Backend Engineer II/III (Node.js Payments & Platform)
The role
SuperLiving is a Series A consumer-AI wellness company, and our Node.js backend is where the money and the identity live - payments, subscriptions, autopay, login, entitlements, and the growth data that tells us whether any of it is working.
We're looking for a senior backend engineer who treats these systems as their own. Someone who can build a mandate flow and tell you why the renewal success rate dipped last Tuesday. This is a high-ownership IC role on the systems the whole business runs on.
What you'll own
Payments and subscriptions - the core of the job. You'll build and run the money layer end to end:
- Recurring autopay / mandates across Razorpay and PhonePe - setup, debit execution, subscription swaps, reactivation, plan changes
- One-time payments, cards and UPI, and in-app purchases on both iOS and Android (App Store / Play Store), reconciled back to a single entitlement
- Renewals - the debit that fires on time, the retry when it fails, the reactivation when a user comes back
- Payment recovery and reconciliation - the background workers that chase failed debits, reconcile our records against the gateway, and make sure we never lose money to a dropped webhook or a mismatched state
- Webhooks that cannot fail - signed, idempotent, replay-safe, because a missed one is a user who paid and didn't get access
The numbers behind the money, proactively. Writing the integration is half the job. You watch payment success rate per gateway, renewal rate, recovery rate, and store-vs-gateway mix, and you go find out why a number moved before someone asks. You treat a 2% SR drop as a bug, not a metric.
Login and identity - OTP login over SMS (MSG91) and WhatsApp, JWT/session handling, social login, and the mobile sign-in funnel itself, you own the login success ratio the same way you own payment SR, because a login that fails is a user who never reaches the paywall.
Backend features across the product - Beyond money and auth, you'll build the features the app depends on, such as courses, challenges/contests, games, notifications (FCM), entitlements, and home feed as a clean owner of your slice, behind our Go API gateway (auth handoff, routing, contracts the app and the Python AI backend both rely on).
Growth and analytics plumbing - The backend is where conversion truth is emitted. You'll own the server-side event pipeline into Meta (CAPI), Google Ads / Analytics, AppsFlyer and Mixpanel, making sure a purchase or trial fires the right event, attributed correctly, so Growth can actually trust the data.
Reliability and alerting. Idempotency on every money path, sane cron/worker jobs, and alerting you actually build, so a failing debit rail, a webhook backlog, or a login outage pages someone instead of surfacing in a support ticket a day later.
What we're looking for
- Strong Node.js / Express and PostgreSQL experience, building production backends that handle real money
- Deep payment-gateway experience - you've integrated recurring payments / autopay / mandates yourself (Razorpay, PhonePe, or comparable) and understand the lifecycle: mandate → debit → renewal → failure → recovery → refund
- Hands-on with mobile in-app purchases (App Store and/or Play Store) and reconciling them into a single source of truth
- Real auth/login experience - OTP (MSG91 or similar), WhatsApp/SMS providers, JWT/session security
- Numbers-driven and proactive - comfortable in the data, tracking successhasing a regression down rather than waiting for it to be reported
- Solid instincts for idempotency, webhooks, retries and reconciliation - you assume the network and the gateway will fail and design for it
- Familiarity with product/growth instrumentation (Mixpanel, Meta/Google ahy correct attribution matters
- AI-native - you build with tools like Claude Code as part of your normal workflow, keep shared context/knowledge in sync across repos, and get more done per day because of it
- High ownership. You treat the payments and auth systems as yours, not as
Bonus
- Experience with other gateways (Juspay, Cashfree, Stripe) or building a layer
- Redis, background-worker/queue design, and reconciliation at scale
- Fraud / failed-payment analytics, or dunning/win-back flows
- Comfort reading infra, latency and cost metrics (AWS, Postgres) and acting on them
What this role is not
- Not a CRUD-endpoint role - this is the money and identity core of the product
- Not "integrate the SDK and move on" - you own the lifecycle, the edge cases, and the numbers
- Not passive - nobody will hand you the regression, you're expected to find it
Why SuperLiving
- Own the payments and auth backbone of a fast-scaling Consumer AI company
- Direct, visible impact on revenue - every point of success rate will be yours
- Small, senior team, high autonomy, ship to real users every week
- Build with a modern, AI-native engineering stack from the ground up
This role is hosted on the company's careers site.