diff --git a/installer/apt_installer.go b/installer/apt_installer.go
index f6ae936..645bc00 100644
--- a/installer/apt_installer.go
+++ b/installer/apt_installer.go
@@ -6,6 +6,7 @@ import (
 )
 
 type AptInstaller struct {
+	InstallerBase
 	Config         *appconfig.AppConfig
 	Info           *appconfig.InstallerData
 	PackageManager PackageManager
@@ -23,7 +24,7 @@ const (
 // Install implements IInstaller.
 func (i *AptInstaller) Install() error {
 	name := *i.Info.Name
-	err := utils.RunCmdPassThrough(i.Info.Environ(), string(i.PackageManager), "update")
+	err := i.RunCmdPassThrough(string(i.PackageManager), "update")
 	if err != nil {
 		return err
 	}
@@ -31,7 +32,7 @@ func (i *AptInstaller) Install() error {
 	if i.PackageManager == PackageManagerApk {
 		install = "add"
 	}
-	return utils.RunCmdPassThrough(i.Info.Environ(), string(i.PackageManager), install, i.getConfirmArg(), name)
+	return i.RunCmdPassThrough(string(i.PackageManager), install, i.getConfirmArg(), name)
 }
 
 func (i *AptInstaller) getConfirmArg() string {
@@ -44,28 +45,31 @@ func (i *AptInstaller) getConfirmArg() string {
 
 // Update implements IInstaller.
 func (i *AptInstaller) Update() error {
-	return utils.RunCmdPassThrough(i.Info.Environ(), string(i.PackageManager), "upgrade", i.getConfirmArg(), *i.Info.Name)
+	return i.RunCmdPassThrough(string(i.PackageManager), "upgrade", i.getConfirmArg(), *i.Info.Name)
 }
 
 // CheckNeedsUpdate implements IInstaller.
-func (i *AptInstaller) CheckNeedsUpdate() (error, bool) {
-	if i.GetData().CheckHasUpdate != nil {
-		return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetOSShell(i.GetData().EnvShell), utils.GetOSShellArgs(*i.GetData().CheckHasUpdate)...)
+func (i *AptInstaller) CheckNeedsUpdate() (bool, error) {
+	if i.HasCustomUpdateCheck() {
+		return i.RunCustomUpdateCheck()
 	}
-	err := utils.RunCmdPassThrough(i.Info.Environ(), "apk", "update")
+	err := i.RunCmdPassThrough("apk", "update")
 	if err != nil {
-		return err, false
+		return false, err
 	}
-	err, success := utils.RunCmdGetSuccess(i.Info.Environ(), string(i.PackageManager), "--simulate", "upgrade", *i.Info.Name)
+	success, err := i.RunCmdGetSuccess(string(i.PackageManager), "--simulate", "upgrade", *i.Info.Name)
 	if err != nil {
-		return err, false
+		return false, err
 	}
-	return nil, !success
+	return !success, nil
 }
 
 // CheckIsInstalled implements IInstaller.
-func (i *AptInstaller) CheckIsInstalled() (error, bool) {
-	return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetShellWhich(), i.GetBinName())
+func (i *AptInstaller) CheckIsInstalled() (bool, error) {
+	if i.HasCustomInstallCheck() {
+		return i.RunCustomInstallCheck()
+	}
+	return i.RunCmdGetSuccess(utils.GetShellWhich(), i.GetBinName())
 }
 
 // GetData implements IInstaller.
@@ -99,6 +103,7 @@ func NewAptInstaller(cfg *appconfig.AppConfig, installer *appconfig.InstallerDat
 		packageManager = PackageManagerApk
 	}
 	i := &AptInstaller{
+		InstallerBase:  InstallerBase{Data: installer},
 		Config:         cfg,
 		Info:           installer,
 		PackageManager: packageManager,
diff --git a/installer/brew_installer.go b/installer/brew_installer.go
index 1f159a6..80823ba 100644
--- a/installer/brew_installer.go
+++ b/installer/brew_installer.go
@@ -6,6 +6,7 @@ import (
 )
 
 type BrewInstaller struct {
+	InstallerBase
 	Config *appconfig.AppConfig
 	Info   *appconfig.InstallerData
 }
@@ -20,29 +21,32 @@ func (i *BrewInstaller) Install() error {
 	if i.GetOpts().Tap != nil {
 		name = *i.GetOpts().Tap + "/" + name
 	}
-	return utils.RunCmdPassThrough(i.Info.Environ(), "brew", "install", name)
+	return i.RunCmdPassThrough("brew", "install", name)
 }
 
 // Update implements IInstaller.
 func (i *BrewInstaller) Update() error {
-	return utils.RunCmdPassThrough(i.Info.Environ(), "brew", "upgrade", *i.Info.Name)
+	return i.RunCmdPassThrough("brew", "upgrade", *i.Info.Name)
 }
 
