diff --git a/internal/homesick/cli/cli_test.go b/internal/homesick/cli/cli_test.go
index ba40dfa..5363b11 100644
--- a/internal/homesick/cli/cli_test.go
+++ b/internal/homesick/cli/cli_test.go
@@ -5,9 +5,13 @@ import (
 	"os"
 	"path/filepath"
 	"testing"
+	"time"
 
 	"git.hrafn.xyz/aether/gosick/internal/homesick/cli"
 	"git.hrafn.xyz/aether/gosick/internal/homesick/version"
+	git "github.com/go-git/go-git/v5"
+	"github.com/go-git/go-git/v5/config"
+	"github.com/go-git/go-git/v5/plumbing/object"
 	"github.com/stretchr/testify/require"
 	"github.com/stretchr/testify/suite"
 )
@@ -32,6 +36,32 @@ func (s *CLISuite) SetupTest() {
 	s.stderr = &bytes.Buffer{}
 }
 
+func (s *CLISuite) createCastleRepo(castle string) string {
+	castleRoot := filepath.Join(s.homeDir, ".homesick", "repos", castle)
+	repo, err := git.PlainInit(castleRoot, false)
+	require.NoError(s.T(), err)
+
+	filePath := filepath.Join(castleRoot, "home", ".vimrc")
+	require.NoError(s.T(), os.MkdirAll(filepath.Dir(filePath), 0o755))
+	require.NoError(s.T(), os.WriteFile(filePath, []byte("set number\n"), 0o644))
+
+	wt, err := repo.Worktree()
+	require.NoError(s.T(), err)
+	_, err = wt.Add("home/.vimrc")
+	require.NoError(s.T(), err)
+	_, err = wt.Commit("initial", &git.CommitOptions{Author: &object.Signature{
+		Name:  "Behavior Test",
+		Email: "behavior@test.local",
+		When:  time.Now(),
+	}})
+	require.NoError(s.T(), err)
+
+	_, err = repo.CreateRemote(&config.RemoteConfig{Name: "origin", URLs: []string{"git://example.com/test.git"}})
+	require.NoError(s.T(), err)
+
+	return castleRoot
+}
+
 func (s *CLISuite) TestRun_VersionAliases() {
 	for _, args := range [][]string{{"-v"}, {"--version"}, {"version"}} {
 		s.stdout.Reset()
@@ -191,3 +221,52 @@ func (s *CLISuite) TestRun_Commit_PositionalMessageCompatibility() {
 	require.Contains(s.T(), s.stdout.String(), "git commit -m behavior-suite-commit")
 	require.Empty(s.T(), s.stderr.String())
 }
+
+func (s *CLISuite) TestRun_List_NoArguments() {
+	s.createCastleRepo("dotfiles")
+
+	exitCode := cli.Run([]string{"list"}, s.stdout, s.stderr)
+
+	require.Equal(s.T(), 0, exitCode)
+	require.Contains(s.T(), s.stdout.String(), "dotfiles")
+	require.Empty(s.T(), s.stderr.String())
+}
+
+func (s *CLISuite) TestRun_Generate_CreatesNewCastle() {
+	castlePath := filepath.Join(s.T().TempDir(), "my-castle")
+
+	exitCode := cli.Run([]string{"generate", castlePath}, s.stdout, s.stderr)
+
+	require.Equal(s.T(), 0, exitCode)
+	require.DirExists(s.T(), filepath.Join(castlePath, ".git"))
+	require.DirExists(s.T(), filepath.Join(castlePath, "home"))
+}
+
+func (s *CLISuite) TestRun_Clone_WithoutArgs() {
+	exitCode := cli.Run([]string{"clone"}, s.stdout, s.stderr)
+
+	// Clone requires arguments, should fail
+	require.NotEqual(s.T(), 0, exitCode)
+}
+
+func (s *CLISuite) TestRun_Status_DefaultCastle() {
+	castleRoot := s.createCastleRepo("dotfiles")
+	require.NoError(s.T(), os.WriteFile(filepath.Join(castleRoot, "home", ".vimrc"), []byte("changed\n"), 0o644))
+
+	exitCode := cli.Run([]string{"status"}, s.stdout, s.stderr)
+
+	require.Equal(s.T(), 0, exitCode)
