions, and help ensure that our systems and SDKs meet the highest standards of security, reliability, performance, and maintainability. Key Responsibilities: Design, develop, and maintain secure, scalable, high-quality SDKs and backend services used in payment device integrations. Lead architectural and design discussions across backend and mobile platforms. Write and review well-structured, maintainable, and efficient code. Collaborate closely with Product, QA, and Operations to ensure successful feat

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