 // CheckNeedsUpdate implements IInstaller.
-func (i *BrewInstaller) CheckNeedsUpdate() (error, bool) {
-	if i.GetData().CheckHasUpdate != nil {
-		return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetOSShell(i.GetData().EnvShell), utils.GetOSShellArgs(*i.GetData().CheckHasUpdate)...)
+func (i *BrewInstaller) CheckNeedsUpdate() (bool, error) {
+	if i.HasCustomUpdateCheck() {
+		return i.RunCustomUpdateCheck()
 	}
-	err, success := utils.RunCmdGetSuccess(i.Info.Environ(), "brew", "outdated", "--json", *i.Info.Name)
+	success, err := i.RunCmdGetSuccess("brew", "outdated", "--json", *i.Info.Name)
 	if err != nil {
-		return err, false
+		return false, err
 	}
-	return nil, !success
+	return !success, nil
 }
 
 // CheckIsInstalled implements IInstaller.
-func (i *BrewInstaller) CheckIsInstalled() (error, bool) {
-	return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetShellWhich(), i.GetBinName())
+func (i *BrewInstaller) CheckIsInstalled() (bool, error) {
+	if i.HasCustomInstallCheck() {
+		return i.RunCustomInstallCheck()
+	}
+	return i.RunCmdGetSuccess(utils.GetShellWhich(), i.GetBinName())
 }
 
 // GetData implements IInstaller.
@@ -71,8 +75,9 @@ func (i *BrewInstaller) GetBinName() string {
 
 func NewBrewInstaller(cfg *appconfig.AppConfig, installer *appconfig.InstallerData) *BrewInstaller {
 	i := &BrewInstaller{
-		Config: cfg,
-		Info:   installer,
+		InstallerBase: InstallerBase{Data: installer},
+		Config:        cfg,
+		Info:          installer,
 	}
 
 	return i
diff --git a/installer/filter.go b/installer/filter.go
index 73baeb9..94587c1 100644
--- a/installer/filter.go
+++ b/installer/filter.go
@@ -77,7 +77,7 @@ func InstallerIsEnabled(i IInstaller) (bool, error) {
 	shell := utils.GetOSShell(i.GetData().EnvShell)
 	args := utils.GetOSShellArgs(*enabledCmd)
 
-	err, success := utils.RunCmdGetSuccess(i.GetData().Environ(), shell, args...)
+	success, err := utils.RunCmdGetSuccess(i.GetData().Environ(), shell, args...)
 
 	if err != nil {
 		return false, err
diff --git a/installer/git_installer.go b/installer/git_installer.go
index d0a8403..341add4 100644
--- a/installer/git_installer.go
+++ b/installer/git_installer.go
@@ -11,6 +11,7 @@ import (
 )
 
 type GitInstaller struct {
+	InstallerBase
 	Config *appconfig.AppConfig
 	Info   *appconfig.InstallerData
 }
@@ -23,42 +24,45 @@ type GitOpts struct {
 // Install implements IInstaller.
 func (i *GitInstaller) Install() error {
 	args := []string{"clone", i.GetRepositoryUrl(), i.GetInstallDir()}
-	err := utils.RunCmdPassThrough(i.Info.Environ(), "git", args...)
+	err := i.RunCmdPassThrough("git", args...)
 	if err != nil {
 		return err
 	}
 	if i.GetOpts().Ref != nil {
-		return utils.RunCmdPassThrough(i.Info.Environ(), "git", "-C", i.GetInstallDir(), "checkout", *i.GetOpts().Ref)
+		return i.RunCmdPassThrough("git", "-C", i.GetInstallDir(), "checkout", *i.GetOpts().Ref)
 	}
 	return nil
 }
 
 // Update implements IInstaller.
 func (i *GitInstaller) Update() error {
-	return utils.RunCmdPassThrough(i.Info.Environ(), "git", "-C", i.GetInstallDir(), "pull")
+	return i.RunCmdPassThrough("git", "-C", i.GetInstallDir(), "pull")
 }
 
 // CheckNeedsUpdate implements IInstaller.
-func (i *GitInstaller) CheckNeedsUpdate() (error, bool) {
-	if i.GetData().CheckHasUpdate != nil {
-		return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetOSShell(i.GetData().EnvShell), utils.GetOSShellArgs(*i.GetData().CheckHasUpdate)...)
+func (i *GitInstaller) CheckNeedsUpdate() (bool, error) {
+	if i.HasCustomUpdateCheck() {
+		return i.RunCustomUpdateCheck()
 	}
-	err, _ := utils.RunCmdGetSuccess(i.Info.Environ(), "git", "-C", i.GetInstallDir(), "fetch")
+	_, err := i.RunCmdGetSuccess("git", "-C", i.GetInstallDir(), "fetch")
 	if err != nil {
-		return err, false
+		return false, err
 	}
-	output, err := utils.RunCmdGetOutput(i.Info.Environ(), "git", "-C", i.GetInstallDir(), "status", "-uno")
+	output, err := i.RunCmdGetOutput("git", "-C", i.GetInstallDir(), "status", "-uno")
 	if err != nil {
-		return err, false
+		return false, err
 	}
 	if strings.Contains(string(output), "Your branch is behind") {
-		return nil, true
+		return true, nil
 	}
-	return nil, false
+	return false, nil
 }
 
