All open roles

Product Engineer

Engineering · Posted 8 months ago

Fun.xyz is hiring Product Engineers (mid, senior, staff) to design and scale the SDKs and product surfaces that power Checkout across web2 and web3 environments. The team owns user-facing flows and developer integrations, balancing performance, reliability, and UX for dApps and financial platforms integrating crypto payments. The role works directly with protocol and backend teams on technically complex, product-centric problems for onchain payments at scale.

Way of working
Hybrid
Location
Singapore
Pay range
SGD 120,000 to SGD 300,000
Level
Mid
Experience
3+ years
Type
Unknown
Visa sponsorship
Available for this role
The company
SERIES_A

Skills that matter here

JavaScriptTypeScriptReact

What you would be doing

  • Design, build, and maintain SDKs and UI components that embed Checkout into web2 and web3 apps.
  • Work across the stack, front-end focused and full-stack capable, to ship performant, reliable, and intuitive payment experiences.
  • Collaborate with protocol and backend teams to integrate complex payment, routing, and identity flows into simple developer and user APIs.
  • Own features end-to-end, including scoping, implementation, testing, and iteration based on product and customer feedback.
  • Contribute to code reviews, technical design discussions, and engineering standards to keep quality and velocity high as the team scales.

What they are looking for

  • JavaScript
  • Typescript
  • React

Worth knowing

  • Strong CS fundamentals
  • Blockchain EVM exposure
  • SDK developer tooling
  • High-scale fintech background
  • Shoveler mindset
  • Building from zero
  • Minimal scaffolding speed
  • Gritty hungry builders
  • Payments flow experience
  • Modern fintech ownership
  • Listed school background
  • Processes over $18 billion in annual transaction volume with 99.999% success rate while operating in stealth, supporting millions of users across 100+ countries
  • Powers deposits/withdrawals for major platforms including Polymarket, Lighter, and Aave
  • Exited stealth in May 2026 with $72M Series A; expanding to Asia-Pacific with new Singapore office and pursuing strategic acquisitions

The full description

**Fun.xyz** Product Engineer (Junior–Staff); SGD 120–300k across L1–L4 + equity; Singapore (open to relocation and visa sponsorship)

**About the Role** Fun.xyz is hiring Product Engineers (mid, senior, staff) to design and scale the SDKs and product surfaces that power Checkout across web2 and web3 environments. This team owns user-facing flows and developer integrations, balancing performance, reliability, and UX for dApps and financial platforms integrating crypto payments. You will work directly with protocol and backend teams to solve technically complex, product-centric problems for onchain payments at scale. This is currently a hybrid role but will turn into in-office, four days per week (Mon–Thu), with optional WFH Fridays.

**Responsibilities** - Design, build, and maintain SDKs and UI components that embed Checkout into web2 and web3 apps. - Work across the stack (front-end focused, full-stack-capable) to ship performant, reliable, and intuitive payment experiences. - Collaborate with protocol and backend teams to integrate complex payment, routing, and identity flows into simple developer and user APIs. - Own features end-to-end: scoping, implementation, testing, and iteration based on product and customer feedback. - Contribute to code reviews, technical design discussions, and engineering standards to keep quality and velocity high as the team scales.

**Required Skills** A. 3+ years of experience with JavaScript and TypeScript B. Professional experience with modern React-based front-ends. C. Strong understanding of full-stack development: client-side performance, state management, and integrating with backend APIs. D. Demonstrated ownership of user-facing products or features, ideally in payments, fintech, or high-traffic transactional products. E. Fintech / financial-services product experience require.

**Bonus Skills** - Solid computer science fundamentals and ability to reason about correctness, performance, and tradeoffs in product engineering decisions. - Experience with blockchain technologies or EVM-compatible networks; exposure to onchain payments or DeFi is a plus. - Prior work on SDKs, developer tools, or complex front-ends that integrate with third-party APIs. - Background in high-scale fintech or consumer apps (e.g., trading, wallets, neobanks). - Evidence of being a “shoveler”: low ego, willing to dive into unglamorous problems, and comfortable operating like an owner in a startup environment.

**Logistical Info** - **Location:** Singapore, open to relocation outside Singapore as well - **Compensation:** Fun.xyz targets roughly 75th percentile of market base comp with a broad band from ~120–300k (in SGD) across L1–L4, with equity scaled by level; Product Engineers are typically mid–staff within that range (exact band confirmed per candidate level).

**Ideal Background** - Candidates from these schools (no exceptions for now): https://www.hkengage.gov.hk/en/how-to-apply-for-a-visa/admission-scheme-matching-tool-institutions - Product engineers from top CS/STEM programs and strong engineering orgs who have built user-facing flows in payments, trading, or financial products. (From call.) - Front-end or full-stack engineers from modern fintechs, consumer crypto apps, or infra platforms outside the do‑not‑target list, with clear evidence of owning product surfaces.

**Green Flags** - Building something from zero vs. maintaining or optimizing existing systems - Candidates that can move fast with 'minimal scaffolding' (ideally from startups or fast teams where speed and ambiguity were the norm) - Gritty, hungry builders

**Red Flags** - Bootcamp-only backgrounds with no substantial professional track record in demanding product environments (Team tends to auto-reject these, with rare exceptions) - Pure bank backgrounds (0% pass rate; deprioritizing entirely); Java isn't a disqualifier, but seeing correlation between Java and bank/finance backgrounds and failing their screen - Candidates with CEX backgrounds that were on 'slow teams' vs faster startup-esque teams (identify which teams candidates were on; do not submit based on logo alone) - Senior candidates (10-20 YoE) from banks who hopped to CEX - Pure design/graphic/animation portfolios without evidence of deep React/TypeScript product engineering. - Candidates who explicitly resist in-office work or cannot reasonably be in NYC. - Candidates coming from Gemini are an instant no. - Large-tech-only backgrounds without fintech are rejected

**Interview Process** 1. Intro chat with hiring manager (Chloe) focused on culture, ownership, and product depth (no live coding). 2. Short take-home React/TypeScript exercise (expected to be quick; up to 5 days allowed). 3. Live React-heavy technical session with a Product Engineer via CoderPad. 4. Onsite for deeper technical and systems design interviews; potential founder chat depending on bandwidth.

Interested in this one?

There is no apply button here on purpose. Tell us about yourself, we book a short call, and if this role fits we walk you through the company and ask before anything is sent. Always free for you.

Tell us about you
Tell us about you