Senior Full Stack Engineer (Checkout)

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.

• 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

• React with TypeScript

• Viem and Wagmi (preferred)

Please note:

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

• Our default hiring model is a German employment contract for Germany-based candidates, or a B2B freelancer agreement for those based elsewhere.

• 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

• 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

• 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!

• 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

  • Try - don’t be afraid to fail

  • Learn - don’t make the same mistake twice

  • Adapt - grow with the experience

• Have fun together

  • Take the time to get to know and understand each other better

  • Don’t take yourself too seriously and keep it light-hearted

  • Fun should be coming from a place of love and respect

• Annual company offsites — we've explored Thailand, Vietnam, Morocco, and Greece together. Next stop for 2027: TBD!

• 30 days of PTO

• Flexible remote days

• Flexible working hours

• Equity participation from day 1

• Entitlement to work computer (choice of equipment)

• An annual 1,000€ personal development budget once you have worked 6+ months (pro-rated the first year)

• A one-time 1,000€ remote budget to use on coworking, office setup, etc.

If you join us as an independent contractor, you’re only entitled to the first five benefits of this list.

Setting yourself up for success starts with the application! Click here to discover valuable tips that will help you navigate our application process effectively.

LI.FI is an equal opportunity employer. We encourage individuals of all backgrounds to apply. Join us in our dedication to fostering a workplace that values and respects each team member's unique contributions.

Shortlisted candidates will undergo a comprehensive interview process, including a people operations interview, a take-home assignment, a meet-the-team & founder interview, and a reference check.

For more information, visit our page detailing our hiring process!