 // CheckIsInstalled implements IInstaller.
-func (i *GitInstaller) CheckIsInstalled() (error, bool) {
+func (i *GitInstaller) CheckIsInstalled() (bool, error) {
+	if i.HasCustomInstallCheck() {
+		return i.RunCustomInstallCheck()
+	}
 	return utils.PathExists(i.GetInstallDir())
 }
 
@@ -108,8 +112,9 @@ func (i *GitInstaller) GetInstallDir() string {
 
 func NewGitInstaller(cfg *appconfig.AppConfig, installer *appconfig.InstallerData) *GitInstaller {
 	i := &GitInstaller{
-		Config: cfg,
-		Info:   installer,
+		InstallerBase: InstallerBase{Data: installer},
+		Config:        cfg,
+		Info:          installer,
 	}
 
 	return i
diff --git a/installer/group_installer.go b/installer/group_installer.go
index a2714cb..2eb6ded 100644
--- a/installer/group_installer.go
+++ b/installer/group_installer.go
@@ -7,6 +7,7 @@ import (
 )
 
 type GroupInstaller struct {
+	InstallerBase
 	Config *appconfig.AppConfig
 	Data   *appconfig.InstallerData
 }
@@ -21,7 +22,7 @@ func (i *GroupInstaller) Install() error {
 	name := *info.Name
 	logger.Debug("Installing group %s", name)
 	for _, step := range *i.Data.Steps {
-		err, installer := GetInstaller(i.Config, &step)
+		installer, err := GetInstaller(i.Config, &step)
 		if err != nil {
 			return err
 		}
@@ -40,19 +41,19 @@ func (i *GroupInstaller) Update() error {
 }
 
 // CheckNeedsUpdate implements IInstaller.
-func (i *GroupInstaller) CheckNeedsUpdate() (error, bool) {
-	if i.GetData().CheckHasUpdate != nil {
-		return utils.RunCmdGetSuccess(i.Data.Environ(), utils.GetOSShell(i.GetData().EnvShell), utils.GetOSShellArgs(*i.GetData().CheckHasUpdate)...)
+func (i *GroupInstaller) CheckNeedsUpdate() (bool, error) {
+	if i.HasCustomUpdateCheck() {
+		return i.RunCustomUpdateCheck()
 	}
-	return nil, true
+	return true, nil
 }
 
 // CheckIsInstalled implements IInstaller.
-func (i *GroupInstaller) CheckIsInstalled() (error, bool) {
-	if i.GetData().CheckInstalled != nil {
-		return utils.RunCmdGetSuccess(i.Data.Environ(), utils.GetOSShell(i.GetData().EnvShell), utils.GetOSShellArgs(*i.GetData().CheckInstalled)...)
+func (i *GroupInstaller) CheckIsInstalled() (bool, error) {
+	if i.HasCustomInstallCheck() {
+		return i.RunCustomInstallCheck()
 	}
-	return utils.RunCmdGetSuccess(i.Data.Environ(), utils.GetShellWhich(), i.GetBinName())
+	return i.RunCmdGetSuccess(utils.GetShellWhich(), i.GetBinName())
 }
 
 // GetData implements IInstaller.
@@ -79,7 +80,8 @@ func (i *GroupInstaller) GetBinName() string {
 
 func NewGroupInstaller(cfg *appconfig.AppConfig, installer *appconfig.InstallerData) *GroupInstaller {
 	return &GroupInstaller{
-		Config: cfg,
-		Data:   installer,
+		InstallerBase: InstallerBase{Data: installer},
+		Config:        cfg,
+		Data:          installer,
 	}
 }
diff --git a/installer/installer.go b/installer/installer.go
index ed8bec6..7f46257 100644
--- a/installer/installer.go
+++ b/installer/installer.go
@@ -9,37 +9,84 @@ import (
 
 type IInstaller interface {
 	GetData() *appconfig.InstallerData
-	CheckIsInstalled() (error, bool)
-	CheckNeedsUpdate() (error, bool)
+	CheckIsInstalled() (bool, error)
+	CheckNeedsUpdate() (bool, error)
 	Install() error
 	Update() error
 }
 
