How to Build a Bank Ledger in Golang with PostgreSQL using the Double-Entry Accounting Principle.

A comprehensive guide to building a bank ledger in Go and PostgreSQL using double-entry accounting principles. Covers the core schema design with database-enforced constraints, type-safe SQL generation with sqlc, serializable transaction isolation with automatic retry logic, row-level locking to prevent race conditions, and a reconciliation function to verify correctness. The guide walks through deposit, withdrawal, and transfer operations, explains why the settlement account goes negative, and demonstrates concurrency testing with goroutines. Also covers JWT authentication, amount normalization to avoid float precision issues, Docker deployment with migration retry logic, and HTTP server timeout configuration.