diff --git a/internal/cmd/pkgcmd/cmd_install.go b/internal/cmd/pkgcmd/cmd_install.go
index 08bf87c9..d3d0bf55 100644
--- a/internal/cmd/pkgcmd/cmd_install.go
+++ b/internal/cmd/pkgcmd/cmd_install.go
@@ -9,6 +9,7 @@ import (
 	"strings"
 
 	"github.com/host-uk/core/pkg/i18n"
+	coreio "github.com/host-uk/core/pkg/io"
 	"github.com/host-uk/core/pkg/repos"
 	"github.com/spf13/cobra"
 )
@@ -73,12 +74,12 @@ func runPkgInstall(repoArg, targetDir string, addToRegistry bool) error {
 
 	repoPath := filepath.Join(targetDir, repoName)
 
-	if _, err := os.Stat(filepath.Join(repoPath, ".git")); err == nil {
+	if _, err := coreio.Local.List(filepath.Join(repoPath, ".git")); err == nil {
 		fmt.Printf("%s %s\n", dimStyle.Render(i18n.Label("skip")), i18n.T("cmd.pkg.install.already_exists", map[string]string{"Name": repoName, "Path": repoPath}))
 		return nil
 	}
 
-	if err := os.MkdirAll(targetDir, 0755); err != nil {
+	if err := coreio.Local.EnsureDir(targetDir); err != nil {
 		return fmt.Errorf("%s: %w", i18n.T("i18n.fail.create", "directory"), err)
 	}
 
@@ -123,18 +124,17 @@ func addToRegistryFile(org, repoName string) error {
 		return nil
 	}
 
-	f, err := os.OpenFile(regPath, os.O_APPEND|os.O_WRONLY, 0644)
+	content, err := coreio.Local.Read(regPath)
 	if err != nil {
 		return err
 	}
-	defer f.Close()
 
 	repoType := detectRepoType(repoName)
 	entry := fmt.Sprintf("\n  %s:\n    type: %s\n    description: (installed via core pkg install)\n",
 		repoName, repoType)
 
-	_, err = f.WriteString(entry)
-	return err
+	content += entry
+	return coreio.Local.Write(regPath, content)
 }
 
 func detectRepoType(name string) string {
diff --git a/internal/cmd/pkgcmd/cmd_manage.go b/internal/cmd/pkgcmd/cmd_manage.go
index d7f1bb95..cabba86f 100644
--- a/internal/cmd/pkgcmd/cmd_manage.go
+++ b/internal/cmd/pkgcmd/cmd_manage.go
@@ -3,12 +3,12 @@ package pkgcmd
 import (
 	"errors"
 	"fmt"
-	"os"
 	"os/exec"
 	"path/filepath"
 	"strings"
 
 	"github.com/host-uk/core/pkg/i18n"
+	coreio "github.com/host-uk/core/pkg/io"
 	"github.com/host-uk/core/pkg/repos"
 	"github.com/spf13/cobra"
 )
@@ -58,7 +58,7 @@ func runPkgList() error {
 	for _, r := range allRepos {
 		repoPath := filepath.Join(basePath, r.Name)
 		exists := false
-		if _, err := os.Stat(filepath.Join(repoPath, ".git")); err == nil {
+		if _, err := coreio.Local.List(filepath.Join(repoPath, ".git")); err == nil {
 			exists = true
 			installed++
 		} else {
@@ -147,7 +147,7 @@ func runPkgUpdate(packages []string, all bool) error {
 	for _, name := range toUpdate {
 		repoPath := filepath.Join(basePath, name)
 
-		if _, err := os.Stat(filepath.Join(repoPath, ".git")); os.IsNotExist(err) {
+		if _, err := coreio.Local.List(filepath.Join(repoPath, ".git")); err != nil {
 			fmt.Printf("  %s %s (%s)\n", dimStyle.Render("○"), name, i18n.T("cmd.pkg.update.not_installed"))
 			skipped++
 			continue
@@ -219,7 +219,7 @@ func runPkgOutdated() error {
 	for _, r := range reg.List() {
 		repoPath := filepath.Join(basePath, r.Name)
 
-		if _, err := os.Stat(filepath.Join(repoPath, ".git")); os.IsNotExist(err) {
+		if _, err := coreio.Local.List(filepath.Join(repoPath, ".git")); err != nil {
 			notInstalled++
 			continue
 		}
diff --git a/internal/cmd/sdk/detect.go b/internal/cmd/sdk/detect.go
index aeb221f1..a835ab88 100644
--- a/internal/cmd/sdk/detect.go
+++ b/internal/cmd/sdk/detect.go
@@ -2,9 +2,10 @@ package sdk
 
 import (
 	"fmt"
-	"os"
 	"path/filepath"
 	"strings"
+
+	coreio "github.com/host-uk/core/pkg/io"
 )
 