-func GetInstaller(config *appconfig.AppConfig, data *appconfig.InstallerData) (error, IInstaller) {
+type InstallerBase struct {
+	Data *appconfig.InstallerData
+}
+
+func GetInstaller(config *appconfig.AppConfig, data *appconfig.InstallerData) (IInstaller, error) {
 	data = InstallerWithDefaults(data, data.Type, config.Defaults)
 	switch data.Type {
 	case appconfig.InstallerTypeGroup:
-		return nil, NewGroupInstaller(config, data)
+		return NewGroupInstaller(config, data), nil
 	case appconfig.InstallerTypeBrew:
-		return nil, NewBrewInstaller(config, data)
+		return NewBrewInstaller(config, data), nil
 	case appconfig.InstallerTypeShell:
-		return nil, NewShellInstaller(config, data)
+		return NewShellInstaller(config, data), nil
 	case appconfig.InstallerTypeRsync:
-		return nil, NewRsyncInstaller(config, data)
+		return NewRsyncInstaller(config, data), nil
 	case appconfig.InstallerTypeNpm, appconfig.InstallerTypePnpm, appconfig.InstallerTypeYarn:
-		return nil, NewNpmInstaller(config, data)
+		return NewNpmInstaller(config, data), nil
 	case appconfig.InstallerTypeApt, appconfig.InstallerTypeApk:
-		return nil, NewAptInstaller(config, data)
+		return NewAptInstaller(config, data), nil
 	case appconfig.InstallerTypePipx:
-		return nil, NewPipxInstaller(config, data)
+		return NewPipxInstaller(config, data), nil
 	case appconfig.InstallerTypeGit:
-		return nil, NewGitInstaller(config, data)
+		return NewGitInstaller(config, data), nil
 	case appconfig.InstallerTypeManifest:
-		return nil, NewManifestInstaller(config, data)
+		return NewManifestInstaller(config, data), nil
 	}
 	return nil, nil
 }
 
+func (i *InstallerBase) GetData() *appconfig.InstallerData {
+	return i.Data
+}
+
+func (i *InstallerBase) RunCustomUpdateCheck() (bool, error) {
+	envShell := utils.GetOSShell(i.GetData().EnvShell)
+	args := utils.GetOSShellArgs(*i.GetData().CheckHasUpdate)
+	return utils.RunCmdGetSuccess(i.Data.Environ(), envShell, args...)
+}
+
+func (i *InstallerBase) RunCustomInstallCheck() (bool, error) {
+	envShell := utils.GetOSShell(i.GetData().EnvShell)
+	args := utils.GetOSShellArgs(*i.GetData().CheckInstalled)
+	return utils.RunCmdGetSuccess(i.Data.Environ(), envShell, args...)
+}
+
+func (i *InstallerBase) HasCustomUpdateCheck() bool {
+	return i.GetData().CheckHasUpdate != nil
+}
+
+func (i *InstallerBase) HasCustomInstallCheck() bool {
+	return i.GetData().CheckInstalled != nil
+}
+
+func (i *InstallerBase) RunCmdAsFile(command string) error {
+	data := i.GetData()
+	return utils.RunCmdAsFile(data.Environ(), command, data.EnvShell)
+}
+
+func (i *InstallerBase) RunCmdPassThrough(command string, args ...string) error {
+	data := i.GetData()
+	return utils.RunCmdPassThrough(data.Environ(), command, args...)
+}
+
+func (i *InstallerBase) RunCmdGetSuccess(command string, args ...string) (bool, error) {
+	data := i.GetData()
+	return utils.RunCmdGetSuccess(data.Environ(), command, args...)
+}
+func (i *InstallerBase) RunCmdGetOutput(command string, args ...string) ([]byte, error) {
+	data := i.GetData()
+	return utils.RunCmdGetOutput(data.Environ(), command, args...)
+}
+
 func RunInstaller(config *appconfig.AppConfig, installer IInstaller) error {
 	info := installer.GetData()
 	name := *info.Name
@@ -68,7 +115,7 @@ func RunInstaller(config *appconfig.AppConfig, installer IInstaller) error {
 	}
 
 	logger.Debug("Checking %s (%s)", name, info.Type)
-	err, installed := installer.CheckIsInstalled()
+	installed, err := installer.CheckIsInstalled()
 	if err != nil {
 		return err
 	}
@@ -76,7 +123,7 @@ func RunInstaller(config *appconfig.AppConfig, installer IInstaller) error {
 		logger.Debug("%s (%s) is already installed", name, info.Type)
 		if config.CheckUpdates {
 			logger.Info("Checking updates for %s (%s)", name, info.Type)
-			err, needsUpdate := installer.CheckNeedsUpdate()
+			needsUpdate, err := installer.CheckNeedsUpdate()
 			if err != nil {
 				return err
 			}
diff --git a/installer/installer_test.go b/installer/installer_test.go
index ae9f772..292e118 100644
--- a/installer/installer_test.go
+++ b/installer/installer_test.go
@@ -22,12 +22,12 @@ func (m *MockInstaller) GetData() *appconfig.InstallerData {
 	return m.data
 }
 
