Learn Java Payment Systems
// Structured learning track for Learn Java Payment Systems.
This overview is designed to help you choose the right entry point quickly. Follow the full track from lesson one, continue from your last checkpoint, or jump straight into a phase that matches what you need right now.
Curriculum Map
Navigate by phase, then choose the lesson that matches your current depth.
Learn Java Payment Systems Part 001 Payment System Mental Model
22 minLearn Java Payment Systems Part 002 Payment Ecosystem Map
22 minLearn Java Payment Systems Part 003 Production Scope Boundary
25 minLearn Java Payment Systems Part 004 Payment Lifecycle Deep Dive
21 minLearn Java Payment Systems Part 005 Core Invariants
21 minLearn Java Payment Systems Part 006 Domain Language And Ubiquitous Model
19 minLearn Java Payment Systems Part 007 Money Correctness
15 minLearn Java Payment Systems Part 008 Payment State Machines
14 minLearn Java Payment Systems Part 009 Idempotency As A Financial Control
16 minLearn Java Payment Systems Part 010 Reference Architecture
16 minLearn Java Payment Systems Part 011 Api Surface Design
19 minLearn Java Payment Systems Part 012 Openapi Schema First Payment Apis
13 minLearn Java Payment Systems Part 013 Payment Orchestration Engine
16 minLearn Java Payment Systems Part 014 Provider Adapter Architecture
11 minLearn Java Payment Systems Part 015 Connector Contracts And Normalization
23 minLearn Java Payment Systems Part 016 Webhook Ingestion Engine
20 minLearn Java Payment Systems Part 017 Command Event And Ledger Boundaries
22 minLearn Java Payment Systems Part 018 Transactional Outbox Inbox Payment Flows
22 minLearn Java Payment Systems Part 019 Concurrency Control For Money Movement
22 minDouble-Entry Ledger Foundation
17 minBuilding the double-entry ledger foundation for a Java payment system, including accounts, journals, entries, posting rules, balance integrity, idempotency, reversals, corrections, and payment-specific accounting flows.
Learn Java Payment Systems Part 021 Ledger Schema Design
14 minLearn Java Payment Systems Part 022 Available Pending Settled Balances
11 minLearn Java Payment Systems Part 023 Fees Commission And Revenue Accounting
18 minLearn Java Payment Systems Part 024 Merchant Accounting Model
13 minLearn Java Payment Systems Part 025 Card Payment Architecture
17 minLearn Java Payment Systems Part 026 Card Data Security And Tokenization
18 minLearn Java Payment Systems Part 027 3ds And Strong Customer Authentication
16 minLearn Java Payment Systems Part 028 Iso8583 Processor Integration Model
14 minBank Transfer and Virtual Account Flows
16 minBank transfer and virtual account flows for enterprise-grade Java payment platforms: payment instructions, matching, expiry, reversal, bank statement ingestion, reconciliation, and ledger correctness.
Instant Payment Rails
17 minInstant payment rails for production Java payment systems: BI-FAST, FedNow, RTP-like rails, ISO 20022 message modeling, finality, confirmation, returns, alias resolution, liquidity, and real-time operations.