At a Glance
- Tasks: Lead the architecture and delivery of AI-driven payment systems with cutting-edge technology.
- Company: Global payments tech company focused on innovation and team empowerment.
- Benefits: Competitive salary, remote work, and opportunities for professional growth.
- Other info: Join a culture that prioritises outcomes, autonomy, and engineering excellence.
- Why this job: Tackle unique challenges at the intersection of AI and payments while shaping the future.
- Qualifications: 8-10 years in software engineering with expertise in TypeScript/Node.js or Python.
The predicted salary is between 80000 - 100000 £ per year.
Payments Technology | Remote | Permanent
At a Glance
- Role: Principal Engineer, AI Platform (MCP)
- Location: Remote
- Salary: Competitive
- Employment type: Permanent, full-time
- Stack: TypeScript / Node.js or Python, MCP SDKs, OAuth 2.0 / OIDC, Cloudflare Workers, Streamable HTTP
The Company
Our client is a global payments technology business building the next generation of capabilities for a merchant-first ecosystem. They operate at real scale, working with partners and merchants across multiple markets, and their engineering culture is built around small, empowered teams solving hard, real-world problems. The culture here is outcomes over outputs. Teams are trusted to work with autonomy, supported with the right tools, and given the space to think carefully and build well. If you are the kind of engineer who wants to master a domain rather than just ship tickets, this is the right environment.
The Role
This is one of the most technically interesting principal engineering roles we have brought to market this year. You will own the architecture and delivery of a suite of Model Context Protocol (MCP) servers that serve as the trusted, governed gateway between large language models and a production payment platform. As AI-driven interfaces become a primary way partners and internal teams interact with payment systems, these servers sit at the heart of that shift. You will define the transport and session model, implement OAuth-based authentication and authorisation, design the tooling and elicitation surfaces that agents depend on, and build the operational backbone that keeps everything safe and reliable at scale. This is a hands-on principal role. You will set technical direction, write production code, define patterns and libraries that other teams will build on, and raise the bar for engineering quality across a domain that is new, fast-moving, and security-sensitive.
What You'll Be Doing
- Own the architecture and delivery of MCP servers exposing platform data and capabilities to AI agents and developer tooling
- Design the transport and session model (Streamable HTTP), including stateful sessions for progress streaming, subscriptions, sampling, and user elicitation flows
- Implement robust authentication and authorisation using OAuth 2.0 / OIDC, JWT validation, and least-privilege per-request data scoping
- Design and operate the edge and gateway layer (Cloudflare Workers / Durable Objects) for token validation, JWKS caching, routing, and session state
- Define standards, patterns, and reusable libraries so other teams can build additional MCP servers quickly, consistently, and securely
- Embed security and compliance into every layer, treating these servers as a high-trust surface over sensitive payment data
- Drive observability, performance, and reliability: logging, tracing, rate limiting, timeouts, graceful degradation, and clean failure modes
- Build quality in across the software lifecycle using Behavioural Driven Development and CI/CD
- Mentor engineers, review designs and code, and evaluate emerging AI and agent technologies for applicability
- Translate partner, merchant, and internal developer needs into well-designed, high-quality solutions
What You'll Bring
Essential
- 8 to 10 years of software engineering experience, with a track record of owning systems end to end
- Deep server-side development expertise in TypeScript / Node.js or Python, given the maturity of the official MCP SDKs
- Strong, hands-on familiarity with the Model Context Protocol: defining tools, resources, and prompts; designing well-typed input/output schemas; and writing tool descriptions that drive reliable model behaviour
- Solid understanding of LLM tool-use and agentic patterns, including how models select and invoke tools, manage context, and handle multi-step interactions
- Hands-on experience with OAuth 2.0 / OIDC, JWT validation, token scoping, and identity provider integration
- Experience deploying and operating services at the edge or in serverless environments (Cloudflare Workers / Durable Objects, AWS Lambda, Cloud Run, or comparable)
- Strong understanding of secure HTTP API design, including streaming and SSE, and stateful vs. stateless service design
- Security-first mindset, ideally with exposure to regulated or payments environments (PCI DSS awareness a strong plus)
- Awareness of the safety considerations specific to AI agent tooling: prompt injection, over-broad permissions, and safe handling of model-driven actions
- Solid grounding in database design, caching, message-oriented middleware, and systems integration
- Comfortable operating with a high degree of ambiguity, able to set direction, experiment, and backtrack when needed
Nice to Have
- Direct experience building with agent frameworks or LLM application SDKs beyond MCP
- Background in payments or other regulated financial services environments
- BS or MS in Computer Science or a related field
Why Apply
- A genuinely novel technical problem at the intersection of payments infrastructure and AI agent systems
- Principal-level ownership with real architectural authority and scope to define how this domain is built
- A culture that values engineering craft, autonomous teams, and outcomes over process
- No needless bureaucracy: small teams, hard problems, space to do your best work
- Competitive compensation with the ability to grow with a business operating at serious scale
Interested? Apply directly or reach out to Ryan Quinn at Ocho for a confidential conversation.