-func (m *MockInstaller) CheckIsInstalled() (error, bool) {
-	return m.checkInstall, m.isInstalled
+func (m *MockInstaller) CheckIsInstalled() (bool, error) {
+	return m.isInstalled, m.checkInstall
 }
 
-func (m *MockInstaller) CheckNeedsUpdate() (error, bool) {
-	return m.checkUpdate, m.needsUpdate
+func (m *MockInstaller) CheckNeedsUpdate() (bool, error) {
+	return m.needsUpdate, m.checkUpdate
 }
 
 func (m *MockInstaller) Install() error {
@@ -42,7 +42,7 @@ func TestGetInstaller(t *testing.T) {
 	config := &appconfig.AppConfig{}
 	logger.InitLogger(config.Debug)
 	installer := &appconfig.InstallerData{Type: appconfig.InstallerTypeBrew}
-	err, inst := GetInstaller(config, installer)
+	inst, err := GetInstaller(config, installer)
 	assert.NoError(t, err)
 	assert.NotNil(t, inst)
 }
diff --git a/installer/manifest_installer.go b/installer/manifest_installer.go
index e04c25f..e88ac4d 100644
--- a/installer/manifest_installer.go
+++ b/installer/manifest_installer.go
@@ -11,6 +11,7 @@ import (
 )
 
 type ManifestInstaller struct {
+	InstallerBase
 	Config         *appconfig.AppConfig
 	Info           *appconfig.InstallerData
 	ManifestConfig *appconfig.AppConfig
@@ -35,7 +36,7 @@ func (i *ManifestInstaller) Install() error {
 	logger.Info("Installing manifest %s", name)
 	for _, step := range config.Install {
 		logger.Debug("Checking step %s", *step.Name)
-		err, installer := GetInstaller(config, &step)
+		installer, err := GetInstaller(config, &step)
 		if err != nil {
 			return err
 		}
@@ -54,21 +55,19 @@ func (i *ManifestInstaller) Update() error {
 }
 
 // CheckNeedsUpdate implements IInstaller.
-func (i *ManifestInstaller) CheckNeedsUpdate() (error, bool) {
-	info := i.GetData()
-	if info.CheckHasUpdate != nil {
-		return utils.RunCmdGetSuccess(info.Environ(), utils.GetOSShell(info.EnvShell), utils.GetOSShellArgs(*info.CheckHasUpdate)...)
+func (i *ManifestInstaller) CheckNeedsUpdate() (bool, error) {
+	if i.HasCustomUpdateCheck() {
+		return i.RunCustomUpdateCheck()
 	}
-	return nil, true
+	return true, nil
 }
 
 // CheckIsInstalled implements IInstaller.
-func (i *ManifestInstaller) CheckIsInstalled() (error, bool) {
-	info := i.GetData()
-	if info.CheckInstalled != nil {
-		return utils.RunCmdGetSuccess(info.Environ(), utils.GetOSShell(info.EnvShell), utils.GetOSShellArgs(*info.CheckInstalled)...)
+func (i *ManifestInstaller) CheckIsInstalled() (bool, error) {
+	if i.HasCustomInstallCheck() {
+		return i.RunCustomInstallCheck()
 	}
-	return nil, false
+	return false, nil
 }
 
 // GetData implements IInstaller.
@@ -128,17 +127,16 @@ func (i *ManifestInstaller) FetchManifest() error {
 
 func (i *ManifestInstaller) getGitManifestConfig(source string) (string, error) {
 	opts := i.GetOpts()
-	info := i.GetData()
 	tmpDir, err := os.MkdirTemp("", "sofmani")
 	defer os.RemoveAll(tmpDir)
 	if err != nil {
 		return "", err
 	}
 	logger.Debug("Cloning %s to %s", source, tmpDir)
-	err, success := utils.RunCmdGetSuccess(info.Environ(), "git", "clone", "--depth=1", source, tmpDir)
+	success, err := i.RunCmdGetSuccess("git", "clone", "--depth=1", source, tmpDir)
 	if opts.Ref != nil {
 		logger.Debug("Checking out ref %s", *opts.Ref)
-		err = utils.RunCmdPassThrough(info.Environ(), "git", "-C", tmpDir, "checkout", *opts.Ref)
+		err = i.RunCmdPassThrough("git", "-C", tmpDir, "checkout", *opts.Ref)
 		if err != nil {
 			return "", err
 		}
@@ -203,7 +201,8 @@ func (i *ManifestInstaller) inheritManifest(config *appconfig.AppConfig) *appcon
 
 func NewManifestInstaller(cfg *appconfig.AppConfig, installer *appconfig.InstallerData) *ManifestInstaller {
 	return &ManifestInstaller{
-		Config: cfg,
-		Info:   installer,
+		InstallerBase: InstallerBase{Data: installer},
+		Config:        cfg,
+		Info:          installer,
 	}
 }
diff --git a/installer/npm_installer.go b/installer/npm_installer.go
index d2b9690..bf93d31 100644
--- a/installer/npm_installer.go
+++ b/installer/npm_installer.go
@@ -6,6 +6,7 @@ import (
 )
 
 type NpmInstaller struct {
+	InstallerBase
 	Config         *appconfig.AppConfig
 	PackageManager PackageManager
 	Info           *appconfig.InstallerData
@@ -25,32 +26,32 @@ const (
 
