A payments, wallets, lending, and wealthtech engineering practice. PCI-DSS-aware architecture, SCA/PSD2-aware payment flows, KYC-first onboarding, and subscription billing that reconciles to the penny — shipped from NY + Delhi on a six-week cadence.
Fintech software fails in the places generic web work never visits: the payment webhook that fires twice, the ledger that drifts a cent a day, the KYC step that drops forty percent of activated users. Eight build shapes cover most of what fintech founders bring us — each one an engineering discipline with its own failure modes, not a template with a new logo. Every engagement runs on the same six-week cadence we use for our B2B SaaS growth practice, with a written scope inside 48 hours of the first call.
iOS and Android apps for payments, savings, and investing. Biometric auth, real-time balances, offline-safe state, store-compliant release trains — built by engineers who have shipped money-movement UIs, not just CRUD screens.
Scope a fintech mobile build →Stripe and Razorpay integrations that survive the edge cases: SCA challenges, partial captures, refund races, duplicate webhooks. Idempotent handlers and daily reconciliation jobs come standard.
Wire payments that settle cleanly →Stored-value wallets with top-ups, P2P transfers, and spend controls. The ledger is the product: we build it double-entry, append-only, auditable, and reconciled daily against the processor.
Build the wallet on a real ledger →Origination flows, credit-decision hooks, document collection, repayment schedules, and a servicing dashboard — scoped to a lendable MVP inside one or two six-week cycles, not a year-long platform bet.
Launch a lending MVP faster →Real-time positions, P&L, watchlists, and charting that stays legible at density. Websocket data layers, virtualized tables, and a dark-mode-first visual system traders can live in for hours.
Make dense data legible →Metered, tiered, and entity-aware billing on Stripe Billing or Razorpay Subscriptions. Dunning, proration, invoicing, and revenue reporting your finance team signs off on without a spreadsheet sidecar.
Put billing on autopilot →Identity verification moved early in activation, scope-aware data collection, resumable flows, full audit trails. In our Edinburgh archetype pattern, a KYC-first rebuild lifted free-to-paid conversion from 9% to 22%.
Fix the onboarding drop-off →Multi-tenant fintech SaaS from zero: auth, billing, roles, observability, and the one workflow that differentiates you. We build the core and buy the commodity layers, so budget lands on the product.
Ship the SaaS core in weeks →An honest note first: certifications and attestations are statuses your company earns from an auditor — no development partner can hand them to you, and anyone claiming otherwise is selling theatre. What an engineering partner does control is whether the architecture makes your eventual audit cheap or expensive. We build for cheap: minimal card-data scope, encryption everywhere, audit trails from day one.
Card data never touches your servers. Tokenized fields, hosted checkout elements, and scope kept to the smallest PCI SSC self-assessment footprint your product allows.
3DS2 challenge handling, exemption logic, and retry paths designed against Stripe's SCA documentation so European card flows convert instead of erroring out.
Data minimization, regional residency options, deletion workflows, and consent records aligned with EU data-protection law rather than bolted on at audit time.
Audit logs, role-based access control, change management, and incident runbooks structured so a Type II readiness project is a checklist, not a rebuild.
Encryption at rest and in transit as a default, key management on the cloud provider's KMS, and secrets that never land in a repository or a log line.
Deep, documented integrations against Stripe, Razorpay, and Plaid — billing, payouts, bank linking, and transaction data on primary docs, not Stack Overflow folklore.
Four failure patterns show up in almost every fintech codebase we inherit. Each has a structural fix — not a patch — and each fix is cheaper the earlier it lands.
Verification bolted onto the end of onboarding drops users who already did the work. We move KYC early, make every step resumable, and collect only what the current scope requires. In the Edinburgh archetype, this rebuild halved activation drop-off and lifted free-to-paid from 9% to 22%.
Duplicate webhooks, SCA challenges abandoned mid-flow, refunds racing captures. We build idempotent webhook handlers, explicit payment state machines, and nightly reconciliation jobs that diff your ledger against processor reports — so a mismatch is a Slack alert, not a quarter-end surprise.
