Senior Full Stack Engineer

About Switch Hub

Switch Hub is building the payment infrastructure that makes sending money across borders feel local.

We run a live consumer app for iOS and Android, a business platform for companies and fintechs, an internal operations platform, and the payment infrastructure underneath them.

We are a regulated payments company with real traction: Bank of Canada payment service provider approval, FINTRAC registration, and a Central Bank of Nigeria IMTO licence.

Real people and real businesses move real money through Switch Hub every day.

That changes what good engineering means.

A duplicate webhook is not just an annoying bug. It can result in money being credited twice. A race condition can affect a wallet balance. An incorrect retry can create a duplicate payout. A poorly designed permission can expose financial or personal information.

We are looking for a Senior Full Stack Engineer who understands that level of responsibility and wants to help us build systems that are secure, reliable and easy to operate.

The Role

You will work across our product and payments stack, building customer-facing features, internal operational tools and the APIs behind them.

This is a genuinely full stack role.

Some weeks you may be implementing an API that orchestrates a payment provider and safely handles asynchronous webhooks. Other weeks you may be building an operations workflow in React, improving a business onboarding journey, debugging a production transaction, strengthening our audit trail, or designing a safer way to process financial state changes.

You will work closely with engineering, product, QA, compliance and operations, and you will have significant ownership over the systems you build.

We are looking for someone who can go beyond completing Jira tickets.

You should be able to understand a problem, question the proposed solution, think through failure modes, design the implementation, build it, test it, document it, ship it safely and help operate it in production.

What You Will Do

• Design, build and maintain production features across our Node.js APIs and React/Next.js applications.
• Build secure REST APIs using TypeScript, PostgreSQL and Prisma.
• Develop customer, business and internal operations workflows with React and Next.js.
• Work on financial flows including wallet funding, transfers, payouts, FX conversion, fees, transaction limits and ledger-related operations.
• Integrate and maintain third-party payment and compliance providers.
• Build reliable webhook-driven workflows where events may be delayed, duplicated, retried or received out of order.
• Design financial operations to be idempotent and safe under retries, concurrency and partial provider failures.
• Work with PostgreSQL directly when investigating transactions, balances, ledger entries and production issues.
• Build and maintain strong validation, authentication, authorisation, rate limiting and audit logging around sensitive operations.
• Protect personal and financial data throughout the application lifecycle.
• Build internal tools that allow operations and compliance teams to safely investigate and manage customers and transactions.
• Write database migrations carefully and design changes that can be deployed and rolled back safely.
• Add appropriate unit, integration and end-to-end tests for the systems you build.
• Participate in code reviews and help maintain a high engineering standard across the team.
• Review pull requests with particular attention to security, data integrity, financial correctness and maintainability.
• Investigate production issues using logs, traces, database records and provider data rather than relying only on what the UI displays.
• Improve observability so we know when transactions, integrations or critical workflows are failing.
• Contribute to architecture decisions as the platform grows across additional currencies, countries and payment rails.
• Maintain clear technical documentation, runbooks and API documentation for systems you own.
• Work closely with QA to identify edge cases before they become production incidents.
• Collaborate with compliance and operations when engineering decisions affect KYC, KYB, AML, transaction monitoring or regulatory controls.
• Take ownership of your work from design through production.

Our Stack

You do not need to have used every technology below, but you should be very comfortable with the core technologies and able to learn the rest quickly.

• Backend: Node.js, TypeScript, Express and Fastify
• Frontend: React, Next.js, TypeScript
• Mobile: Flutter
• Database: PostgreSQL
• ORM: Prisma
• API: REST, OpenAPI and Postman
• CI/CD: GitHub and GitHub Actions
• Testing: automated API, integration and end-to-end testing
• Observability: structured logging, error monitoring, metrics and tracing
• Integrations: payment, banking, identity, compliance and messaging providers

Our payment infrastructure includes integrations across several rails and currencies, so experience working with external APIs and asynchronous systems is particularly valuable.