+	require.Contains(s.T(), s.stdout.String(), "modified:")
+	require.Empty(s.T(), s.stderr.String())
+}
+
+func (s *CLISuite) TestRun_Diff_DefaultCastle() {
+	castleRoot := s.createCastleRepo("dotfiles")
+	require.NoError(s.T(), os.WriteFile(filepath.Join(castleRoot, "home", ".vimrc"), []byte("changed\n"), 0o644))
+
+	exitCode := cli.Run([]string{"diff"}, s.stdout, s.stderr)
+
+	require.Equal(s.T(), 0, exitCode)
+	require.Contains(s.T(), s.stdout.String(), "diff --git")
+	require.Empty(s.T(), s.stderr.String())
+}
diff --git a/internal/homesick/core/core_test.go b/internal/homesick/core/core_test.go
index 1da9dff..0ff0220 100644
--- a/internal/homesick/core/core_test.go
+++ b/internal/homesick/core/core_test.go
@@ -2,6 +2,7 @@ package core
 
 import (
 	"bytes"
+	"path/filepath"
 	"testing"
 )
 
@@ -47,3 +48,29 @@ func TestDeriveDestination(t *testing.T) {
 		})
 	}
 }
+
+func TestNewInitializesApp(t *testing.T) {
+	stdout := &bytes.Buffer{}
+	stderr := &bytes.Buffer{}
+
+	app, err := New(stdout, stderr)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if app == nil {
+		t.Fatal("expected app instance")
+	}
+
+	if app.Stdout != stdout {
+		t.Fatal("expected stdout writer to be assigned")
+	}
+	if app.Stderr != stderr {
+		t.Fatal("expected stderr writer to be assigned")
+	}
+	if app.HomeDir == "" {
+		t.Fatal("expected home directory to be set")
+	}
+	if app.ReposDir != filepath.Join(app.HomeDir, ".homesick", "repos") {
+		t.Fatalf("unexpected repos dir: %q", app.ReposDir)
+	}
+}
diff --git a/internal/homesick/core/exec_test.go b/internal/homesick/core/exec_test.go
index 7aa284f..3f0412a 100644
--- a/internal/homesick/core/exec_test.go
+++ b/internal/homesick/core/exec_test.go
@@ -88,3 +88,22 @@ func (s *ExecSuite) TestExec_PretendDoesNotExecuteCommand() {
 	require.NoFileExists(s.T(), target)
 	require.Contains(s.T(), s.stdout.String(), "Would execute")
 }
+
+func (s *ExecSuite) TestExecAll_RequiresCommand() {
+	err := s.app.ExecAll(nil)
+	require.Error(s.T(), err)
+	require.Contains(s.T(), err.Error(), "exec_all requires COMMAND")
+}
+
+func (s *ExecSuite) TestExecAll_NoReposDirIsNoop() {
+	missingRepos := filepath.Join(s.T().TempDir(), "missing", "repos")
+	app := &core.App{
+		HomeDir:  s.homeDir,
+		ReposDir: missingRepos,
+		Stdout:   s.stdout,
+		Stderr:   s.stderr,
+	}
+
+	err := app.ExecAll([]string{"echo hi"})
+	require.NoError(s.T(), err)
+}
diff --git a/internal/homesick/core/helpers_test.go b/internal/homesick/core/helpers_test.go
new file mode 100644
index 0000000..a2db849
--- /dev/null
+++ b/internal/homesick/core/helpers_test.go
@@ -0,0 +1,245 @@
+package core
+
+import (
+	"bytes"
+	"errors"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+type errReader struct{}
+
+func (errReader) Read(_ []byte) (int, error) {
+	return 0, errors.New("boom")
+}
+
+func TestRunGitPretendWritesStatus(t *testing.T) {
+	stdout := &bytes.Buffer{}
+	app := &App{Stdout: stdout, Stderr: bytes.NewBuffer(nil), Pretend: true}
+
+	err := app.runGit("/tmp", "status")
+	require.NoError(t, err)
+	require.Contains(t, stdout.String(), "Would execute git status in /tmp")
+}
+
