diff --git a/jety.go b/jety.go
index e55547f..a153faf 100644
--- a/jety.go
+++ b/jety.go
@@ -4,7 +4,6 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"maps"
 	"os"
 	"path/filepath"
 	"strings"
@@ -33,7 +32,8 @@ type (
 		configPath       string
 		configFileUsed   string
 		configType       configType
-		mapConfig        map[string]ConfigMap
+		overrideConfig   map[string]ConfigMap
+		fileConfig       map[string]ConfigMap
 		defaultConfig    map[string]ConfigMap
 		envConfig        map[string]ConfigMap
 		combinedConfig   map[string]ConfigMap
@@ -50,7 +50,8 @@ var (
 func NewConfigManager() *ConfigManager {
 	cm := ConfigManager{}
 	cm.envConfig = make(map[string]ConfigMap)
-	cm.mapConfig = make(map[string]ConfigMap)
+	cm.overrideConfig = make(map[string]ConfigMap)
+	cm.fileConfig = make(map[string]ConfigMap)
 	cm.defaultConfig = make(map[string]ConfigMap)
 	cm.combinedConfig = make(map[string]ConfigMap)
 	envSet := os.Environ()
@@ -99,13 +100,21 @@ func (c *ConfigManager) collapse() {
 	c.mutex.Lock()
 	defer c.mutex.Unlock()
 	ccm := make(map[string]ConfigMap)
+	// Precedence (highest to lowest): overrides (Set) > env > file > defaults
 	for k, v := range c.defaultConfig {
 		ccm[k] = v
-		if _, ok := c.envConfig[k]; ok {
-			ccm[k] = c.envConfig[k]
+	}
+	for k, v := range c.fileConfig {
+		ccm[k] = v
+	}
+	for k := range c.defaultConfig {
+		if v, ok := c.envConfig[k]; ok {
+			ccm[k] = v
 		}
 	}
-	maps.Copy(ccm, c.mapConfig)
+	for k, v := range c.overrideConfig {
+		ccm[k] = v
+	}
 	c.combinedConfig = ccm
 }
 
@@ -216,7 +225,7 @@ func (c *ConfigManager) ReadInConfig() error {
 		conf[lower] = ConfigMap{Key: k, Value: v}
 	}
 	c.mutex.Lock()
-	c.mapConfig = conf
+	c.fileConfig = conf
 	c.configFileUsed = configFile
 	c.mutex.Unlock()
 	c.collapse()
diff --git a/jety_test.go b/jety_test.go
index 56d9f0f..e71e0db 100644
--- a/jety_test.go
+++ b/jety_test.go
@@ -66,7 +66,7 @@ func TestNewConfigManager(t *testing.T) {
 	if cm.envConfig == nil {
 		t.Error("envConfig not initialized")
 	}
-	if cm.mapConfig == nil {
+	if cm.overrideConfig == nil {
 		t.Error("mapConfig not initialized")
 	}
 	if cm.defaultConfig == nil {
@@ -554,7 +554,7 @@ func TestEnvOverridesDefault(t *testing.T) {
 	}
 }
 
-func TestConfigFileOverridesEnv(t *testing.T) {
+func TestEnvOverridesConfigFile(t *testing.T) {
 	os.Setenv("PORT", "5000")
 	defer os.Unsetenv("PORT")
 
@@ -575,9 +575,9 @@ func TestConfigFileOverridesEnv(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	// Config file should override env and default
-	if got := cm.GetInt("port"); got != 9000 {
-		t.Errorf("GetInt(port) = %d, want 9000 (from file)", got)
+	// Env should override config file (env > file > defaults)
+	if got := cm.GetInt("port"); got != 5000 {
+		t.Errorf("GetInt(port) = %d, want 5000 (env overrides file)", got)
 	}
 }
 