 // Install implements IInstaller.
 func (i *NpmInstaller) Install() error {
-	return utils.RunCmdPassThrough(i.Info.Environ(), string(i.PackageManager), "install", "--global", *i.Info.Name)
+	return i.RunCmdPassThrough(string(i.PackageManager), "install", "--global", *i.Info.Name)
 }
 
 // Update implements IInstaller.
 func (i *NpmInstaller) Update() error {
-	return utils.RunCmdPassThrough(i.Info.Environ(), string(i.PackageManager), "install", "--global", *i.Info.Name+"@latest")
+	return i.RunCmdPassThrough(string(i.PackageManager), "install", "--global", *i.Info.Name+"@latest")
 }
 
 // CheckNeedsUpdate implements IInstaller.
-func (i *NpmInstaller) CheckNeedsUpdate() (error, bool) {
-	if i.GetData().CheckHasUpdate != nil {
-		return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetShellWhich(), utils.GetOSShellArgs(*i.GetData().CheckHasUpdate)...)
+func (i *NpmInstaller) CheckNeedsUpdate() (bool, error) {
+	if i.HasCustomUpdateCheck() {
+		return i.RunCustomUpdateCheck()
 	}
-	err, success := utils.RunCmdGetSuccess(i.Info.Environ(), string(i.PackageManager), "outdated", "--global", "--json", *i.Info.Name)
+	success, err := i.RunCmdGetSuccess(string(i.PackageManager), "outdated", "--global", "--json", *i.Info.Name)
 	if err != nil {
-		return err, false
+		return false, err
 	}
-	return nil, !success
+	return !success, nil
 }
 
 // CheckIsInstalled implements IInstaller.
-func (i *NpmInstaller) CheckIsInstalled() (error, bool) {
-	if i.GetData().CheckInstalled != nil {
-		return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetOSShell(i.GetData().EnvShell), utils.GetOSShellArgs(*i.GetData().CheckInstalled)...)
+func (i *NpmInstaller) CheckIsInstalled() (bool, error) {
+	if i.HasCustomInstallCheck() {
+		return i.RunCustomInstallCheck()
 	}
-	return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetShellWhich(), i.GetBinName())
+	return i.RunCmdGetSuccess(utils.GetShellWhich(), i.GetBinName())
 }
 
 // GetData implements IInstaller.
@@ -83,6 +84,7 @@ func NewNpmInstaller(cfg *appconfig.AppConfig, installer *appconfig.InstallerDat
 		packageManager = PackageManagerYarn
 	}
 	i := &NpmInstaller{
+		InstallerBase:  InstallerBase{Data: installer},
 		Config:         cfg,
 		PackageManager: packageManager,
 		Info:           installer,
diff --git a/installer/pipx_installer.go b/installer/pipx_installer.go
index a4622b4..18711de 100644
--- a/installer/pipx_installer.go
+++ b/installer/pipx_installer.go
@@ -6,6 +6,7 @@ import (
 )
 
 type PipxInstaller struct {
+	InstallerBase
 	Config *appconfig.AppConfig
 	Info   *appconfig.InstallerData
 }
@@ -17,29 +18,32 @@ type PipxOpts struct {
 // Install implements IInstaller.
 func (i *PipxInstaller) Install() error {
 	name := *i.Info.Name
-	return utils.RunCmdPassThrough(i.Info.Environ(), "pipx", "install", name)
+	return i.RunCmdPassThrough("pipx", "install", name)
 }
 
 // Update implements IInstaller.
 func (i *PipxInstaller) Update() error {
-	return utils.RunCmdPassThrough(i.Info.Environ(), "pipx", "upgrade", *i.Info.Name)
+	return i.RunCmdPassThrough("pipx", "upgrade", *i.Info.Name)
 }
 
