# Development - Contributing

First, you might want to see the basic ways to [help FastAPI and get help](help-fastapi.md){.internal-link target=_blank}.

## Developing

If you already cloned the <a href="https://github.com/fastapi/fastapi" class="external-link" target="_blank">fastapi repository</a> and you want to deep dive in the code, here are some guidelines to set up your environment.

### Virtual environment

   */
  public List<Integer> asList() {
    /*
     * Typically we cache this kind of thing, but much repeated use of this view is a performance
     * anti-pattern anyway. If we cache, then everyone pays a price in memory footprint even if
     * they never use this method.
     */
    return new AsList(this);
  }

  static class AsList extends AbstractList<Integer> implements RandomAccess, Serializable {

 *       safe for the next task to start.</i>
 * </ul>
 *
 * <p>This class is similar to {@link MoreExecutors#newSequentialExecutor}. This class is different
 * in a few ways:
 *
 * <ul>
 *   <li>Each task may be associated with a different executor.
 *   <li>Tasks may be of type {@code AsyncCallable}.

an older Go version, the Go toolchain amends its defaults
to match that older Go version as closely as possible.
For example, when a Go 1.21 toolchain compiles a program,
if the work module's `go.mod` or the workspace's `go.work`
says `go` `1.20`, then the program defaults to `panicnil=1`,
matching Go 1.20 instead of Go 1.21.

Because this method of setting GODEBUG defaults was introduced only in Go 1.21,

33E5          ; mapped                 ; 0036 65E5     # 1.1  IDEOGRAPHIC TELEGRAPH SYMBOL FOR DAY SIX
33E6          ; mapped                 ; 0037 65E5     # 1.1  IDEOGRAPHIC TELEGRAPH SYMBOL FOR DAY SEVEN
33E7          ; mapped                 ; 0038 65E5     # 1.1  IDEOGRAPHIC TELEGRAPH SYMBOL FOR DAY EIGHT
33E8          ; mapped                 ; 0039 65E5     # 1.1  IDEOGRAPHIC TELEGRAPH SYMBOL FOR DAY NINE

   */
  public List<Double> asList() {
    /*
     * Typically we cache this kind of thing, but much repeated use of this view is a performance
     * anti-pattern anyway. If we cache, then everyone pays a price in memory footprint even if
     * they never use this method.
     */
    return new AsList(this);
  }

  static class AsList extends AbstractList<Double> implements RandomAccess, Serializable {

 * ClassPath}</h2>
 *
 * <p>We recommend using <a href="https://github.com/classgraph/classgraph/wiki">ClassGraph</a>
 * instead of {@code ClassPath}. ClassGraph improves upon {@code ClassPath} in several ways,
 * including addressing many of its limitations. Limitations of {@code ClassPath} include:
 *
 * <ul>
 *   <li>It looks only for files and JARs in URLs available from {@link URLClassLoader} instances or

 * #from(ListenableFuture)} instead.
 *
 * <h3>Derived steps</h3>
 *
 * A {@code ClosingFuture} step can be derived from one or more input {@code ClosingFuture} steps in
 * ways similar to {@link FluentFuture}s:
 *
 * <ul>
 *   <li>by transforming the value from a successful input step,
 *   <li>by catching the exception from a failed input step, or

#### Dicas e orientações

* Verifique sempre os <a href="https://github.com/fastapi/fastapi/pulls" class="external-link" target="_blank">_pull requests_ existentes</a> para a sua linguagem e faça revisões das alterações e aprove elas.

/// tip

  // Required.
  optional string name = 2;
}

// Subject matches the originator of a request, as identified by the request authentication system. There are three
// ways of matching an originator; by user, group, or service account.
// +union
message Subject {
  // `kind` indicates which one of the other fields is non-empty.
  // Required
  // +unionDiscriminator