Senior Backend Engineer – Payments/Fintech (AWS, Node.js)

Kieran Knight Consulting; England; Hybrid; GBP 70,000 - 100,000; Full time

Benefits offered by this job

Equity/Options

Mentorship from CTO

Growth opportunities

Job summary

Kieran Knight Consulting is recruiting a Software Engineer for a UK payments/fintech client. The role is hybrid with two days per month in the office and offers direct exposure to the CTO and a chance to shape the platform from the ground up.

You should have around 5 years of backend/full‑stack experience (Node.js/Next.js), with payments/fintech background and strong AWS serverless skills. You’ll design, build, and integrate services in a regulated environment, leading with ownership rather than

Qualifications

• Around 5 years' experience as a backend/full-stack engineer, with Node.js/Next.js exposure.
• Payments or fintech background essential with exposure to card payments/PSPs.
• Strong AWS experience (serverless, API Gateway, Postgres/Aurora).
• Ability to work independently with ownership; not a rigid ticket queue.
• Bonus: familiarity with PayFac, ISO, or payment gateway architecture.

Responsibilities

• Designing and building on AWS using serverless-first architecture.
• Working across the stack: APIs, data, integrations, and infrastructure.
• Integrating third-party services including payment processors and banking APIs.
• Building secure, PCI-aware systems for a regulated payments environment.
• Directing and reviewing third-party engineering teams' work rather than doing it solo.

Skills

5 years experience

Backend development

Node.js/Next.js

AWS serverless

Payments/Fintech

Independent ownership

Tools

AWS

Postgres/Aurora

Job description

Kieran Knight Consulting is recruiting a Software Engineer for a UK payments/fintech client. The role is hybrid with two days per month in the office and offers direct exposure to the CTO and a chance to shape the platform from the ground up.

You should have around 5 years of backend/full‑stack experience (Node.js/Next.js), with payments/fintech background and strong AWS serverless skills. You’ll design, build, and integrate services in a regulated environment, leading with ownership rather than