diff --git a/cmd/mkuimage/main.go b/cmd/mkuimage/main.go
index cdc7f07..7bfed17 100644
--- a/cmd/mkuimage/main.go
+++ b/cmd/mkuimage/main.go
@@ -12,14 +12,11 @@ import (
 	"log"
 	"log/slog"
 	"os"
-	"runtime"
-	"strings"
 
 	"github.com/dustin/go-humanize"
 	"github.com/u-root/gobusybox/src/pkg/golang"
 	"github.com/u-root/mkuimage/uimage"
-	"github.com/u-root/mkuimage/uimage/builder"
-	"github.com/u-root/mkuimage/uimage/uflags"
+	"github.com/u-root/mkuimage/uimage/mkuimage"
 	"github.com/u-root/uio/llog"
 )
 
@@ -68,8 +65,8 @@ func main() {
 	}
 
 	env := golang.Default(golang.DisableCGO())
-	f := &uflags.Flags{
-		Commands: uflags.CommandFlags{
+	f := &mkuimage.Flags{
+		Commands: mkuimage.CommandFlags{
 			Builder:   "bb",
 			BuildOpts: &golang.BuildOpts{},
 		},
@@ -84,15 +81,14 @@ func main() {
 	l.RegisterVerboseFlag(flag.CommandLine, "v", slog.LevelDebug)
 	flag.Parse()
 
-	l.Infof("Build environment: %s", env)
-	if env.GOOS != "linux" {
-		l.Warnf("GOOS is not linux. Did you mean to set GOOS=linux?")
+	m := []uimage.Modifier{
+		uimage.WithReplaceEnv(env),
+		uimage.WithBaseArchive(uimage.DefaultRamfs()),
+		uimage.WithCPIOOutput(defaultFile(env)),
 	}
-
-	// Main is in a separate functions so defers run on return.
-	if err := Main(l, env, f); err != nil {
-		l.Errorf("Build error: %v", err)
-		return
+	if err := mkuimage.CreateUimage(l, m, f, flag.Args()); err != nil {
+		l.Errorf("mkuimage error: %v", err)
+		os.Exit(1)
 	}
 
 	if stat, err := os.Stat(f.OutputFile); err == nil && f.ArchiveFormat == "cpio" {
@@ -100,79 +96,9 @@ func main() {
 	}
 }
 
-var recommendedVersions = []string{
-	"go1.20",
-	"go1.21",
-	"go1.22",
-}
-
-func isRecommendedVersion(v string) bool {
-	for _, r := range recommendedVersions {
-		if strings.HasPrefix(v, r) {
-			return true
-		}
-	}
-	return false
-}
-
 func defaultFile(env *golang.Environ) string {
 	if len(env.GOOS) == 0 || len(env.GOARCH) == 0 {
 		return "/tmp/initramfs.cpio"
 	}
 	return fmt.Sprintf("/tmp/initramfs.%s_%s.cpio", env.GOOS, env.GOARCH)
 }
-
-// Main is a separate function so defers are run on return, which they wouldn't
-// on exit.
-func Main(l *llog.Logger, env *golang.Environ, f *uflags.Flags) error {
-	v, err := env.Version()
-	if err != nil {
-		l.Infof("Could not get environment's Go version, using runtime's version: %v", err)
-		v = runtime.Version()
-	}
-	if !isRecommendedVersion(v) {
-		l.Warnf(`You are not using one of the recommended Go versions (have = %s, recommended = %v).
-			Some packages may not compile.
-			Go to https://golang.org/doc/install to find out how to install a newer version of Go,
-			or use https://godoc.org/golang.org/dl/%s to install an additional version of Go.`,
-			v, recommendedVersions, recommendedVersions[0])
-	}
-
-	keepTempDir := f.KeepTempDir
-	if f.TempDir == "" {
-		var err error
-		f.TempDir, err = os.MkdirTemp("", "u-root")
-		if err != nil {
-			return err
-		}
-		defer func() {
-			if keepTempDir {
-				l.Infof("Keeping temp dir %s", f.TempDir)
-			} else {
-				os.RemoveAll(f.TempDir)
-			}
-		}()
-	} else if _, err := os.Stat(f.TempDir); os.IsNotExist(err) {
-		if err := os.MkdirAll(f.TempDir, 0o755); err != nil {
-			return fmt.Errorf("temporary directory %q did not exist; tried to mkdir but failed: %v", f.TempDir, err)
-		}
-	}
-
-	// Set defaults.
-	m := []uimage.Modifier{
-		uimage.WithReplaceEnv(env),
-		uimage.WithBaseArchive(uimage.DefaultRamfs()),
-		uimage.WithCPIOOutput(defaultFile(env)),
-	}
-	more, err := f.Modifiers(flag.Args()...)
-	if err != nil {
-		return err
-	}
-
-	err = uimage.Create(l, append(m, more...)...)
-	if errors.Is(err, builder.ErrBusyboxFailed) {
-		l.Errorf("Preserving temp dir due to busybox build error")
-		keepTempDir = true
-	}
-	return err
-}
diff --git a/cmd/mkuimage/main_test.go b/cmd/mkuimage/main_test.go
index efd5b65..f53a47d 100644
--- a/cmd/mkuimage/main_test.go
+++ b/cmd/mkuimage/main_test.go
@@ -13,7 +13,9 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"regexp"
 	"strings"
+	"syscall"
 	"testing"
 
