diff --git a/internal/cmd/dev/cmd_file_sync.go b/internal/cmd/dev/cmd_file_sync.go
index 9eb44fb..736c1c4 100644
--- a/internal/cmd/dev/cmd_file_sync.go
+++ b/internal/cmd/dev/cmd_file_sync.go
@@ -9,7 +9,6 @@ package dev
 
 import (
 	"context"
-	"os"
 	"os/exec"
 	"path/filepath"
 	"strings"
@@ -62,25 +61,14 @@ func runFileSync(source string) error {
 		return log.E("dev.sync", "path traversal not allowed", nil)
 	}
 
-	// Validate source exists
-	sourceInfo, err := os.Stat(source) // Keep os.Stat for local source check or use coreio? coreio.Local.IsFile is bool.
-	// If source is local file on disk (not in medium), we can use os.Stat.
-	// But concept is everything is via Medium?
-	// User is running CLI on host. `source` is relative to CWD.
-	// coreio.Local uses absolute path or relative to root (which is "/" by default).
-	// So coreio.Local works.
-	if !coreio.Local.IsFile(source) {
-		// Might be directory
-		// IsFile returns false for directory.
+	// Convert to absolute path for io.Local
+	absSource, err := filepath.Abs(source)
+	if err != nil {
+		return log.E("dev.sync", "failed to resolve source path", err)
 	}
-	// Let's rely on os.Stat for initial source check to distinguish dir vs file easily if coreio doesn't expose Stat.
-	// coreio doesn't expose Stat.
-
-	// Check using standard os for source determination as we are outside strict sandbox for input args potentially?
-	// But we should use coreio where possible.
-	// coreio.Local.List worked for dirs.
-	// Let's stick to os.Stat for source properties finding as typically allowed for CLI args.
 
+	// Validate source exists using io.Local.Stat
+	sourceInfo, err := coreio.Local.Stat(absSource)
 	if err != nil {
 		return log.E("dev.sync", i18n.T("cmd.dev.file_sync.error.source_not_found", map[string]interface{}{"Path": source}), err)
 	}
diff --git a/internal/cmd/dev/cmd_workflow_test.go b/internal/cmd/dev/cmd_workflow_test.go
index 3f0cd82..d4cf4ed 100644
--- a/internal/cmd/dev/cmd_workflow_test.go
+++ b/internal/cmd/dev/cmd_workflow_test.go
@@ -1,28 +1,29 @@
 package dev
 
 import (
-	"os"
 	"path/filepath"
 	"testing"
+
+	"github.com/host-uk/core/pkg/io"
 )
 
 func TestFindWorkflows_Good(t *testing.T) {
 	// Create a temp directory with workflow files
 	tmpDir := t.TempDir()
 	workflowsDir := filepath.Join(tmpDir, ".github", "workflows")
-	if err := os.MkdirAll(workflowsDir, 0755); err != nil {
+	if err := io.Local.EnsureDir(workflowsDir); err != nil {
 		t.Fatalf("Failed to create workflows dir: %v", err)
 	}
 
 	// Create some workflow files
 	for _, name := range []string{"qa.yml", "tests.yml", "codeql.yaml"} {
-		if err := os.WriteFile(filepath.Join(workflowsDir, name), []byte("name: Test"), 0644); err != nil {
+		if err := io.Local.Write(filepath.Join(workflowsDir, name), "name: Test"); err != nil {
 			t.Fatalf("Failed to create workflow file: %v", err)
 		}
 	}
 
 	// Create a non-workflow file (should be ignored)
-	if err := os.WriteFile(filepath.Join(workflowsDir, "readme.md"), []byte("# Workflows"), 0644); err != nil {
+	if err := io.Local.Write(filepath.Join(workflowsDir, "readme.md"), "# Workflows"); err != nil {
 		t.Fatalf("Failed to create readme file: %v", err)
 	}
 
@@ -57,12 +58,12 @@ func TestFindWorkflows_NoWorkflowsDir(t *testing.T) {
 func TestFindTemplateWorkflow_Good(t *testing.T) {
 	tmpDir := t.TempDir()
 	templatesDir := filepath.Join(tmpDir, ".github", "workflow-templates")
-	if err := os.MkdirAll(templatesDir, 0755); err != nil {
+	if err := io.Local.EnsureDir(templatesDir); err != nil {
 		t.Fatalf("Failed to create templates dir: %v", err)
 	}
 
 	templateContent := "name: QA\non: [push]"
-	if err := os.WriteFile(filepath.Join(templatesDir, "qa.yml"), []byte(templateContent), 0644); err != nil {
+	if err := io.Local.Write(filepath.Join(templatesDir, "qa.yml"), templateContent); err != nil {
 		t.Fatalf("Failed to create template file: %v", err)
 	}
 
@@ -82,12 +83,12 @@ func TestFindTemplateWorkflow_Good(t *testing.T) {
 func TestFindTemplateWorkflow_FallbackToWorkflows(t *testing.T) {
 	tmpDir := t.TempDir()
 	workflowsDir := filepath.Join(tmpDir, ".github", "workflows")
-	if err := os.MkdirAll(workflowsDir, 0755); err != nil {
+	if err := io.Local.EnsureDir(workflowsDir); err != nil {
 		t.Fatalf("Failed to create workflows dir: %v", err)
 	}
 
 	templateContent := "name: Tests\non: [push]"
-	if err := os.WriteFile(filepath.Join(workflowsDir, "tests.yml"), []byte(templateContent), 0644); err != nil {
+	if err := io.Local.Write(filepath.Join(workflowsDir, "tests.yml"), templateContent); err != nil {
 		t.Fatalf("Failed to create workflow file: %v", err)
 	}