+func TestActionVerb(t *testing.T) {
+	app := &App{Pretend: true}
+	require.Equal(t, "Would execute", app.actionVerb())
+
+	app.Pretend = false
+	require.Equal(t, "Executing", app.actionVerb())
+}
+
+func TestSayStatusHonorsQuiet(t *testing.T) {
+	stdout := &bytes.Buffer{}
+	app := &App{Stdout: stdout, Quiet: true}
+	app.sayStatus("git", "status")
+	require.Empty(t, stdout.String())
+
+	app.Quiet = false
+	app.sayStatus("git", "status")
+	require.Contains(t, stdout.String(), "git: status")
+}
+
+func TestUnlinkPath(t *testing.T) {
+	t.Run("missing destination", func(t *testing.T) {
+		err := unlinkPath(filepath.Join(t.TempDir(), "does-not-exist"))
+		require.NoError(t, err)
+	})
+
+	t.Run("regular file is preserved", func(t *testing.T) {
+		dir := t.TempDir()
+		target := filepath.Join(dir, "regular")
+		require.NoError(t, os.WriteFile(target, []byte("x"), 0o644))
+
+		err := unlinkPath(target)
+		require.NoError(t, err)
+		require.FileExists(t, target)
+	})
+
+	t.Run("symlink is removed", func(t *testing.T) {
+		dir := t.TempDir()
+		source := filepath.Join(dir, "source")
+		destination := filepath.Join(dir, "dest")
+		require.NoError(t, os.WriteFile(source, []byte("x"), 0o644))
+		require.NoError(t, os.Symlink(source, destination))
+
+		err := unlinkPath(destination)
+		require.NoError(t, err)
+		_, statErr := os.Lstat(destination)
+		require.ErrorIs(t, statErr, os.ErrNotExist)
+	})
+}
+
+func TestLinkPath(t *testing.T) {
+	t.Run("existing symlink to same source is no-op", func(t *testing.T) {
+		dir := t.TempDir()
+		source := filepath.Join(dir, "source")
+		destination := filepath.Join(dir, "dest")
+		require.NoError(t, os.WriteFile(source, []byte("x"), 0o644))
+
+		absSource, err := filepath.Abs(source)
+		require.NoError(t, err)
+		require.NoError(t, os.Symlink(absSource, destination))
+
+		app := &App{Stdout: bytes.NewBuffer(nil), Stderr: bytes.NewBuffer(nil)}
+		err = app.linkPath(source, destination)
+		require.NoError(t, err)
+	})
+
+	t.Run("conflict without force errors", func(t *testing.T) {
+		dir := t.TempDir()
+		source := filepath.Join(dir, "source")
+		destination := filepath.Join(dir, "dest")
+		require.NoError(t, os.WriteFile(source, []byte("x"), 0o644))
+		require.NoError(t, os.WriteFile(destination, []byte("existing"), 0o644))
+
+		app := &App{Stdout: bytes.NewBuffer(nil), Stderr: bytes.NewBuffer(nil)}
+		err := app.linkPath(source, destination)
+		require.Error(t, err)
+		require.Contains(t, err.Error(), "exists")
+	})
+
+	t.Run("force replaces existing destination", func(t *testing.T) {
+		dir := t.TempDir()
+		source := filepath.Join(dir, "source")
+		destination := filepath.Join(dir, "dest")
+		require.NoError(t, os.WriteFile(source, []byte("x"), 0o644))
+		require.NoError(t, os.WriteFile(destination, []byte("existing"), 0o644))
+
+		app := &App{Stdout: bytes.NewBuffer(nil), Stderr: bytes.NewBuffer(nil), Force: true}
+		err := app.linkPath(source, destination)
+		require.NoError(t, err)
+
+		info, statErr := os.Lstat(destination)
+		require.NoError(t, statErr)
+		require.True(t, info.Mode()&os.ModeSymlink != 0)
+	})
+}
+