 	"github.com/u-root/gobusybox/src/pkg/golang"
@@ -22,9 +24,29 @@ import (
 	"golang.org/x/sync/errgroup"
 )
 
-var twocmds = []string{
-	"github.com/u-root/u-root/cmds/core/ls",
-	"github.com/u-root/u-root/cmds/core/init",
+func hasTempDir(t *testing.T, output string) {
+	t.Helper()
+	tempDir := regexp.MustCompile(`Keeping temp dir (.+)`).FindStringSubmatch(output)
+	if tempDir == nil {
+		t.Errorf("Keeping temp dir not found in output")
+		return
+	}
+	if fi, err := os.Stat(tempDir[1]); err != nil {
+		t.Error(err)
+	} else if !fi.IsDir() {
+		t.Errorf("Stat(%s) = %v, want directory", tempDir[1], fi)
+	}
+}
+
+func dirExists(name string) func(t *testing.T, output string) {
+	return func(t *testing.T, output string) {
+		t.Helper()
+		if fi, err := os.Stat(name); err != nil {
+			t.Error(err)
+		} else if !fi.IsDir() {
+			t.Errorf("Stat(%s) = %v, want directory", name, fi)
+		}
+	}
 }
 
 func TestUrootCmdline(t *testing.T) {
@@ -60,13 +82,15 @@ func TestUrootCmdline(t *testing.T) {
 	if err = os.WriteFile(filepath.Join(sampledir, "bar"), nil, 0o644); err != nil {
 		t.Fatal(err)
 	}
+	tempDir := filepath.Join(t.TempDir(), "tempdir")
 
 	type testCase struct {
 		name       string
 		env        []string
 		args       []string
-		err        error
+		exitCode   int
 		validators []itest.ArchiveValidator
+		wantOutput func(*testing.T, string)
 	}
 
