You will see examples of this in the next chapters, about relational and NoSQL databases, security, etc.

## **FastAPI** compatibility

The simplicity of the dependency injection system makes **FastAPI** compatible with:

* all the relational databases
* NoSQL databases
* external packages
* external APIs
* authentication and authorization systems
* API usage monitoring systems

	copyPartsMetadata := make([]FileInfo, len(partsMetadata))
	for i := range latestDisks {
		if latestDisks[i] == nil {
			continue
		}
		copyPartsMetadata[i] = partsMetadata[i]
	}

	for i := range outDatedDisks {
		if outDatedDisks[i] == nil {
			continue
		}
		// Make sure to write the FileInfo information
		// that is expected to be in quorum.

		}, idx, *client.host)
	}
	return ng.Wait()
}

var errPeerNotReachable = errors.New("peer is not reachable")

// GetLocks - makes GetLocks RPC call on all peers.
func (sys *NotificationSys) GetLocks(ctx context.Context, r *http.Request) []*PeerLocks {
	locksResp := make([]*PeerLocks, len(sys.peerClients))
	g := errgroup.WithNErrs(len(sys.peerClients))
	for index, client := range sys.peerClients {
		index := index

I'll give you more concrete examples in the next chapters.

## Restarts

Similar to making sure your application is run on startup, you probably also want to make sure it is **restarted** after failures.

### We Make Mistakes

We, as humans, make **mistakes**, all the time. Software almost *always* has **bugs** hidden in different places. 🐛

				}
			}
			if err := w.Close(); err != nil {
				t.Fatal(err)
			}
		}
	}
	// 16k-1 records shouldn't make a zip64:
	t.Run("uint16max-1_NoZip64", func(t *testing.T) {
		t.Parallel()
		if generatesZip64(t, gen(0xfffe)) {
			t.Error("unexpected zip64")
		}
	})
	// 16k records should make a zip64:
	t.Run("uint16max_Zip64", func(t *testing.T) {
		t.Parallel()
		if !generatesZip64(t, gen(0xffff)) {

      assertSame(object, striped.getAt(i)); // idempotent
      observed.add(object);
    }
    assertTrue("All stripes observed", observed.size() == striped.size());

    // this uses #get(key), makes sure an already observed stripe is returned
    for (int i = 0; i < striped.size() * 100; i++) {
      assertTrue(observed.contains(striped.get(new Object())));
    }

    try {
      striped.getAt(-1);

      assertSame(object, striped.getAt(i)); // idempotent
      observed.add(object);
    }
    assertTrue("All stripes observed", observed.size() == striped.size());

    // this uses #get(key), makes sure an already observed stripe is returned
    for (int i = 0; i < striped.size() * 100; i++) {
      assertTrue(observed.contains(striped.get(new Object())));
    }

    try {
      striped.getAt(-1);

.PHONY: binaries-test
binaries-test:
	go test ${GOBUILDFLAGS} ./tests/binary/... -v --base-dir ${TARGET_OUT} --binaries="$(RELEASE_SIZE_TEST_BINARIES)"

# istioctl-all makes all of the non-static istioctl executables for each supported OS
.PHONY: istioctl-all
istioctl-all: ${TARGET_OUT}/release/istioctl-linux-amd64 ${TARGET_OUT}/release/istioctl-linux-armv7 ${TARGET_OUT}/release/istioctl-linux-arm64 \

		// If separator is not found or is last entry, ok.
		return idx == -1 || idx == len(ext)-len(separator)
	}
	return false
}

// isLatestDeletemarker returns whether the latest version is a delete marker.
// If metadata is NOT versioned false will always be returned.
// If v2 and UNABLE to load metadata true will be returned.
func (e *metaCacheEntry) isLatestDeletemarker() bool {
	if e.cached != nil {

> Modern versions of Python have support for **"asynchronous code"** using something called **"coroutines"**, with **`async` and `await`** syntax.

That should make more sense now. ✨

All that is what powers FastAPI (through Starlette) and what makes it have such an impressive performance.

## Very Technical Details

/// warning

You can probably skip this.