 // commonSpecPaths are checked in order when no spec is configured.
@@ -25,7 +26,7 @@ func (s *SDK) DetectSpec() (string, error) {
 	// 1. Check configured path
 	if s.config.Spec != "" {
 		specPath := filepath.Join(s.projectDir, s.config.Spec)
-		if _, err := os.Stat(specPath); err == nil {
+		if coreio.Local.IsFile(specPath) {
 			return specPath, nil
 		}
 		return "", fmt.Errorf("sdk.DetectSpec: configured spec not found: %s", s.config.Spec)
@@ -34,7 +35,7 @@ func (s *SDK) DetectSpec() (string, error) {
 	// 2. Check common paths
 	for _, p := range commonSpecPaths {
 		specPath := filepath.Join(s.projectDir, p)
-		if _, err := os.Stat(specPath); err == nil {
+		if coreio.Local.IsFile(specPath) {
 			return specPath, nil
 		}
 	}
@@ -51,12 +52,12 @@ func (s *SDK) DetectSpec() (string, error) {
 // detectScramble checks for Laravel Scramble and exports the spec.
 func (s *SDK) detectScramble() (string, error) {
 	composerPath := filepath.Join(s.projectDir, "composer.json")
-	if _, err := os.Stat(composerPath); err != nil {
+	if !coreio.Local.IsFile(composerPath) {
 		return "", fmt.Errorf("no composer.json")
 	}
 
 	// Check for scramble in composer.json
-	data, err := os.ReadFile(composerPath)
+	data, err := coreio.Local.Read(composerPath)
 	if err != nil {
 		return "", err
 	}
@@ -71,8 +72,7 @@ func (s *SDK) detectScramble() (string, error) {
 }
 
 // containsScramble checks if composer.json includes scramble.
-func containsScramble(data []byte) bool {
-	content := string(data)
+func containsScramble(content string) bool {
 	return strings.Contains(content, "dedoc/scramble") ||
 		strings.Contains(content, "\"scramble\"")
 }
diff --git a/internal/cmd/sdk/detect_test.go b/internal/cmd/sdk/detect_test.go
index 4511e08f..fef2dbcb 100644
--- a/internal/cmd/sdk/detect_test.go
+++ b/internal/cmd/sdk/detect_test.go
@@ -62,7 +62,7 @@ func TestContainsScramble(t *testing.T) {
 	}
 
 	for _, tt := range tests {
-		assert.Equal(t, tt.expected, containsScramble([]byte(tt.data)))
+		assert.Equal(t, tt.expected, containsScramble(tt.data))
 	}
 }
 
diff --git a/internal/cmd/sdk/generators/go.go b/internal/cmd/sdk/generators/go.go
index e2c2bc16..0aff5279 100644
--- a/internal/cmd/sdk/generators/go.go
+++ b/internal/cmd/sdk/generators/go.go
@@ -6,6 +6,8 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+
+	coreio "github.com/host-uk/core/pkg/io"
 )
 
 // GoGenerator generates Go SDKs from OpenAPI specs.
@@ -34,7 +36,7 @@ func (g *GoGenerator) Install() string {
 
 // Generate creates SDK from OpenAPI spec.
 func (g *GoGenerator) Generate(ctx context.Context, opts Options) error {
-	if err := os.MkdirAll(opts.OutputDir, 0755); err != nil {
+	if err := coreio.Local.EnsureDir(opts.OutputDir); err != nil {
 		return fmt.Errorf("go.Generate: failed to create output dir: %w", err)
 	}
 
@@ -61,7 +63,7 @@ func (g *GoGenerator) generateNative(ctx context.Context, opts Options) error {
 	}
 
 	goMod := fmt.Sprintf("module %s\n\ngo 1.21\n", opts.PackageName)
-	return os.WriteFile(filepath.Join(opts.OutputDir, "go.mod"), []byte(goMod), 0644)
+	return coreio.Local.Write(filepath.Join(opts.OutputDir, "go.mod"), goMod)
 }
 
 func (g *GoGenerator) generateDocker(ctx context.Context, opts Options) error {
diff --git a/internal/cmd/sdk/generators/php.go b/internal/cmd/sdk/generators/php.go
index 6403af37..ce701916 100644
--- a/internal/cmd/sdk/generators/php.go
+++ b/internal/cmd/sdk/generators/php.go
@@ -6,6 +6,8 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+
+	coreio "github.com/host-uk/core/pkg/io"
 )
 
 // PHPGenerator generates PHP SDKs from OpenAPI specs.
@@ -38,7 +40,7 @@ func (g *PHPGenerator) Generate(ctx context.Context, opts Options) error {
 		return fmt.Errorf("php.Generate: Docker is required but not available")
 	}
 