 	noCmdTests := []testCase{
@@ -74,7 +98,6 @@ func TestUrootCmdline(t *testing.T) {
 			name: "include one extra file",
 			args: []string{"-nocmd", "-files=/bin/bash"},
 			env:  []string{"GO111MODULE=off"},
-			err:  nil,
 			validators: []itest.ArchiveValidator{
 				itest.HasFile{Path: "bin/bash"},
 			},
@@ -83,7 +106,6 @@ func TestUrootCmdline(t *testing.T) {
 			name: "fix usage of an absolute path",
 			args: []string{"-nocmd", fmt.Sprintf("-files=%s:/bin", sampledir)},
 			env:  []string{"GO111MODULE=off"},
-			err:  nil,
 			validators: []itest.ArchiveValidator{
 				itest.HasFile{Path: "/bin/foo"},
 				itest.HasFile{Path: "/bin/bar"},
@@ -122,7 +144,6 @@ func TestUrootCmdline(t *testing.T) {
 		{
 			name: "uinitcmd",
 			args: []string{"-uinitcmd=echo foobar fuzz", "-defaultsh=", "github.com/u-root/u-root/cmds/core/init", "github.com/u-root/u-root/cmds/core/echo"},
-			err:  nil,
 			validators: []itest.ArchiveValidator{
 				itest.HasRecord{R: cpio.Symlink("bin/uinit", "../bbin/echo")},
 				itest.HasContent{
@@ -133,8 +154,12 @@ func TestUrootCmdline(t *testing.T) {
 		},
 		{
 			name: "binary build",
-			args: []string{"-build=binary", "-defaultsh=", "github.com/u-root/u-root/cmds/core/init", "github.com/u-root/u-root/cmds/core/echo"},
-			err:  nil,
+			args: []string{
+				"-build=binary",
+				"-defaultsh=",
+				"github.com/u-root/u-root/cmds/core/init",
+				"github.com/u-root/u-root/cmds/core/echo",
+			},
 			validators: []itest.ArchiveValidator{
 				itest.HasFile{Path: "bin/init"},
 				itest.HasFile{Path: "bin/echo"},
@@ -143,23 +168,41 @@ func TestUrootCmdline(t *testing.T) {
 		},
 		{
 			name: "hosted mode",
-			args: append([]string{"-base=/dev/null", "-defaultsh=", "-initcmd="}, twocmds...),
+			args: []string{
+				"-base=/dev/null",
+				"-defaultsh=",
+				"-initcmd=",
+				"github.com/u-root/u-root/cmds/core/ls",
+				"github.com/u-root/u-root/cmds/core/init",
+			},
 		},
 		{
 			name: "AMD64 build",
 			env:  []string{"GOARCH=amd64"},
 			args: []string{
+				"-defaultsh=echo",
+				"github.com/u-root/u-root/cmds/core/echo",
 				"github.com/u-root/u-root/cmds/core/init",
-				"github.com/u-root/u-root/cmds/core/elvish",
+			},
+		},
+		{
+			name: "AMD64 build with temp dir",
+			env:  []string{"GOARCH=amd64"},
+			args: []string{
+				"--keep-tmp-dir",
+				"--defaultsh=echo",
 				"github.com/u-root/u-root/cmds/core/echo",
+				"github.com/u-root/u-root/cmds/core/init",
 			},
+			exitCode:   1,
+			wantOutput: hasTempDir,
 		},
 		{
 			name: "ARM7 build",
 			env:  []string{"GOARCH=arm", "GOARM=7"},
 			args: []string{
+				"-defaultsh=",
 				"github.com/u-root/u-root/cmds/core/init",
-				"github.com/u-root/u-root/cmds/core/elvish",
 				"github.com/u-root/u-root/cmds/core/echo",
 			},
 		},
@@ -167,8 +210,8 @@ func TestUrootCmdline(t *testing.T) {
 			name: "ARM64 build",
 			env:  []string{"GOARCH=arm64"},
 			args: []string{
+				"-defaultsh=",
 				"github.com/u-root/u-root/cmds/core/init",
-				"github.com/u-root/u-root/cmds/core/elvish",
 				"github.com/u-root/u-root/cmds/core/echo",
 			},
 		},
@@ -176,11 +219,50 @@ func TestUrootCmdline(t *testing.T) {
 			name: "RISCV 64bit build",
 			env:  []string{"GOARCH=riscv64"},
 			args: []string{
+				"-defaultsh=",
 				"github.com/u-root/u-root/cmds/core/init",
-				"github.com/u-root/u-root/cmds/core/elvish",
 				"github.com/u-root/u-root/cmds/core/echo",
 			},
 		},
+		{
+			name: "build invalid",
+			args: []string{
+				"-build=source",
+				"github.com/u-root/u-root/cmds/core/init",
+				"github.com/u-root/u-root/cmds/core/echo",
+			},
+			exitCode: 1,
+		},
+		{
+			name: "build invalid",
+			args: []string{
+				"-build=source",
+				"github.com/u-root/u-root/cmds/core/init",
+				"github.com/u-root/u-root/cmds/core/echo",
+			},
+			exitCode: 1,
+		},
+		{
+			name: "arch invalid preserves temp dir",
+			env:  []string{"GOARCH=doesnotexist"},
+			args: []string{
+				"--defaultsh=echo",
+				"github.com/u-root/u-root/cmds/core/echo",
+				"github.com/u-root/u-root/cmds/core/init",
+			},
+			exitCode:   1,
+			wantOutput: hasTempDir,
+		},
+		{
+			name: "specify temp dir",
+			args: []string{
+				"--tmp-dir=" + tempDir,
+				"github.com/u-root/u-root/cmds/core/echo",
+				"github.com/u-root/u-root/cmds/core/init",
+			},
+			exitCode:   1,
+			wantOutput: dirExists(tempDir),
+		},
 	}
 