What We Are Looking For

Must Have

• Strong professional experience building production web applications as a software or full stack engineer.
• Strong TypeScript and JavaScript.
• Strong Node.js backend development experience.
• Strong React experience and a good understanding of modern frontend architecture.
• Very good PostgreSQL and relational data modelling skills.
• Experience building and consuming REST APIs.
• Experience designing authentication and authorisation systems securely.
• Experience working with asynchronous processes, queues, events or webhook-driven systems.
• Good understanding of database transactions, concurrency and data consistency.
• Strong Git and collaborative code review practices.
• Experience writing automated tests rather than relying entirely on manual testing.
• Ability to investigate production problems methodically using logs, database queries and application behaviour.
• A security-aware engineering mindset.
• Ability to work independently in a remote environment and communicate clearly when blocked.
• Strong written communication and enough discipline to document the systems you build.

You should also understand concepts such as:

• Idempotency.
• Race conditions.
• Database transactions.
• Retry behaviour.
• Eventual consistency.
• Duplicate and out-of-order events.
• API authentication and authorisation.
• Rate limiting.
• Input validation.
• Secrets management.
• Audit logging.
• Safe database migrations.

You do not necessarily need payments experience to apply, but if these concepts are unfamiliar, this probably will not be the right senior role.

Nice to Have

• Previous experience in fintech, payments, remittance, banking or financial services.
• Experience working with wallets, payment accounts or double-entry ledgers.
• Experience integrating payment processors, banking APIs or payment rails.
• Experience with KYC/KYB platforms such as Sumsub.
• Experience with multi-currency systems and foreign exchange.
• Experience handling provider webhooks in production.
• Experience with Prisma.
• Experience with Fastify or Express.
• Experience with Next.js.
• Experience with Flutter or an interest in contributing to mobile when required.
• Experience with queues or event-driven architectures.
• Familiarity with OWASP application security principles.
• Experience with security-sensitive or regulated systems.
• Experience with observability, distributed tracing and production incident response.
• Experience deploying applications using Railway, AWS, GCP or similar cloud platforms.
• Experience with GitHub Actions or similar CI/CD systems.

What Success Looks Like

Within your first few months, we would expect you to:

• Understand the architecture and responsibilities of our consumer, business and internal operations systems.
• Safely take ownership of meaningful production features.
• Understand how money moves through Switch Hub and how our major providers interact with our systems.
• Be comfortable investigating a transaction from the user interface through the API, database, provider and webhook lifecycle.
• Improve the quality and maintainability of areas you work in rather than simply adding more code.
• Identify reliability or security risks before they become incidents.
• Contribute thoughtful architectural recommendations as the platform scales.
• Become someone the team trusts with sensitive financial flows.

The Kind of Engineer We Want

We care about judgement as much as coding speed.

A senior engineer here should be comfortable saying:

"I don't know yet, let me verify."

We would rather investigate something properly than make a confident guess about a financial transaction.

We also value engineers who leave systems better than they found them: clearer code, better tests, stronger monitoring, useful documentation and fewer surprises for the next person.

Why Join Switch Hub

• Real ownership. You will work directly on systems that move money and have meaningful influence over how they evolve.
• Real product. Customers and businesses already use Switch Hub to move real money.
• Interesting engineering problems. Payments involves distributed systems, asynchronous providers, financial ledgers, security, compliance and some genuinely difficult edge cases.
• Direct impact. You will work closely with the founders and core team without layers of bureaucracy between an idea and its implementation.
• Modern stack. TypeScript, Node.js, React, PostgreSQL and modern cloud infrastructure.
• Room to grow. As the engineering organisation grows, there will be opportunities to take greater technical and architectural leadership.
• Remote-first. Work remotely with sensible overlap with the rest of the team.

How to Apply

Alongside your CV, tell us about one production system or feature you have personally built that you consider technically difficult. What could go wrong, and how did you design around those failure modes?.

We are particularly interested in something involving payments, financial data, concurrency, third-party APIs, asynchronous processing, security, or another system where getting the details wrong had real consequences.

Tell us:

• What the problem was.
• What you personally owned.
• How you designed the solution.
• What could go wrong.
• How you protected against those failure modes.
• What you would do differently if you built it again.

We care much more about the depth of your answer than the technology names on your CV.

Switch Hub Consulting Inc. is an equal opportunity employer. We welcome applicants from all backgrounds.