Financial backend systems with KYC/AML, exchange integrations, blockchain nodes, and polyglot persistence.

Context

A financial platform needed onboarding, KYC/AML, exchange integration, and multiple data models for account and network workflows.

Problem

The exchange needed secure onboarding, fast data models, identity verification, and integrations with liquidity and blockchain infrastructure.

Constraints

Financial compliance, sensitive user documents, correctness, performance, and multiple persistence models.

Architecture

NestJS microservices with PostgreSQL, MongoDB, Neo4j, Redis, Elasticsearch, Binance integration, and blockchain nodes.

Implementation

Built KYC/AML verification, document validation, sanction screening, exchange integration, and network/accounting algorithms.

Impact

Enabled compliant onboarding and scalable backend features for financial workflows.

Responsibilities

• NestJS microservice implementation
• KYC/AML and document validation workflows
• Exchange integration and persistence across PostgreSQL, MongoDB, Neo4j, Redis, and Elasticsearch

Tradeoffs

• Used different stores for relational, document, graph, cache, and search needs instead of forcing one database model.
• Kept compliance-sensitive flows explicit and auditable rather than hiding them in generic handlers.

Risks Managed

• Sensitive document handling
• Correctness of financial/accounting flows
• Integration reliability with exchange and blockchain infrastructure

Results

• Compliant onboarding foundation
• Scalable persistence model
• Exchange and blockchain integration support