Principal Engineer in Maidstone employer: Ocho Ocho
Our client is an exceptional employer, offering a dynamic remote work environment that prioritises engineering excellence and innovation. With a strong focus on employee autonomy and a culture that values outcomes over outputs, engineers are empowered to tackle complex challenges while enjoying competitive compensation and ample opportunities for professional growth. Joining this global payments technology business means being at the forefront of AI-driven solutions in a supportive and collaborative atmosphere, where your contributions directly impact the future of payment systems.
StudySmarter Expert Advice🤫
We think this is how you could land Principal Engineer in Maidstone
✨Tip Number 1
Network like a pro! Reach out to folks in your industry on LinkedIn or at meetups. A personal connection can often get you a foot in the door faster than any application.
✨Tip Number 2
Show off your skills! Create a portfolio or GitHub repo showcasing your projects, especially those relevant to AI and payments tech. This gives potential employers a taste of what you can do.
✨Tip Number 3
Prepare for interviews by practising common technical questions and scenarios related to the role. We recommend doing mock interviews with friends or using online platforms to boost your confidence.
✨Tip Number 4
Don’t forget to apply through our website! It’s the best way to ensure your application gets seen by the right people. Plus, we love seeing candidates who are proactive about their job search!
We think you need these skills to ace Principal Engineer in Maidstone
Some tips for your application 🫡
Tailor Your CV:Make sure your CV reflects the skills and experiences that align with the Principal Engineer role. Highlight your expertise in TypeScript, Node.js, or Python, and any relevant experience with OAuth 2.0 or AI technologies.
Craft a Compelling Cover Letter:Use your cover letter to tell us why you're passionate about this role and how your background makes you a perfect fit. Share specific examples of past projects that showcase your problem-solving skills and technical leadership.
Showcase Your Technical Skills:In your application, don’t shy away from detailing your hands-on experience with server-side development and any familiarity with the Model Context Protocol. We want to see how you’ve tackled complex engineering challenges in the past.
Apply Through Our Website:For the best chance of getting noticed, apply directly through our website. It’s the quickest way for us to receive your application and start the conversation about your future with us!
How to prepare for a job interview at Ocho Ocho
✨Know Your Tech Stack Inside Out
Make sure you’re well-versed in TypeScript, Node.js, or Python, as these are crucial for the role. Brush up on your knowledge of OAuth 2.0/OIDC and Cloudflare Workers, as being able to discuss these technologies confidently will show that you're ready to hit the ground running.
✨Demonstrate Your Problem-Solving Skills
Prepare to discuss specific challenges you've faced in previous roles, especially those related to server-side development and security. Use the STAR method (Situation, Task, Action, Result) to structure your answers and highlight how you’ve successfully navigated complex technical issues.
✨Showcase Your Architectural Vision
Be ready to talk about your experience with system architecture and design patterns. Think about how you would approach building the MCP servers and be prepared to share your ideas on transport models and session management. This will demonstrate your ability to think critically and strategically.
✨Emphasise Collaboration and Mentorship
Since this role involves mentoring other engineers, be prepared to discuss your experience in guiding teams and sharing knowledge. Highlight any past experiences where you’ve helped others grow or improved team dynamics, as this aligns with the company’s culture of empowered teams.
