A quick run-down of the job

We're looking for a Senior Full-Stack Engineer (Checkout) to join our Embeddables squad and own the technical backbone of LI.FI's Checkout product. This is a backend-heavy full-stack role. You'll own full pipelines from UI components through to the backend services you build, focusing on provider integrations, routing intelligence, lifecycle state, and the partner-facing configuration that makes Checkout work end to end.

You'll join at an exciting moment as the product takes shape, with a substantial roadmap of provider integrations, recovery flows, and UX improvements ahead. You'll work across multiple teams including backend, partner portal, and over time composer, earn, and intent solver. Strong communication and the ability to navigate codebases independently matter as much as technical depth.

The role reports into the Embeddables/Checkout team and works closely with our Core backend team to ensure architectural alignment.

Our tech stack includes:

Backend:

• Node.js running TypeScript code in Docker containers

• MongoDB and Redis for our data

• ethers.js for communication with the blockchains

• Github, Kubernetes, AWS and CloudFlare for our GitOps CD chain

Frontend:

• React with TypeScript

• Viem and Wagmi (preferred)

Please note: This role is remote within the EMEA region. Your application will not be considered otherwise.

What you'll do

• Own Checkout-specific backend capabilities that power funding flows end to end, including provider integrations, quotes, sessions, statuses, deposit addresses, and recovery

• Design and build integration patterns for external providers (onramp, exchange, payment), normalising provider-specific behaviour into a consistent Checkout experience

• Define and maintain the backend contracts between Checkout UI, provider systems, and LI.FI's execution infrastructure, including robust state handling across long-running and failure-prone flows

• Drive cross-functional technical discovery when Checkout depends on Core backend, Partner Portal, or other adjacent teams, ensuring architectural alignment without drift

• Implement frontend work where useful, particularly when UI states and backend contracts need to be designed together

What makes a good candidate

• Strong backend engineering experience with expert proficiency in TypeScript/Node.js, plus full-stack ability to work across API contracts and UI states using React and TypeScript (viem and wagmi a plus)

• Proven experience integrating external APIs with provider-specific edge cases, with good instincts around async flows, failures, observability, and recovery

• Working-level Web3 knowledge: you understand transactions, block explorers, and how products like bridges and DEX aggregators fit together (smart contract development not required)

• Strong product judgement and the ability to navigate multiple teams and codebases without hand-holding, working across boundaries without creating architecture drift

• Excellent communication skills in English and comfort in a fast-paced, high-growth environment where priorities evolve quickly

Nice to have

• Experience integrating onramp, exchange, or payment providers

• Familiarity with payments, fintech, wallet, or exchange systems including webhooks, reconciliation, quote systems, KYC, geography, refunds, or recovery tooling

• Genuine enthusiasm for crypto and the Web3 ecosystem; Checkout uses many of LI.FI's own primitives and understanding how they fit together accelerates your impact

We encourage you to apply if you feel your experience and skills equip you for this job but are not listed here!

Company culture

• Embracing the differences

  • Embrace your own differences

  • Respect and welcome the unique qualities of others

  • See others’ differences as an opportunity to grow

• Own it, do it

  • Own tasks end-to-end

  • Hold yourself to a high bar for execution

  • Make bold decisions, and be accountable

  • Understand your limitations and seek for help

• Fail forward