A mutable balance field is a bug factory. We model money as an append-only double-entry ledger: every movement has two sides, a reference, and a timestamp. Balances are derived, corrections are new entries, and the audit trail writes itself.
Teams that defer audit logs, RBAC, and encryption pay for them during diligence — when every engineer is needed elsewhere. We ship those as day-one architecture, so the readiness project runs alongside feature work instead of replacing it.
Fintech platforms are SaaS-shaped, so the honest ranges follow revenue stage. An MVP that takes a paying customer runs $30,000 to $80,000 over 10-16 weeks. A post-PMF platform with multi-tenancy and observability runs $80,000 to $200,000 over 16-26 weeks. Scale-stage — SSO, advanced billing, RBAC, audit logs — runs $200,000 to $500,000 over 24-40 weeks, and enterprise builds with multi-region deployment cross $500,000 to $1M+. SOC 2 Type II readiness, when you need it, adds $40,000-$120,000 of engineering plus $15,000-$40,000/year for the audit itself. The full stage-by-stage math, including the build-vs-buy table that saves $150K+ on most scale builds, lives in our SaaS development cost guide; if the product is app-first, the mobile app development cost guide covers the native and cross-platform ranges.
| stage | timeline | market range |
|---|---|---|
| MVP / pre-PMF | 10-16 weeks | $30K-$80K |
| Post-PMF | 16-26 weeks | $80K-$200K |
| Scale | 24-40 weeks | $200K-$500K |
| Enterprise | 32-52 weeks | $500K-$1M+ |
Scope moves price, not the conversation. Every quote arrives in writing within 48 hours of the intro call, itemized by build shape.
£60K to £380K MRR in 18 months.
Net dollar retention across the existing base.
Up from 9% after the KYC-first onboarding rebuild.
M12 customer-logo retention.
The pattern: a wealthtech SaaS at £60K MRR with self-serve activation but a stitched-together stack, FCA-registration scope its onboarding didn't honour cleanly, and a pricing page that fought the buyer's decision tree. Fourteen weeks, five workstreams — Next.js marketing site with regulator-credibility surfaces, KYC moved early into activation, pricing rebuilt around entity size and transaction volume, Stripe metered billing with dunning, and one cohort-revenue dashboard. ARPA moved from £790 to £1,420 across twelve months. Read the full Edinburgh fintech archetype, or see the same discipline applied to embedded finance in the Leeds retail-fintech archetype.
The cadence is the contract. Every build runs in six-week cycles with a demo every Friday, so you watch the product grow weekly instead of hoping at the end of a quarter.
A 30-minute call on your product, compliance surface, and stage. Written scope — build shapes, timeline, fixed fee — lands inside 48 hours of that first call.
Weeks one to two: flows, the ledger and data model, the compliance-aware surface map, and a clickable prototype of the money-movement screens before a line of production code.
Weeks two to five: senior engineers on a staging environment you can click from day three. Weekly Friday demos, payment sandboxes wired early, reconciliation jobs tested against seeded edge cases.
Week six: production cutover or app-store submission, monitoring and alerting live, incident runbooks handed over, and a go-live checklist your team co-signs.
The next six-week cycle is scoped from live data — activation cohorts, payment failure rates, ledger telemetry — not from a backlog written before users existed.
Fintech rewards proven primitives. We reach for typed languages, relational databases, and payment processors with real documentation — and spend the novelty budget on your product, not the plumbing.
115 people across two HQs and three satellites. No fake local offices, no bait-and-switch juniors — the engineers on the call are the engineers on the build.
US mornings overlap Delhi evenings, so blockers raised at your standup are often resolved before your next one. A near-continuous build day without the handoff tax.
The cadence is public and non-negotiable. You see working software weekly; a slipping build has nowhere to hide by week two.
Our cost guides print the real ranges before you ever book a call, and every scope arrives itemized in writing within 48 hours. Clutch 4.9, Upwork Top Rated Plus, D-U-N-S 650878346.
Our ERP and client portals run our own 115-person business daily — billing, roles, audit trails included. We carry a pager for software we built; that instinct ships with your build.
One build shape — an MVP, a payment integration, a KYC rebuild — scoped, priced, and shipped on the six-week cadence. Best when the outcome is nameable.
