But let's save you the time of reading the full long specification just to find those little pieces of information you need.

Let's use the tools provided by **FastAPI** to handle security.

## How it looks { #how-it-looks }

Let's first just use the code and see how it works, and then we'll come back to understand what's happening.

## Create `main.py` { #create-main-py }

Copy the example in a file `main.py`:

    for prod and one for tests. However, unlike our other packages, as of this
    writing it has test supersource but no prod supersource.

    GWT happens to use the prod .gwt.xml, so it looks for no supersource for
    tests, either. This causes it to fail to find AtomicLongMapTest.

    Our workaround is to tell GWT that util.concurrent and all other packages

    private final List<Thread> hooks = new ArrayList<>();

    @Override
    synchronized void addShutdownHook(Thread hook) {
      hooks.add(hook);
    }

    synchronized void shutdown() throws InterruptedException {
      for (Thread hook : hooks) {
        hook.start();
      }
      for (Thread hook : hooks) {
        hook.join();
      }
    }
  }

  - 💾 [PostgreSQL](https://www.postgresql.org) als SQL-Datenbank.
- 🚀 [React](https://react.dev) für das Frontend.
  - 💃 Verwendung von TypeScript, Hooks, Vite und anderen Teilen eines modernen Frontend-Stacks.
  - 🎨 [Tailwind CSS](https://tailwindcss.com) und [shadcn/ui](https://ui.shadcn.com) für die Frontend-Komponenten.
  - 🤖 Ein automatisch generierter Frontend-Client.

We are going to start from where we left in the previous chapter and increment it.

## About JWT { #about-jwt }

JWT means "JSON Web Tokens".

It's a standard to codify a JSON object in a long dense string without spaces. It looks like this:

```
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c
```

      formattedType,
      windowSizeIncrement,
    )
  }

  internal fun formattedType(type: Int): String = if (type < FRAME_NAMES.size) FRAME_NAMES[type] else format("0x%02x", type)

  /**
   * Looks up valid string representing flags from the table. Invalid combinations are represented
   * in binary.
   */
  fun formatFlags(
    type: Int,
    flags: Int,
  ): String {
    if (flags == 0) return ""

 * </ol>
 * <p>By understanding and properly configuring repositories, developers can control where Maven looks for dependencies, manage access to proprietary artifacts, and optimize the build process to ensure consistency and reliability across projects.
 * </p>
 *
 *
 * @since 4.0.0
 * @see Repository
 * @see LocalRepository

 * </ol>
 * By understanding and properly configuring repositories, developers can control where Maven looks for dependencies, manage access to proprietary artifacts, and optimize the build process to ensure consistency and reliability across projects.
 *
 * @since 4.0.0
 * @see RemoteRepository
 * @see LocalRepository
 */

    - 🔍 [Pydantic](https://docs.pydantic.dev): FastAPI에 의해 사용되는, 데이터 검증과 설정관리.
    - 💾 [PostgreSQL](https://www.postgresql.org): SQL 데이터베이스.
- 🚀 [React](https://react.dev): 프론트엔드.
    - 💃 TypeScript, hooks, [Vite](https://vitejs.dev) 및 기타 현대적인 프론트엔드 스택을 사용.
    - 🎨 [Chakra UI](https://chakra-ui.com): 프론트엔드 컴포넌트.
    - 🤖 자동으로 생성된 프론트엔드 클라이언트.
    - 🧪 E2E 테스트를 위한 [Playwright](https://playwright.dev).
    - 🦇 다크 모드 지원.

    suite.addTest(
        MapTestSuiteBuilder.using(
                new TestTypeToInstanceMapGenerator() {
                  // Other tests will verify what real, warning-free usage looks like
                  // but here we have to do some serious fudging
                  @Override
                  @SuppressWarnings({"unchecked", "rawtypes"})