 	for _, tt := range append(noCmdTests, bareTests...) {
@@ -188,22 +270,35 @@ func TestUrootCmdline(t *testing.T) {
 		t.Run(tt.name, func(t *testing.T) {
 			var g errgroup.Group
 			var f1, f2 *os.File
+			var out string
 			var sum1, sum2 []byte
 
 			g.Go(func() error {
 				var err error
-				f1, sum1, err = buildIt(t, execPath, tt.args, tt.env, tt.err, gocoverdir)
+				f1, out, sum1, err = buildIt(t, execPath, tt.args, tt.env, gocoverdir)
 				return err
 			})
 
 			g.Go(func() error {
 				var err error
-				f2, sum2, err = buildIt(t, execPath, tt.args, tt.env, tt.err, gocoverdir)
+				f2, _, sum2, err = buildIt(t, execPath, tt.args, tt.env, gocoverdir)
 				return err
 			})
 
-			if err := g.Wait(); err != nil {
-				t.Fatal(err)
+			err := g.Wait()
+			if tt.wantOutput != nil {
+				tt.wantOutput(t, out)
+			}
+
+			var exitErr *exec.ExitError
+			if errors.As(err, &exitErr) {
+				if ec := exitErr.Sys().(syscall.WaitStatus).ExitStatus(); ec != tt.exitCode {
+					t.Errorf("mkuimage exit code = %d, want %d", ec, tt.exitCode)
+				}
+				return
+			} else if err != nil {
+				t.Errorf("mkuimage failed: %v", err)
+				return
 			}
 
 			a, err := itest.ReadArchive(f1.Name())
@@ -225,11 +320,11 @@ func TestUrootCmdline(t *testing.T) {
 	}
 }
 
-func buildIt(t *testing.T, execPath string, args, env []string, want error, gocoverdir string) (*os.File, []byte, error) {
+func buildIt(t *testing.T, execPath string, args, env []string, gocoverdir string) (*os.File, string, []byte, error) {
 	t.Helper()
 	initramfs, err := os.CreateTemp(t.TempDir(), "u-root-")
 	if err != nil {
-		return nil, nil, err
+		return nil, "", nil, err
 	}
 
 	// Use the u-root command outside of the $GOPATH tree to make sure it
@@ -239,19 +334,18 @@ func buildIt(t *testing.T, execPath string, args, env []string, want error, goco
 
 	c := exec.Command(execPath, args...)
 	c.Env = append(os.Environ(), env...)
-	c.Env = append(c.Env, golang.Default().Env()...)
 	c.Env = append(c.Env, "GOCOVERDIR="+gocoverdir)
-	if out, err := c.CombinedOutput(); err != want {
-		return nil, nil, fmt.Errorf("Error: %v\nOutput:\n%s", err, out)
-	} else if err != nil {
-		return initramfs, nil, err
+	out, err := c.CombinedOutput()
+	t.Logf("Output:\n%s", out)
+	if err != nil {
+		return nil, string(out), nil, err
 	}
 
