> For the complete documentation index, see [llms.txt](https://entrytarget.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://entrytarget.gitbook.io/docs/readme.md).

# Introduction

Welcome to the official documentation for **EntryTarget** — a high-performance, double-entry financial ledger backend.

## What is EntryTarget?

EntryTarget is a financial core for companies that need reliable, auditable money movement. It implements double-entry bookkeeping behind a REST/JSON API, delivered as **one container image per customer**, running entirely on your own segregated AWS infrastructure (Fargate + RDS PostgreSQL). Your data never leaves your AWS account.

Billing is a **fixed monthly price**, independent of usage volume.

## Key Features

* **Double-entry bookkeeping** — every journal entry carries postings whose debits and credits always balance
* **Chart of accounts & balance limits** — accounts are classified by referencing a `DETAIL` record of the chart of accounts, which supplies their accounting type (`ASSET`, `LIABILITY`, `EQUITY`, `REVENUE`, `EXPENSE`) and category; each account carries two independent balance caps
* **High throughput** — tens of thousands of transactions per second on a single instance
* **Atomic transactions** — multi-entry, multi-currency transactions execute as a single unit
* **Authorizations** — authorization / capture / void flows for hold-style movements
* **Idempotency with replay** — retrying a write with the same key and identical request returns the original response
* **Append-only history** — postings are never mutated; reversals are real accounting transactions
* **Transaction metadata** — an optional JSON document of your own on selected transactions, for references to receipts and external ids
* **Observability** — Prometheus metrics with Grafana dashboards

## What EntryTarget Is Not

* **Not a customer registry.** Your application owns its own account/customer data and uses EntryTarget solely as the financial core — balances, transactions, postings.
* **Not a multi-tenant SaaS.** Each customer runs their own isolated instance and database, in their own AWS account.
* **Not a business-rules engine.** EntryTarget enforces accounting invariants (balanced entries, balance limits, asset matching). Business coherence — who may pay whom, how much, when — is your application's job.

## Design Principles

* **Integer amounts** — all monetary values are integers. You control decimal places (e.g., US$1.00 = 100).
* **Append-only history** — postings are never updated or deleted. Reversals (voids, compensations) write new postings.
* **A `201` means durably committed** — every accepted transaction is durable before the response is sent.
* **Fail fast** — invalid configuration stops the process at startup; there is no degraded mode.
* **Closed scope** — the system does exactly what it needs to do, nothing more.

## Getting Started

1. [Register on the Console and provision your instance](/docs/getting-started/provisioning.md)
2. [Set up API credentials](/docs/getting-started/credentials.md)
3. [Create accounts and execute your first transaction](/docs/getting-started/first-transaction.md)

## Need Help?

Access the vendor Console at `https://console.entrytarget.com/` for support and instance management.