It is being chosen over previous alternatives for suiting many use cases better.

Many developers and teams already depend on **FastAPI** for their projects (including me and my team).

But still, there are many improvements and features to come.

**FastAPI** has a great future ahead.

 *
 * @author Mike Bostock
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible
/*
 * We provide and encourage use of ForwardingNavigableSet over this class, but we still provide this
 * one to preserve compatibility.
 */
@SuppressWarnings("JdkObsolete")
public abstract class ForwardingSortedSet<E extends @Nullable Object> extends ForwardingSet<E>
    implements SortedSet<E> {

		dstRec = &Record{}
	}
	dstRec.object = v
	return dstRec, nil
}

// Close - closes underlying reader.
func (r *Reader) Close() error {
	// Close the input.
	// Potentially racy if the stream decoder is still reading.
	if r.readCloser != nil {
		r.readCloser.Close()
	}
	if r.exitReader != nil {
		close(r.exitReader)
		r.readerWg.Wait()
		r.exitReader = nil
		r.input = nil
	}
	return nil
}

  * When annotating existing internal code, use `org.jetbrains.annotations.Contract`, e.g. `@Contract(null -> null; !null -> !null)`.
      When doing so, still annotate nullable parameters and the return type as `@Nullable`.
  * Do not use `@Contract` for public APIs.
  * For polynull public APIs, the solution has to be decided on a case-by-case basis.

   *       necessary that the hash be distributable across <i>inequivalence</i>. If {@code
   *       equivalence(x, y)} is false, {@code hash(x) == hash(y)} may still be true.
   *   <li>{@code hash(null)} is {@code 0}.
   * </ul>
   */
  public final int hash(@Nullable T t) {
    if (t == null) {
      return 0;
    }
    return doHash(t);
  }

  /**

	JMP	(AX)(AX*4)
	JCS	2(PC)
	JMP	R13

// LTYPEN spec4	{ outcode($1, &$2); }
	NOP
	NOP	AX
	NOP	foo+4(SB)

// LTYPES spec5	{ outcode($1, &$2); }
	SHLL	CX, R12
	SHLL	CX, foo+4(SB)
	// Old syntax, still accepted:
	SHLL	CX, R11:AX // SHLL CX, AX, R11

// LTYPEM spec6	{ outcode($1, &$2); }
	MOVL	AX, R11
	MOVL	$4, R11
//	MOVL	AX, 0(AX):DS // no longer works - did it ever?

// LTYPEI spec7	{ outcode($1, &$2); }

    }

    /**
     * Gets the identifier of the POM whose effective model could not be built. The general format of the identifier is
     * {@code <groupId>:<artifactId>:<version>} but some of these coordinates may still be unknown at the point the
     * exception is thrown so this information is merely meant to assist the user.
     *
     * @return The identifier of the POM or an empty string if not known, never {@code null}.
     */

   *
   * Note that transport-layer success (receiving a HTTP response code, headers and body) does not
   * necessarily indicate application-layer success: `response` may still indicate an unhappy HTTP
   * response code like 404 or 500.
   *
   * @throws IOException if the request could not be executed due to cancellation, a connectivity

    expectReturnsTrue(disjoint);
    expectContents();
  }

  // retainAll(null)

  /*
   * AbstractCollection fails the retainAll(null) test when the subject
   * collection is empty, but we'd still like to test retainAll(null) when we
   * can. We split the test into empty and non-empty cases. This allows us to
   * suppress only the former.
   */

  @CollectionFeature.Require(SUPPORTS_REMOVE)

By only using `BackgroundTasks` (and not `BackgroundTask`), it's then possible to use it as a *path operation function* parameter and have **FastAPI** handle the rest for you, just like when using the `Request` object directly.

It's still possible to use `BackgroundTask` alone in FastAPI, but you have to create the object in your code and return a Starlette `Response` including it.