+func TestReadSubdirsAndMatchesIgnoredDir(t *testing.T) {
+	dir := t.TempDir()
+	meta := filepath.Join(dir, ".homesick_subdir")
+	require.NoError(t, os.WriteFile(meta, []byte(" .config/myapp \n\n"), 0o644))
+
+	subdirs, err := readSubdirs(meta)
+	require.NoError(t, err)
+	require.Equal(t, []string{filepath.Clean(".config/myapp")}, subdirs)
+
+	castleHome := filepath.Join(dir, "castle", "home")
+	candidate := filepath.Join(castleHome, ".config")
+	ignored, err := matchesIgnoredDir(castleHome, candidate, subdirs)
+	require.NoError(t, err)
+	require.True(t, ignored)
+
+	notIgnored, err := matchesIgnoredDir(castleHome, filepath.Join(castleHome, ".vim"), subdirs)
+	require.NoError(t, err)
+	require.False(t, notIgnored)
+}
+
+func TestPullAndPushDefaultCastlePretend(t *testing.T) {
+	dir := t.TempDir()
+	stdout := &bytes.Buffer{}
+	app := &App{
+		HomeDir:  dir,
+		ReposDir: filepath.Join(dir, ".homesick", "repos"),
+		Stdout:   stdout,
+		Stderr:   bytes.NewBuffer(nil),
+		Pretend:  true,
+	}
+
+	require.NoError(t, app.Pull(""))
+	require.NoError(t, app.Push(""))
+
+	out := stdout.String()
+	require.Contains(t, out, "git pull")
+	require.Contains(t, out, "git push")
+	require.Contains(t, out, filepath.Join(app.ReposDir, "dotfiles"))
+}
+
+func TestGenerateRequiresPath(t *testing.T) {
+	app := &App{Stdout: bytes.NewBuffer(nil), Stderr: bytes.NewBuffer(nil)}
+	err := app.Generate("   ")
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "generate requires PATH")
+}
+
+func TestLinkAndUnlinkDefaultCastle(t *testing.T) {
+	dir := t.TempDir()
+	homeDir := filepath.Join(dir, "home")
+	reposDir := filepath.Join(homeDir, ".homesick", "repos")
+
+	castleHome := filepath.Join(reposDir, "dotfiles", "home")
+	require.NoError(t, os.MkdirAll(castleHome, 0o755))
+	source := filepath.Join(castleHome, ".vimrc")
+	require.NoError(t, os.WriteFile(source, []byte("set number\n"), 0o644))
+
+	app := &App{HomeDir: homeDir, ReposDir: reposDir, Stdout: bytes.NewBuffer(nil), Stderr: bytes.NewBuffer(nil)}
+	require.NoError(t, app.Link(""))
+
+	destination := filepath.Join(homeDir, ".vimrc")
+	info, err := os.Lstat(destination)
+	require.NoError(t, err)
+	require.True(t, info.Mode()&os.ModeSymlink != 0)
+
+	require.NoError(t, app.Unlink(""))
+	_, err = os.Lstat(destination)
+	require.ErrorIs(t, err, os.ErrNotExist)
+}
+
+func TestLinkAndUnlinkCastleMissingError(t *testing.T) {
+	dir := t.TempDir()
+	app := &App{
+		HomeDir:  filepath.Join(dir, "home"),
+		ReposDir: filepath.Join(dir, "home", ".homesick", "repos"),
+		Stdout:   bytes.NewBuffer(nil),
+		Stderr:   bytes.NewBuffer(nil),
+	}
+
+	err := app.LinkCastle("missing")
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "could not symlink")
+
+	err = app.UnlinkCastle("missing")
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "could not symlink")
+}
+
+func TestConfirmDestroyResponses(t *testing.T) {
+	stdout := &bytes.Buffer{}
+	app := &App{Stdout: stdout, Stdin: strings.NewReader("yes\n")}
+
+	ok, err := app.confirmDestroy("dotfiles")
+	require.NoError(t, err)
+	require.True(t, ok)
+	require.Contains(t, stdout.String(), "Destroy castle \"dotfiles\"?")