 // CheckNeedsUpdate implements IInstaller.
-func (i *PipxInstaller) CheckNeedsUpdate() (error, bool) {
-	if i.GetData().CheckHasUpdate != nil {
-		return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetOSShell(i.GetData().EnvShell), utils.GetOSShellArgs(*i.GetData().CheckHasUpdate)...)
+func (i *PipxInstaller) CheckNeedsUpdate() (bool, error) {
+	if i.HasCustomUpdateCheck() {
+		return i.RunCustomUpdateCheck()
 	}
-	err, success := utils.RunCmdGetSuccess(i.Info.Environ(), "pipx", "upgrade", "--pip-args=--dry-run", *i.Info.Name)
+	success, err := i.RunCmdGetSuccess("pipx", "upgrade", "--pip-args=--dry-run", *i.Info.Name)
 	if err != nil {
-		return err, false
+		return false, err
 	}
-	return nil, !success
+	return !success, nil
 }
 
 // CheckIsInstalled implements IInstaller.
-func (i *PipxInstaller) CheckIsInstalled() (error, bool) {
-	return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetShellWhich(), i.GetBinName())
+func (i *PipxInstaller) CheckIsInstalled() (bool, error) {
+	if i.HasCustomInstallCheck() {
+		return i.RunCustomInstallCheck()
+	}
+	return i.RunCmdGetSuccess(utils.GetShellWhich(), i.GetBinName())
 }
 
 // GetData implements IInstaller.
@@ -66,8 +70,9 @@ func (i *PipxInstaller) GetBinName() string {
 
 func NewPipxInstaller(cfg *appconfig.AppConfig, installer *appconfig.InstallerData) *PipxInstaller {
 	i := &PipxInstaller{
-		Config: cfg,
-		Info:   installer,
+		InstallerBase: InstallerBase{Data: installer},
+		Config:        cfg,
+		Info:          installer,
 	}
 
 	return i
diff --git a/installer/rsync_installer.go b/installer/rsync_installer.go
index 7330a2a..a1d5ef3 100644
--- a/installer/rsync_installer.go
+++ b/installer/rsync_installer.go
@@ -9,6 +9,7 @@ import (
 )
 
 type RsyncInstaller struct {
+	InstallerBase
 	Config *appconfig.AppConfig
 	Info   *appconfig.InstallerData
 }
@@ -31,15 +32,16 @@ func (i *RsyncInstaller) Install() error {
 			flags = append(flags, flag)
 		}
 	}
-
-	src := utils.GetRealPath(i.Info.Environ(), *i.GetOpts().Source)
-	dest := utils.GetRealPath(i.Info.Environ(), *i.GetOpts().Destination)
+	data := i.GetData()
+	env := data.Environ()
+	src := utils.GetRealPath(env, *i.GetOpts().Source)
+	dest := utils.GetRealPath(env, *i.GetOpts().Destination)
 
 	flags = append(flags, src)
 	flags = append(flags, dest)
 
 	logger.Debug("rsync %s to %s", src, dest)
-	return utils.RunCmdPassThrough(i.Info.Environ(), "rsync", flags...)
+	return i.RunCmdPassThrough("rsync", flags...)
 }
 
 // Update implements IInstaller.
@@ -48,19 +50,19 @@ func (i *RsyncInstaller) Update() error {
 }
 
 // CheckNeedsUpdate implements IInstaller.
-func (i *RsyncInstaller) CheckNeedsUpdate() (error, bool) {
-	if i.GetData().CheckHasUpdate != nil {
-		return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetOSShell(i.GetData().EnvShell), utils.GetOSShellArgs(*i.GetData().CheckHasUpdate)...)
+func (i *RsyncInstaller) CheckNeedsUpdate() (bool, error) {
+	if i.HasCustomUpdateCheck() {
+		return i.RunCustomUpdateCheck()
 	}
-	return nil, true
+	return true, nil
 }
 
 // CheckIsInstalled implements IInstaller.
-func (i *RsyncInstaller) CheckIsInstalled() (error, bool) {
-	if i.GetData().CheckInstalled != nil {
-		return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetOSShell(i.GetData().EnvShell), utils.GetOSShellArgs(*i.GetData().CheckInstalled)...)
+func (i *RsyncInstaller) CheckIsInstalled() (bool, error) {
+	if i.HasCustomInstallCheck() {
+		return i.RunCustomInstallCheck()
 	}
-	return nil, false
+	return false, nil
 }
 
 // GetData implements IInstaller.
@@ -95,8 +97,9 @@ func (i *RsyncInstaller) GetBinName() string {
 
 func NewRsyncInstaller(cfg *appconfig.AppConfig, installer *appconfig.InstallerData) *RsyncInstaller {
 	i := &RsyncInstaller{
-		Config: cfg,
-		Info:   installer,
+		InstallerBase: InstallerBase{Data: installer},
+		Config:        cfg,
+		Info:          installer,
 	}
 
 	return i
diff --git a/installer/shell_installer.go b/installer/shell_installer.go
index 787672c..86ac1dd 100644
--- a/installer/shell_installer.go
+++ b/installer/shell_installer.go
@@ -6,6 +6,7 @@ import (
 )
 
 type ShellInstaller struct {
+	InstallerBase
 	Config *appconfig.AppConfig
 	Info   *appconfig.InstallerData
 }
@@ -17,35 +18,31 @@ type ShellOpts struct {
 