A standing senior pod running successive six-week cycles — features, compliance readiness, and optimization scoped from live product data each cycle.
Senior fintech engineers embedded in your standup, your repo, your review process. You direct; we ship at your bar or above it.
Not sure which shape? Start from the stage math in the SaaS development cost guide — the ranges there map one-to-one onto these engagement shapes.
The stage-gated plan we use to take a fintech SaaS from written scope to first paying customer without over-building.
The activation benchmarks that tell you whether a KYC-first flow is converting users or quietly bleeding them.
The decision tree for wallet and trading apps, where biometric auth and render performance decide the answer.
Fintech platforms follow SaaS cost stages. An MVP that takes a paying customer runs $30,000 to $80,000 over 10-16 weeks; a post-PMF platform with multi-tenancy runs $80,000 to $200,000; scale-stage with SSO, RBAC, and audit logs runs $200,000 to $500,000; and enterprise multi-region builds cross $500,000 to $1M+. App-first products add the native or cross-platform ranges from our mobile app cost guide. Every engagement starts with a 30-minute call and a written, itemized scope inside 48 hours.
A payment integration or KYC rebuild fits inside one six-week cycle. A fintech MVP — auth, billing, one core money workflow, admin panel — runs 10-16 weeks, usually two cycles. Post-PMF and scale-stage platforms run 16-40 weeks depending on tenancy model and compliance surface. The constant across all of them: a demo every Friday and a staging environment you can click from the first week of build.
Certification and attestation are statuses your company earns from a qualified auditor — no development agency can transfer them, and we won't pretend otherwise. What we deliver is PCI-DSS-aware and SOC 2-aware architecture: card data tokenized so it never touches your servers, scope kept to the smallest self-assessment footprint, audit logs and RBAC and encryption at rest and in transit from day one. Teams that build this way find the eventual audit is paperwork, not a rebuild.
TypeScript end to end. Next.js on the web, React Native or Flutter on mobile, Node.js services over PostgreSQL — often via Supabase at MVP stage — with Stripe or Razorpay for payments, Plaid for bank connections, and Onfido for identity verification. Infrastructure on AWS or Vercel with managed key management. Fintech rewards boring, well-documented primitives; we spend the novelty budget on your product's differentiating workflow, not on exotic plumbing.
Yes — and for fintech we insist on a defined handover either way. Launch includes monitoring, alerting, and incident runbooks. Most teams continue on a product retainer: successive six-week cycles scoped from live data such as activation cohorts, payment failure rates, and reconciliation telemetry. Teams taking it in-house get documented architecture, seeded test suites for the payment edge cases, and a transition window where our engineers pair with yours.
Both, with different disciplines. For startups the danger is over-building: we scope to the smallest lendable, payable, or billable MVP and buy commodity layers like auth and billing instead of building them. For enterprises the danger is under-architecting: tenancy, SSO, audit trails, and data residency have to be structural. Since 2017 we have shipped for 2,000+ brands across 55+ countries, and the first job on every fintech call is telling you which stage you are actually at.
This is one of our most-requested fintech rebuilds. The usual failure is verification bolted onto the end of onboarding, where it drops users who already invested effort. We move KYC early, split it into resumable steps, collect only what the current product scope requires, and wire every decision into an audit trail. In the Edinburgh fintech archetype, this pattern halved activation drop-off and lifted free-to-paid conversion from 9% to 22% — onboarding is a revenue lever, not a compliance checkbox.
Geography decides most of it. Stripe leads for US, UK, and EU flows — strongest billing primitives, mature SCA handling, the deepest documentation in payments. Razorpay leads for India: UPI, netbanking, local cards, and settlement flows built for Indian rails. Products straddling both markets get a processor-abstraction layer so a second provider is a configuration, not a rewrite. Either way the integration ships with idempotent webhooks, explicit payment state machines, and nightly reconciliation.
A 30-minute call on your product, your compliance surface, and your stage. You leave knowing which build shape fits and what it costs; the written scope follows within 48 hours.
Senior Full Stack Developer · Lucknow · 8 posts on the site
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