# Ledger

> Documentation for Ledger, version 1.x.
> Every entry links to the page's markdown source.

Repository: https://github.com/xraph/ledger
Site: https://www.xraph.com/docs/ledger

## Pages

- [Go Packages](https://www.xraph.com/docs/ledger/api-reference/go-packages.md): Complete reference for all Ledger Go packages, types, and interfaces.
- [HTTP API](https://www.xraph.com/docs/ledger/api-reference/http-api.md): REST API reference for all Ledger billing endpoints.
- [Architecture](https://www.xraph.com/docs/ledger/architecture.md): How Ledger's billing packages fit together.
- [Configuration](https://www.xraph.com/docs/ledger/concepts/configuration.md): Configuring Ledger for production deployment and development environments.
- [Entities](https://www.xraph.com/docs/ledger/concepts/entities.md): The core data types in Ledger — Plans, Subscriptions, Invoices, Usage Events, and more.
- [Error Handling](https://www.xraph.com/docs/ledger/concepts/errors.md): Sentinel errors returned by Ledger operations.
- [Identity (TypeID)](https://www.xraph.com/docs/ledger/concepts/identity.md): How Ledger uses prefix-qualified, globally unique identifiers for every billing entity.
- [Multi-Tenancy](https://www.xraph.com/docs/ledger/concepts/multi-tenancy.md): How Ledger isolates billing data across organizations and customers for secure multi-tenant SaaS.
- [Getting Started](https://www.xraph.com/docs/ledger/getting-started.md): Install Ledger and create your first billing plan in under five minutes.
- [Custom Plugin](https://www.xraph.com/docs/ledger/guides/custom-plugin.md): Write custom plugins to extend Ledger with lifecycle hooks.
- [Custom Store](https://www.xraph.com/docs/ledger/guides/custom-store.md): Implement the store.Store interface for a custom storage backend.
- [Forge Extension](https://www.xraph.com/docs/ledger/guides/forge-extension.md): Mount Ledger as a Forge application extension with automatic tenant isolation.
- [End-to-End Billing Example](https://www.xraph.com/docs/ledger/guides/full-example.md): Complete walkthrough of a billing pipeline from plan creation through payment collection.
- [Introduction](https://www.xraph.com/docs/ledger.md): Modern billing engine for SaaS applications in Go.
- [Memory Store](https://www.xraph.com/docs/ledger/stores/memory.md): In-memory store implementation for testing and development.
- [MongoDB Store](https://www.xraph.com/docs/ledger/stores/mongo.md): MongoDB store for document-oriented and horizontally-scalable Ledger deployments.
- [PostgreSQL Store](https://www.xraph.com/docs/ledger/stores/postgres.md): Production-ready PostgreSQL store using grove ORM with pgdriver.
- [SQLite Store](https://www.xraph.com/docs/ledger/stores/sqlite.md): Lightweight SQLite store for development, testing, and single-node Ledger deployments.
- [Billing Cycles](https://www.xraph.com/docs/ledger/subsystems/billing-cycles.md): How Ledger manages subscription billing cycles, period calculations, and automated billing runs.
- [Coupons](https://www.xraph.com/docs/ledger/subsystems/coupons.md): Percentage and fixed-amount discounts with redemption tracking and validity windows.
- [Customer Management](https://www.xraph.com/docs/ledger/subsystems/customers.md): Manage customer profiles, billing addresses, and payment methods.
- [Entitlement Checking](https://www.xraph.com/docs/ledger/subsystems/entitlements.md): Sub-millisecond access control with Redis caching for feature gates and usage limits.
- [Invoice Generation](https://www.xraph.com/docs/ledger/subsystems/invoicing.md): Automated billing calculations from usage, subscriptions, and pricing rules.
- [Usage Metering](https://www.xraph.com/docs/ledger/subsystems/metering.md): High-throughput event ingestion for tracking customer consumption in real-time.
- [Billing System Overview](https://www.xraph.com/docs/ledger/subsystems/overview.md): How Ledger models usage-based billing as a composition of plans, subscriptions, metering, and invoicing.
- [Payment Processing](https://www.xraph.com/docs/ledger/subsystems/payments.md): Stripe and Paddle integration for collecting payments, managing payment methods, and handling webhooks.
- [Plans & Pricing](https://www.xraph.com/docs/ledger/subsystems/plans.md): Define what customers can access — features, usage limits, and graduated pricing tiers.
- [Subscriptions](https://www.xraph.com/docs/ledger/subsystems/subscriptions.md): Track customer commitments, lifecycle states, and plan associations.