@@ -1347,3 +1347,53 @@ func TestPackageLevelSetEnvPrefixOverrides(t *testing.T) {
 		t.Fatalf("subprocess failed: %v\n%s", err, out)
 	}
 }
+
+func TestPrecedenceChain(t *testing.T) {
+	// Verify: Set > env > file > defaults
+	os.Setenv("PORT", "5000")
+	os.Setenv("HOST", "envhost")
+	os.Setenv("LOG", "envlog")
+	defer os.Unsetenv("PORT")
+	defer os.Unsetenv("HOST")
+	defer os.Unsetenv("LOG")
+
+	dir := t.TempDir()
+	configFile := filepath.Join(dir, "config.yaml")
+	if err := os.WriteFile(configFile, []byte("port: 9000\nhost: filehost\nlog: filelog\nname: filename"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	cm := NewConfigManager()
+	cm.SetDefault("port", 8080)
+	cm.SetDefault("host", "defaulthost")
+	cm.SetDefault("log", "defaultlog")
+	cm.SetDefault("name", "defaultname")
+	cm.SetDefault("extra", "defaultextra")
+
+	cm.SetConfigFile(configFile)
+	if err := cm.SetConfigType("yaml"); err != nil {
+		t.Fatal(err)
+	}
+	if err := cm.ReadInConfig(); err != nil {
+		t.Fatal(err)
+	}
+
+	cm.Set("port", 1111) // Set overrides everything
+
+	// port: Set(1111) > env(5000) > file(9000) > default(8080) → 1111
+	if got := cm.GetInt("port"); got != 1111 {
+		t.Errorf("port: got %d, want 1111 (Set overrides all)", got)
+	}
+	// host: env(envhost) > file(filehost) > default(defaulthost) → envhost
+	if got := cm.GetString("host"); got != "envhost" {
+		t.Errorf("host: got %q, want envhost (env overrides file)", got)
+	}
+	// name: file(filename) > default(defaultname) → filename
+	if got := cm.GetString("name"); got != "filename" {
+		t.Errorf("name: got %q, want filename (file overrides default)", got)
+	}
+	// extra: only default → defaultextra
+	if got := cm.GetString("extra"); got != "defaultextra" {
+		t.Errorf("extra: got %q, want defaultextra (default)", got)
+	}
+}
diff --git a/setters.go b/setters.go
index c5d04fa..b0b7b5a 100644
--- a/setters.go
+++ b/setters.go
@@ -8,7 +8,7 @@ func (c *ConfigManager) SetBool(key string, value bool) {
 	c.mutex.Lock()
 	defer c.mutex.Unlock()
 	lower := strings.ToLower(key)
-	c.mapConfig[lower] = ConfigMap{Key: key, Value: value}
+	c.overrideConfig[lower] = ConfigMap{Key: key, Value: value}
 	c.combinedConfig[lower] = ConfigMap{Key: key, Value: value}
 }
 
@@ -16,7 +16,7 @@ func (c *ConfigManager) SetString(key string, value string) {
 	c.mutex.Lock()
 	defer c.mutex.Unlock()
 	lower := strings.ToLower(key)
-	c.mapConfig[lower] = ConfigMap{Key: key, Value: value}
+	c.overrideConfig[lower] = ConfigMap{Key: key, Value: value}
 	c.combinedConfig[lower] = ConfigMap{Key: key, Value: value}
 }
 
@@ -24,7 +24,7 @@ func (c *ConfigManager) Set(key string, value any) {
 	c.mutex.Lock()
 	defer c.mutex.Unlock()
 	lower := strings.ToLower(key)
-	c.mapConfig[lower] = ConfigMap{Key: key, Value: value}
+	c.overrideConfig[lower] = ConfigMap{Key: key, Value: value}
 	c.combinedConfig[lower] = ConfigMap{Key: key, Value: value}
 }
 
@@ -33,14 +33,14 @@ func (c *ConfigManager) SetDefault(key string, value any) {
 	defer c.mutex.Unlock()
 	lower := strings.ToLower(key)
 	c.defaultConfig[lower] = ConfigMap{Key: key, Value: value}
-	if _, ok := c.mapConfig[lower]; !ok {
+	if _, ok := c.overrideConfig[lower]; !ok {
 		if envVal, ok := c.envConfig[lower]; ok {
-			c.mapConfig[lower] = ConfigMap{Key: key, Value: envVal.Value}
+			c.overrideConfig[lower] = ConfigMap{Key: key, Value: envVal.Value}
 			c.combinedConfig[lower] = ConfigMap{Key: key, Value: envVal.Value}
 		} else {
 			c.combinedConfig[lower] = ConfigMap{Key: key, Value: value}
 		}
 	} else {
-		c.combinedConfig[lower] = c.mapConfig[lower]
+		c.combinedConfig[lower] = c.overrideConfig[lower]
 	}
 }