+
+	stdout.Reset()
+	app.Stdin = strings.NewReader("n\n")
+	ok, err = app.confirmDestroy("dotfiles")
+	require.NoError(t, err)
+	require.False(t, ok)
+}
+
+func TestConfirmDestroyReadError(t *testing.T) {
+	app := &App{Stdout: bytes.NewBuffer(nil), Stdin: errReader{}}
+	ok, err := app.confirmDestroy("dotfiles")
+	require.Error(t, err)
+	require.False(t, ok)
+}
+
+func TestExecAllWrapsCastleError(t *testing.T) {
+	dir := t.TempDir()
+	homeDir := filepath.Join(dir, "home")
+	reposDir := filepath.Join(homeDir, ".homesick", "repos")
+	require.NoError(t, os.MkdirAll(filepath.Join(reposDir, "broken", ".git"), 0o755))
+
+	app := &App{HomeDir: homeDir, ReposDir: reposDir, Stdout: bytes.NewBuffer(nil), Stderr: bytes.NewBuffer(nil)}
+	err := app.ExecAll([]string{"exit 3"})
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "exec_all failed for \"broken\"")
+}
diff --git a/internal/homesick/core/pull_test.go b/internal/homesick/core/pull_test.go
index eacd224..82234e0 100644
--- a/internal/homesick/core/pull_test.go
+++ b/internal/homesick/core/pull_test.go
@@ -140,3 +140,17 @@ func (s *PullSuite) TestPullAll_PrintsCastlePrefixes() {
 	require.Contains(s.T(), stdout.String(), "alpha:")
 	require.Contains(s.T(), stdout.String(), "zeta:")
 }
+
+func (s *PullSuite) TestPullAll_QuietSuppressesCastlePrefixes() {
+	require.NoError(s.T(), os.MkdirAll(filepath.Join(s.reposDir, "alpha", ".git"), 0o755))
+	require.NoError(s.T(), os.MkdirAll(filepath.Join(s.reposDir, "zeta", ".git"), 0o755))
+
+	stdout := &bytes.Buffer{}
+	s.app.Stdout = stdout
+	s.app.Quiet = true
+	s.app.Pretend = true
+
+	require.NoError(s.T(), s.app.PullAll())
+	require.NotContains(s.T(), stdout.String(), "alpha:")
+	require.NotContains(s.T(), stdout.String(), "zeta:")
+}
diff --git a/internal/homesick/version/version_test.go b/internal/homesick/version/version_test.go
new file mode 100644
index 0000000..6070c8d
--- /dev/null
+++ b/internal/homesick/version/version_test.go
@@ -0,0 +1,21 @@
+package version
+
+import (
+	"regexp"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestStringConstant(t *testing.T) {
+	// Test that the version constant is not empty
+	assert.NotEmpty(t, String, "version.String should not be empty")
+}
+
+func TestStringMatchesSemVer(t *testing.T) {
+	// Test that the version string matches semantic versioning pattern (major.minor.patch)
+	semverPattern := `^\d+\.\d+\.\d+$`
+	matched, err := regexp.MatchString(semverPattern, String)
+	assert.NoError(t, err, "regex should be valid")
+	assert.True(t, matched, "version.String should match semantic versioning pattern (major.minor.patch), got: %s", String)
+}