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+# Intrasys - Internal Transfers System
+
+![Rust](https://img.shields.io/badge/rust-%23000000.svg?logo=rust&logoColor=white)
+![PostgreSQL](https://img.shields.io/badge/PostgreSQL-316192?style=for-square&logo=postgresql&logoColor=white)
+![Tokio](https://img.shields.io/badge/Tokio-1.46-green?style=for-square)
+![Sqlx](https://img.shields.io/badge/Sqlx-0.8-green?style=for-square)
+![Axum](https://img.shields.io/badge/Axum-0.8-green?style=for-square)
+
+Intrasys is an internal financial transfers application built with Rust and Axum, providing HTTP endpoints for account management and transaction processing with PostgreSQL as the backing database.
+
+## Features
+
+- Account creation with initial balance
+- Account balance queries
+- Secure transaction processing between accounts
+- Atomic transaction handling with database integrity
+- Precise decimal arithmetic for financial amounts
+
+## Prerequisites
+
+- Rust (latest stable version)
+- Docker (for database provisioning)
+- PostgreSQL client (optional)
+
+## Quick Start
+
+### Using docker compose
+Just run
+
+```bash
+docker compose up
+```
+
+### Build locally
+
+#### Ensure you have rust installed
+Follow the steps described [here](https://www.rust-lang.org/tools/install) if you don't
+
+#### Provision PostgreSQL Database
+
+The easiest way is to run a PostgreSQL container with Docker:
+
+```bash
+docker run --name intrasys-pg -d -e POSTGRES_PASSWORD=password -p 127.0.0.1:5432:5432 postgres:alpine
+```
+
+#### Run the Application
+
+```bash
+cargo run
+```
+
+The application will be available at `http://localhost:8080`
+
+## API Endpoints
+
+### Account Management
+
+- **Create Account**  
+  `POST /accounts`
+  ```json
+  {
+    "account_id": 123,
+    "initial_balance": "100.23344"
+  }
+  ```
+
+- **Get Account Balance**  
+  `GET /accounts/{account_id}`  
+  Response:
+  ```json
+  {
+    "account_id": 123,
+    "balance": "100.23344"
+  }
+  ```
+
+### Transactions
+
+- **Process Transaction**  
+  `POST /transactions`
+  ```json
+  {
+    "source_account_id": 123,
+    "destination_account_id": 456,
+    "amount": "50.12345"
+  }
+  ```
+
+## Configuration
+The app can be configured using environmental variable that can also be provided through a `.dotenv` file.
+The following variables affect the application behavior:
+
+- `INTRASYS_LOG` changes the logging level, can be set to one of `trace`, `debug`, `info`, `warn`, `error`
+- `INTRASYS_HOST` is the address the HTTP server will bind to
+- `INTRASYS_PORT` is the port the HTTP server will listen to
+- any of the environmental variables mentioned [here](https://docs.rs/sqlx/latest/sqlx/postgres/struct.PgConnectOptions.html#method.options) affects the postgres database connection
+
+## Running tests
+
+Make sure you have an available postgres database and edit `DATABASE_URL` variable in the `.env` file accordingly. If you've used the docker command mentioned in the *Quickstart*
+section you don't need to change anything.
+
+Then run
+
+```bash
+cargo test
+```
+
+## Assumptions
+
+- All accounts use the same currency
+- No authentication or authorization is implemented
+- Decimal precision of 2 decimal places is sufficient for financial amounts, maximum allowed monetary amount is (10^18 -0.01) and the minimum is (-10^18 + 0.01)
+- Account IDs are positive integers
+- Account creation must NOT be idempotent since it also sets the account balance (creating an account that already exists should fail)
+- Transfer money to an account that does not exist should not create a new account, but fail with an error (to prevent users from accidentally locking their money forever)
+