 	h1 := sha256.New()
 	if _, err := io.Copy(h1, initramfs); err != nil {
-		return nil, nil, err
+		return nil, string(out), nil, err
 	}
-	return initramfs, h1.Sum(nil), nil
+	return initramfs, string(out), h1.Sum(nil), nil
 }
 
 func TestCheckArgs(t *testing.T) {
diff --git a/dependencies.go b/dependencies.go
index 5afec72..cadf10b 100644
--- a/dependencies.go
+++ b/dependencies.go
@@ -9,7 +9,6 @@ package mkuimage
 import (
 	_ "github.com/u-root/u-root/cmds/core/dhclient"
 	_ "github.com/u-root/u-root/cmds/core/echo"
-	_ "github.com/u-root/u-root/cmds/core/elvish"
 	_ "github.com/u-root/u-root/cmds/core/init"
 	_ "github.com/u-root/u-root/cmds/core/ip"
 	_ "github.com/u-root/u-root/cmds/core/ls"
diff --git a/go.mod b/go.mod
index 2f12558..bb1c1b2 100644
--- a/go.mod
+++ b/go.mod
@@ -19,7 +19,6 @@ require (
 	github.com/josharian/native v1.1.0 // indirect
 	github.com/klauspost/compress v1.17.4 // indirect
 	github.com/klauspost/pgzip v1.2.6 // indirect
-	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/mdlayher/packet v1.1.2 // indirect
 	github.com/mdlayher/socket v0.5.0 // indirect
 	github.com/pierrec/lz4/v4 v4.1.14 // indirect
@@ -27,8 +26,6 @@ require (
 	github.com/ulikunitz/xz v0.5.11 // indirect
 	github.com/vishvananda/netlink v1.2.1-beta.2 // indirect
 	github.com/vishvananda/netns v0.0.4 // indirect
-	golang.org/dl v0.0.0-20240206215513-68cc34b6ca6f // indirect
 	golang.org/x/mod v0.14.0 // indirect
 	golang.org/x/net v0.20.0 // indirect
-	src.elv.sh v0.16.0-rc1.0.20220116211855-fda62502ad7f // indirect
 )
diff --git a/go.sum b/go.sum
index 2ef9d30..bfcee98 100644
--- a/go.sum
+++ b/go.sum
@@ -1,6 +1,5 @@
 github.com/Netflix/go-expect v0.0.0-20220104043353-73e0943537d2 h1:+vx7roKuyA63nhn5WAunQHLTznkw5W8b1Xc0dNjp83s=
 github.com/Netflix/go-expect v0.0.0-20220104043353-73e0943537d2/go.mod h1:HBCaDeC1lPdgDeDbhX8XFpy1jqjK0IBG8W5K+xYqA0w=
-github.com/creack/pty v1.1.15/go.mod h1:MOBLtS5ELjhRRrroQr9kyvTxUAFNvYEK993ew/Vr4O4=
 github.com/creack/pty v1.1.21 h1:1/QdRyBaHHJP61QkWMXlOIBfsgdDeeKfK8SYVUWJKf0=
 github.com/creack/pty v1.1.21/go.mod h1:MOBLtS5ELjhRRrroQr9kyvTxUAFNvYEK993ew/Vr4O4=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
@@ -25,7 +24,6 @@ github.com/klauspost/compress v1.17.4 h1:Ej5ixsIri7BrIjBkRZLTo6ghwrEtHFk7ijlczPW
 github.com/klauspost/compress v1.17.4/go.mod h1:/dCuZOvVtNoHsyb+cuJD3itjs3NbnF6KH9zAO4BDxPM=
 github.com/klauspost/pgzip v1.2.6 h1:8RXeL5crjEUFnR2/Sn6GJNWtSQ3Dk8pq4CL3jvdDyjU=
