// If we hit the max load factor or we have too many overflow buckets,
	// and we're not already in the middle of growing, start growing.
	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
		hashGrow(t, h)
		goto again // Growing the table invalidates everything, so try again
	}

	if insertb == nil {

	// If we hit the max load factor or we have too many overflow buckets,
	// and we're not already in the middle of growing, start growing.
	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
		hashGrow(t, h)
		goto again // Growing the table invalidates everything, so try again
	}

	if insertb == nil {

	// If we hit the max load factor or we have too many overflow buckets,
	// and we're not already in the middle of growing, start growing.
	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
		hashGrow(t, h)
		goto again // Growing the table invalidates everything, so try again
	}

	if insertb == nil {

	// If we hit the max load factor or we have too many overflow buckets,
	// and we're not already in the middle of growing, start growing.
	if !h.growing() && (overLoadFactor(h.count+1, h.B) || tooManyOverflowBuckets(h.noverflow, h.B)) {
		hashGrow(t, h)
		goto again // Growing the table invalidates everything, so try again
	}

	if inserti == nil {

		clock_id int32
		tp       unsafe.Pointer
	}{_CLOCK_MONOTONIC, unsafe.Pointer(&ts)}
	if errno := libcCall(unsafe.Pointer(abi.FuncPCABI0(clock_gettime_trampoline)), unsafe.Pointer(&args)); errno < 0 {
		// Avoid growing the nosplit stack.
		systemstack(func() {
			println("runtime: errno", -errno)
			throw("clock_gettime failed")
		})
	}
	return ts.tv_sec*1e9 + int64(ts.tv_nsec)
}
func clock_gettime_trampoline()

	doublecap := newcap + newcap
	if newLen > doublecap {
		return newLen
	}

	const threshold = 256
	if oldCap < threshold {
		return doublecap
	}
	for {
		// Transition from growing 2x for small slices
		// to growing 1.25x for large slices. This formula
		// gives a smooth-ish transition between the two.
		newcap += (newcap + 3*threshold) >> 2

		// We need to check `newcap >= newLen` and whether `newcap` overflowed.

type spanSet struct {
	// A spanSet is a two-level data structure consisting of a
	// growable spine that points to fixed-sized blocks. The spine
	// can be accessed without locks, but adding a block or
	// growing it requires taking the spine lock.
	//
	// Because each mspan covers at least 8K of heap and takes at
	// most 8 bytes in the spanSet, the growth of the spine is
	// quite limited.
	//

         * than a handful of exceptions. But it seems prudent to set a cap on how many we'll cache.
         * This avoids out-of-control memory consumption, and it keeps the cache from growing so
         * large that doing the lookup is noticeably slower than redoing the work would be.
         *
         * Ideally we'd have a real eviction policy, but until we see a problem in practice, I hope

	//
	// Debuggers rely on us running on the same thread until we get to
	// dispatch the function they asked as to.
	//
	// We're going to transfer this to the new G we just created.
	lockOSThread()

	// Create a new goroutine to execute the call on. Run this on
	// the system stack to avoid growing our stack.
	systemstack(func() {
		// TODO(mknyszek): It would be nice to wrap these arguments in an allocated

<2> The `app` subproject
<3> The `app` source code
<4> The `app` build script
<5> The optional settings file
=====

== Step 2. Add another Subproject to the Build
Imagine that our project is growing and requires a custom library to function.

Let's create this imaginary `lib`.
First, create a `lib` folder:

[source,text]
----
mkdir lib
----

[source,text]
----
cd lib
----