-	if err := os.MkdirAll(opts.OutputDir, 0755); err != nil {
+	if err := coreio.Local.EnsureDir(opts.OutputDir); err != nil {
 		return fmt.Errorf("php.Generate: failed to create output dir: %w", err)
 	}
 
diff --git a/internal/cmd/sdk/generators/python.go b/internal/cmd/sdk/generators/python.go
index bd5f91f0..a95bcb6d 100644
--- a/internal/cmd/sdk/generators/python.go
+++ b/internal/cmd/sdk/generators/python.go
@@ -6,6 +6,8 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+
+	coreio "github.com/host-uk/core/pkg/io"
 )
 
 // PythonGenerator generates Python SDKs from OpenAPI specs.
@@ -34,7 +36,7 @@ func (g *PythonGenerator) Install() string {
 
 // Generate creates SDK from OpenAPI spec.
 func (g *PythonGenerator) Generate(ctx context.Context, opts Options) error {
-	if err := os.MkdirAll(opts.OutputDir, 0755); err != nil {
+	if err := coreio.Local.EnsureDir(opts.OutputDir); err != nil {
 		return fmt.Errorf("python.Generate: failed to create output dir: %w", err)
 	}
 
diff --git a/internal/cmd/sdk/generators/typescript.go b/internal/cmd/sdk/generators/typescript.go
index c88b9b6e..843a146b 100644
--- a/internal/cmd/sdk/generators/typescript.go
+++ b/internal/cmd/sdk/generators/typescript.go
@@ -6,6 +6,8 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+
+	coreio "github.com/host-uk/core/pkg/io"
 )
 
 // TypeScriptGenerator generates TypeScript SDKs from OpenAPI specs.
@@ -38,7 +40,7 @@ func (g *TypeScriptGenerator) Install() string {
 
 // Generate creates SDK from OpenAPI spec.
 func (g *TypeScriptGenerator) Generate(ctx context.Context, opts Options) error {
-	if err := os.MkdirAll(opts.OutputDir, 0755); err != nil {
+	if err := coreio.Local.EnsureDir(opts.OutputDir); err != nil {
 		return fmt.Errorf("typescript.Generate: failed to create output dir: %w", err)
 	}
 
diff --git a/internal/cmd/workspace/config.go b/internal/cmd/workspace/config.go
index fc781b5b..2be8e35f 100644
--- a/internal/cmd/workspace/config.go
+++ b/internal/cmd/workspace/config.go
@@ -5,6 +5,7 @@ import (
 	"os"
 	"path/filepath"
 
+	coreio "github.com/host-uk/core/pkg/io"
 	"gopkg.in/yaml.v3"
 )
 
@@ -28,9 +29,14 @@ func DefaultConfig() *WorkspaceConfig {
 // Returns nil if no config file exists (caller should check for nil).
 func LoadConfig(dir string) (*WorkspaceConfig, error) {
 	path := filepath.Join(dir, ".core", "workspace.yaml")
-	data, err := os.ReadFile(path)
+	data, err := coreio.Local.Read(path)
 	if err != nil {
-		if os.IsNotExist(err) {
+		// If using Local.Read, it returns error on not found.
+		// We can check if file exists first or handle specific error if exposed.
+		// Simplest is to check existence first or assume IsNotExist.
+		// Since we don't have easy IsNotExist check on coreio error returned yet (uses wrapped error),
+		// let's check IsFile first.
+		if !coreio.Local.IsFile(path) {
 			// Try parent directory
 			parent := filepath.Dir(dir)
 			if parent != dir {
@@ -43,7 +49,7 @@ func LoadConfig(dir string) (*WorkspaceConfig, error) {
 	}
 
 	config := DefaultConfig()
-	if err := yaml.Unmarshal(data, config); err != nil {
+	if err := yaml.Unmarshal([]byte(data), config); err != nil {
 		return nil, fmt.Errorf("failed to parse workspace config: %w", err)
 	}
 
@@ -57,7 +63,7 @@ func LoadConfig(dir string) (*WorkspaceConfig, error) {
 // SaveConfig saves the configuration to the given directory's .core/workspace.yaml.
 func SaveConfig(dir string, config *WorkspaceConfig) error {
 	coreDir := filepath.Join(dir, ".core")
-	if err := os.MkdirAll(coreDir, 0755); err != nil {
+	if err := coreio.Local.EnsureDir(coreDir); err != nil {
 		return fmt.Errorf("failed to create .core directory: %w", err)
 	}
 
@@ -67,7 +73,7 @@ func SaveConfig(dir string, config *WorkspaceConfig) error {
 		return fmt.Errorf("failed to marshal workspace config: %w", err)
 	}
 
-	if err := os.WriteFile(path, data, 0644); err != nil {
+	if err := coreio.Local.Write(path, string(data)); err != nil {
 		return fmt.Errorf("failed to write workspace config: %w", err)
 	}
 
@@ -82,7 +88,7 @@ func FindWorkspaceRoot() (string, error) {
 	}
 
 	for {
-		if _, err := os.Stat(filepath.Join(dir, ".core", "workspace.yaml")); err == nil {
+		if coreio.Local.IsFile(filepath.Join(dir, ".core", "workspace.yaml")) {
 			return dir, nil
 		}