 github.com/klauspost/pgzip v1.2.6/go.mod h1:Ch1tH69qFZu15pkjo5kYi6mth2Zzwzt50oCQKQE9RUs=
-github.com/mattn/go-isatty v0.0.14/go.mod h1:7GGIvUiUoEMVVmxf/4nioHXj79iQHKdU27kJ6hsGG94=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/mdlayher/packet v1.1.2 h1:3Up1NG6LZrsgDVn6X4L9Ge/iyRyxFEFD9o6Pr3Q1nQY=
@@ -55,10 +53,6 @@ github.com/vishvananda/netlink v1.2.1-beta.2/go.mod h1:twkDnbuQxJYemMlGd4JFIcuhg
 github.com/vishvananda/netns v0.0.0-20200728191858-db3c7e526aae/go.mod h1:DD4vA1DwXk04H54A1oHXtwZmA0grkVMdPxx/VGLCah0=
 github.com/vishvananda/netns v0.0.4 h1:Oeaw1EM2JMxD51g9uhtC0D7erkIjgmj8+JZc26m1YX8=
 github.com/vishvananda/netns v0.0.4/go.mod h1:SpkAiCQRtJ6TvvxPnOSyH3BMl6unz3xZlaprSwhNNJM=
-go.etcd.io/bbolt v1.3.6 h1:/ecaJf0sk1l4l6V4awd65v2C3ILy7MSj+s/x1ADCIMU=
-go.etcd.io/bbolt v1.3.6/go.mod h1:qXsaaIqmgQH0T+OPdb99Bf+PKfBBQVAdyD6TY9G8XM4=
-golang.org/dl v0.0.0-20240206215513-68cc34b6ca6f h1:IWM5GianvyTx750h5TRfWms43pREUt1gQ0ZdVQdoiOM=
-golang.org/dl v0.0.0-20240206215513-68cc34b6ca6f/go.mod h1:fwQ+hlTD8I6TIzOGkQqxQNfE2xqR+y7SzGaDkksVFkw=
 golang.org/x/exp v0.0.0-20231219180239-dc181d75b848 h1:+iq7lrkxmFNBM7xx+Rae2W6uyPfhPeDWD+n+JgppptE=
 golang.org/x/exp v0.0.0-20231219180239-dc181d75b848/go.mod h1:iRJReGqOEeBhDZGkGbynYwcHlctCvnjTYIamk7uXpHI=
 golang.org/x/mod v0.14.0 h1:dGoOF9QVLYng8IHTm7BAyWqCqSheQ5pYWGhzW00YJr0=
@@ -69,10 +63,6 @@ golang.org/x/sync v0.6.0 h1:5BMeUDZ7vkXGfEr1x9B4bRcTH4lpkTkpdh0T/J+qjbQ=
 golang.org/x/sync v0.6.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.0.0-20200217220822-9197077df867/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200728102440-3e129f6d46b1/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200923182605-d9f96fdee20d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20211205182925-97ca703d548d/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.16.0 h1:xWw16ngr6ZMtmxDyKyIgsE93KNKz5HKmMa3b8ALHidU=
 golang.org/x/sys v0.16.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/tools v0.17.0 h1:FvmRgNOcs3kOa+T20R1uhfP9F6HgG2mfxDv1vrx1Htc=
diff --git a/uimage/builder/binary_test.go b/uimage/builder/binary_test.go
index 8b881c7..2697684 100644
--- a/uimage/builder/binary_test.go
+++ b/uimage/builder/binary_test.go
@@ -18,7 +18,6 @@ func TestBinaryBuild(t *testing.T) {
 		Env: golang.Default(golang.DisableCGO()),
 		Packages: []string{
 			"../../cmd/mkuimage",
-			"github.com/u-root/u-root/cmds/core/elvish",
 			"github.com/u-root/u-root/cmds/core/init",
 			"cmd/test2json",
 		},
@@ -31,7 +30,6 @@ func TestBinaryBuild(t *testing.T) {
 	}
 
