fintech Solutions

Microservices Architecture for UK FinTech — FCA PS21/3 Built In

ClickMasters provides Microservices Architecture for UK FinTech businesses with FCA PS21/3, FCA Consumer Duty compliance from Sprint 1.

Updated June 20259 min readBy ClickMasters FinTech Team

Key Highlights

FinTechFCA PS21/3💷 £40,000–£200,000🔒 UK GDPR⚖️ IR35-Safe🇬🇧 UK

Compliance

FCA PS21/3
FCA Consumer Duty
PSD2
UK GDPR

+2 more standards

Pricing

FinTech Microservices Architecture£40,000–£200,000
Discovery£3,500–£8,000
Supportfrom £1,500/mo

Microservices Architecture for FinTech — UK Specifics

FCA PS21/3 Operational Resilience and Microservices

FCA Operational Resilience (PS21/3) requires firms to set Impact Tolerances for Important Business Services (IBS) and test that they can remain within those tolerances during severe but plausible disruption. Microservices architecture should map each IBS to specific services: payment processing → payment microservice SLAs, account access → identity and account services. Each microservice must have defined SLAs that support the IBS Impact Tolerance.

Circuit Breakers for FCA Operational Resilience Evidence

Microservices without circuit breakers can cause cascading failures — one slow service causes all dependent services to queue and fail. Circuit breaker pattern (Resilience4j for Java, opossum for Node.js): when downstream calls fail above threshold, the circuit opens and fast-fails requests, preventing cascade. FCA PS21/3 operational resilience testing: circuit breakers are direct evidence of fault isolation capability.

Distributed Transactions in FinTech Microservices

FinTech microservices frequently need distributed transactions: debit from account A AND credit to account B must both succeed or both fail. Options: Saga pattern (choreography or orchestration) — each service publishes events and compensating transactions roll back on failure. Two-phase commit (2PC) — avoid for microservices (too slow). ClickMasters uses Saga orchestration for FinTech payment flows — the orchestrator has the full audit trail required for FCA transaction reporting.

PCI-DSS Scope in FinTech Microservices

PCI-DSS scoping in microservices: only services that process, store, or transmit cardholder data are in-scope. Design principle: minimise scope by isolating cardholder data to a dedicated payment microservice using hosted payment fields (Stripe Elements/Adyen Drop-in). All other microservices communicate with the payment service via tokens — cardholder data never touches out-of-scope services.

Compliance

FCA PS21/3

FCA Consumer Duty

PSD2

UK GDPR

Cyber Essentials

PCI-DSS

Compliance & Regulations

Every solution we build for this industry is designed to meet the following regulatory and standards requirements.

FCA PS21/3

FCA Consumer Duty

PSD2

UK GDPR

Cyber Essentials

PCI-DSS

Investment Options

Flexible engagement models tailored to your fintech project requirements.

FinTech Microservices Architecture

£40,000–£200,000

Full engagement

  • Industry-specific approach
  • UK GDPR compliant
  • Dedicated technical lead
Most Popular
Discovery

£3,500–£8,000

Scoping

  • Industry-specific approach
  • UK GDPR compliant
  • Dedicated technical lead
Support

from £1,500/mo

Post-launch

  • Industry-specific approach
  • UK GDPR compliant
  • Dedicated technical lead

What Our Clients Say

Success stories from clients in fintech industry.

ClickMasters transformed our digital infrastructure. Their understanding of UK fintech regulations saved us months of compliance work.

S

Sarah Mitchell

CTO, FinTech Solutions Ltd

The team's expertise in NHS integrations and DTAC compliance was invaluable. They delivered on time and within budget.

D

Dr. James Cooper

Medical Director, HealthFirst UK

Their grasp of FCA requirements and insurance sector nuances helped us launch our platform 40% faster than expected.

M

Michael Brooks

CEO, InsureTech Pro

Frequently Asked Questions

Common questions about fintech software development.

How does FCA PS21/3 affect microservices architecture decisions?

FCA PS21/3 Impact Tolerances drive microservices design: each Important Business Service maps to specific microservices, and those services' SLAs must support the IBS tolerance. Design implications: redundant service deployment (minimum 2 instances per critical service), circuit breakers to prevent cascade, health check endpoints per service for monitoring, and chaos engineering tests to validate resilience claims.

How do we handle UK GDPR right to erasure in FinTech microservices?

Pattern: a dedicated PII Erasure Service orchestrates erasure across all data stores. Each microservice registers its personal data stores with the Erasure Service. On erasure request: Erasure Service broadcasts ErasureRequested event, each service implements its own erasure handler (delete/anonymise), and confirms completion. The Erasure Service maintains a compliance audit trail with per-service completion timestamps. FCA consideration: some FinTech transaction data must be retained for 5–7 years under Money Laundering Regulations — erasure applies to non-mandatory personal data fields only.

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