 // Install implements IInstaller.
 func (i *ShellInstaller) Install() error {
-	return utils.RunCmdAsFile(i.Info.Environ(), *i.GetOpts().Command, i.GetData().EnvShell)
+	return i.RunCmdAsFile(*i.GetOpts().Command)
 }
 
 // Update implements IInstaller.
 func (i *ShellInstaller) Update() error {
 	if i.GetOpts().UpdateCommand != nil {
-		return utils.RunCmdAsFile(i.Info.Environ(), *i.GetOpts().UpdateCommand, i.GetData().EnvShell)
+		return i.RunCmdAsFile(*i.GetOpts().UpdateCommand)
 	}
 	return i.Install()
 }
 
 // CheckNeedsUpdate implements IInstaller.
-func (i *ShellInstaller) CheckNeedsUpdate() (error, bool) {
-	if i.GetData().CheckHasUpdate != nil {
-		shell := utils.GetOSShell(i.GetData().EnvShell)
-		args := utils.GetOSShellArgs(*i.GetData().CheckHasUpdate)
-		return utils.RunCmdGetSuccess(i.Info.Environ(), shell, args...)
+func (i *ShellInstaller) CheckNeedsUpdate() (bool, error) {
+	if i.HasCustomUpdateCheck() {
+		return i.RunCustomUpdateCheck()
 	}
-	return nil, false
+	return false, nil
 }
 
 // CheckIsInstalled implements IInstaller.
-func (i *ShellInstaller) CheckIsInstalled() (error, bool) {
-	if i.GetData().CheckInstalled != nil {
-		shell := utils.GetOSShell(i.GetData().EnvShell)
-		args := utils.GetOSShellArgs(*i.GetData().CheckInstalled)
-		return utils.RunCmdGetSuccess(i.Info.Environ(), shell, args...)
+func (i *ShellInstaller) CheckIsInstalled() (bool, error) {
+	if i.HasCustomInstallCheck() {
+		return i.RunCustomInstallCheck()
 	}
-	return utils.RunCmdGetSuccess(i.Info.Environ(), utils.GetShellWhich(), i.GetBinName())
+	return i.RunCmdGetSuccess(utils.GetShellWhich(), i.GetBinName())
 }
 
 // GetData implements IInstaller.
@@ -77,7 +74,8 @@ func (i *ShellInstaller) GetBinName() string {
 
 func NewShellInstaller(cfg *appconfig.AppConfig, installer *appconfig.InstallerData) *ShellInstaller {
 	return &ShellInstaller{
-		Config: cfg,
-		Info:   installer,
+		InstallerBase: InstallerBase{Data: installer},
+		Config:        cfg,
+		Info:          installer,
 	}
 }
diff --git a/main.go b/main.go
index c8c5335..f7b9348 100644
--- a/main.go
+++ b/main.go
@@ -32,7 +32,7 @@ func main() {
 
 	logger.Info("Checking all installers...")
 	for _, i := range cfg.Install {
-		err, installerInstance := installer.GetInstaller(cfg, &i)
+		installerInstance, err := installer.GetInstaller(cfg, &i)
 		if err != nil {
 			logger.Error("%s", err)
 			return
diff --git a/utils/command.go b/utils/command.go
index 6f4486a..7f7daac 100644
--- a/utils/command.go
+++ b/utils/command.go
@@ -41,15 +41,15 @@ func RunCmdPassThroughChained(env []string, commands [][]string) error {
 	return nil
 }
 
-func RunCmdGetSuccess(env []string, bin string, args ...string) (error, bool) {
+func RunCmdGetSuccess(env []string, bin string, args ...string) (bool, error) {
 	logger.Debug("Running command: %s %v", bin, args)
 	cmd := exec.Command(bin, args...)
 	cmd.Env = ResolveEnvPaths(os.Environ(), cmd.Env, env)
 	err := cmd.Run()
 	if err != nil {
-		return nil, false
+		return false, nil
 	}
-	return nil, true
+	return true, nil
 }
 
 func RunCmdGetOutput(env []string, bin string, args ...string) ([]byte, error) {
diff --git a/utils/fs.go b/utils/fs.go
index 0c5cd94..e53a42a 100644
--- a/utils/fs.go
+++ b/utils/fs.go
@@ -33,8 +33,8 @@ func GetRealPath(env []string, path string) string {
 	return strings.TrimSpace(string(path))
 }
 
-func PathExists(path string) (error, bool) {
+func PathExists(path string) (bool, error) {
 	_, err := os.Stat(path)
 	exists := !errors.Is(err, fs.ErrNotExist)
-	return nil, exists
+	return exists, nil
 }