 	mustContain := []string{
-		"bin/elvish",
 		"bin/mkuimage",
 		"bin/test2json",
 		"bin/init",
diff --git a/uimage/mkuimage/cmd.go b/uimage/mkuimage/cmd.go
new file mode 100644
index 0000000..d91efe3
--- /dev/null
+++ b/uimage/mkuimage/cmd.go
@@ -0,0 +1,92 @@
+// Copyright 2024 the u-root Authors. All rights reserved
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mkuimage
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"runtime"
+	"strings"
+
+	"github.com/u-root/mkuimage/uimage"
+	"github.com/u-root/mkuimage/uimage/builder"
+	"github.com/u-root/uio/llog"
+)
+
+var recommendedVersions = []string{
+	"go1.20",
+	"go1.21",
+	"go1.22",
+}
+
+func isRecommendedVersion(v string) bool {
+	for _, r := range recommendedVersions {
+		if strings.HasPrefix(v, r) {
+			return true
+		}
+	}
+	return false
+}
+
+// CreateUimage creates a uimage from the given base modifiers and flags.
+func CreateUimage(l *llog.Logger, base []uimage.Modifier, f *Flags, args []string) error {
+	keepTempDir := f.KeepTempDir
+	if f.TempDir == "" {
+		var err error
+		f.TempDir, err = os.MkdirTemp("", "u-root")
+		if err != nil {
+			return err
+		}
+		defer func() {
+			if keepTempDir {
+				l.Infof("Keeping temp dir %s", f.TempDir)
+			} else {
+				os.RemoveAll(f.TempDir)
+			}
+		}()
+	} else if _, err := os.Stat(f.TempDir); os.IsNotExist(err) {
+		if err := os.MkdirAll(f.TempDir, 0o755); err != nil {
+			return fmt.Errorf("temporary directory %q did not exist; tried to mkdir but failed: %v", f.TempDir, err)
+		}
+	}
+
+	// Set defaults.
+	more, err := f.Modifiers(args...)
+	if err != nil {
+		return err
+	}
+
+	opts, err := uimage.OptionsFor(append(base, more...)...)
+	if err != nil {
+		return err
+	}
+
+	env := opts.Env
+
+	l.Infof("Build environment: %s", env)
+	if env.GOOS != "linux" {
+		l.Warnf("GOOS is not linux. Did you mean to set GOOS=linux?")
+	}
+	v, err := env.Version()
+	if err != nil {
+		l.Infof("Could not get environment's Go version, using runtime's version: %v", err)
+		v = runtime.Version()
+	}
+	if !isRecommendedVersion(v) {
+		l.Warnf(`You are not using one of the recommended Go versions (have = %s, recommended = %v).
+			Some packages may not compile.
+			Go to https://golang.org/doc/install to find out how to install a newer version of Go,
+			or use https://godoc.org/golang.org/dl/%s to install an additional version of Go.`,
+			v, recommendedVersions, recommendedVersions[0])
+	}
+
+	err = opts.Create(l)
+	if errors.Is(err, builder.ErrBusyboxFailed) {
+		l.Errorf("Preserving temp dir due to busybox build error")
+		keepTempDir = true
+	}
+	return err
+}
diff --git a/uimage/uflags/uflags.go b/uimage/mkuimage/uflags.go
similarity index 98%
rename from uimage/uflags/uflags.go
rename to uimage/mkuimage/uflags.go
index 8121dab..317c96d 100644
--- a/uimage/uflags/uflags.go
+++ b/uimage/mkuimage/uflags.go
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package uflags defines mkuimage flags.
-package uflags
+// Package mkuimage defines mkuimage flags and creation function.
+package mkuimage
 
 import (
 	"flag"
diff --git a/uimage/uflags/uflags_test.go b/uimage/mkuimage/uflags_test.go
similarity index 97%
rename from uimage/uflags/uflags_test.go
rename to uimage/mkuimage/uflags_test.go
index 153355d..2abc344 100644
--- a/uimage/uflags/uflags_test.go
+++ b/uimage/mkuimage/uflags_test.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package uflags
+package mkuimage
 
 import (
 	"errors"