diff --git a/.drone.yml b/.drone.yml
index 057d760..6182098 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -24,6 +24,6 @@ steps:
   - go test -parallel 10 -race ./... 
 
 - name: golangci-lint
-  image: golangci/golangci-lint:v1.39
+  image: golangci/golangci-lint:v1.53
   commands:
   - golangci-lint run
diff --git a/.golangci.yml b/.golangci.yml
index 23e5557..29a6459 100644
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -22,6 +22,8 @@ linters-settings:
       suggest-new: true
     misspell:
       locale: US  
+    varnamelen:
+      min-name-length: 2
 
 linters:
     enable-all: true
@@ -30,6 +32,16 @@ linters:
       - maligned
       - interfacer
       - scopelint
+      - exhaustruct
+      - depguard
+      - nolintlint
+      #deprecated
+      - structcheck
+      - varcheck
+      - golint
+      - deadcode
+      - ifshort
+      - nosnakecase
 
 issues:
   # Excluding configuration per-path, per-linter, per-text and per-source
@@ -39,8 +51,14 @@ issues:
         - gomnd
         - exhaustivestruct
         - wrapcheck
+        - exhaustruct
+        - varnamelen
+        - tenv
+        - funlen
     - path: test/*
       linters:
         - gomnd
         - exhaustivestruct
         - wrapcheck
+        - exhaustruct
+        - varnamelen
diff --git a/client.go b/client.go
index 434cfa2..508115e 100644
--- a/client.go
+++ b/client.go
@@ -49,17 +49,21 @@ type provider struct {
 	factory  func(ctx context.Context) (Provider, error)
 }
 
-func (p *provider) init(ctx context.Context) (err error) {
+func (p *provider) init(ctx context.Context) error {
 	if atomic.LoadUint32(&p.done) == 0 {
 		if !p.mu.TryLock() {
 			return fmt.Errorf("%w", ErrInitFactory)
 		}
 		defer atomic.StoreUint32(&p.done, 1)
 		defer p.mu.Unlock()
-		p.provider, err = p.factory(ctx)
+
+		var err error
+		if p.provider, err = p.factory(ctx); err != nil {
+			return fmt.Errorf("init provider factory:%w", err)
+		}
 	}
 
-	return err
+	return nil
 }
 
 func (p *provider) Watch(ctx context.Context, key Key, callback WatchCallback) error {
@@ -67,8 +71,13 @@ func (p *provider) Watch(ctx context.Context, key Key, callback WatchCallback) e
 		return fmt.Errorf("init read:%w", err)
 	}
 
-	if watch, ok := p.provider.(WatchProvider); ok {
-		return watch.Watch(ctx, key, callback)
+	watch, ok := p.provider.(WatchProvider)
+	if !ok {
+		return nil
+	}
+
+	if err := watch.Watch(ctx, key, callback); err != nil {
+		return fmt.Errorf("factory provider: %w", err)
 	}
 
 	return nil
@@ -79,7 +88,12 @@ func (p *provider) Read(ctx context.Context, key Key) (Variable, error) {
 		return Variable{}, fmt.Errorf("init read:%w", err)
 	}
 
-	return p.provider.Read(ctx, key)
+	variable, err := p.provider.Read(ctx, key)
+	if err != nil {
+		return Variable{}, fmt.Errorf("factory provider: %w", err)
+	}
+
+	return variable, nil
 }
 
 type Client struct {
@@ -96,10 +110,12 @@ func (c *Client) key(name string) Key {
 	}
 }
 
+// Value get value by name.
+// nolint: ireturn
 func (c *Client) Value(ctx context.Context, name string) (Value, error) {
 	variable, err := c.Variable(ctx, name)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("variable:%w", err)
 	}
 
 	return variable.Value, nil
diff --git a/client_example_test.go b/client_example_test.go
index 33384f3..7550fb5 100644
--- a/client_example_test.go
+++ b/client_example_test.go
@@ -284,11 +284,11 @@ func ExampleClient_Value_factory() {
 
 	fmt.Printf("listen from env: %d\n", port.Int())
 	fmt.Printf("title from json: %v\n", title.String())
-	fmt.Printf("title from yaml: %v\n", yamlTitle.String())
+	fmt.Printf("yaml title: %v\n", yamlTitle.String())
 	fmt.Printf("struct from json: %+v\n", cfg)
 	// Output:
 	// listen from env: 8080
 	// title from json: config title
-	// title from yaml: yaml title
+	// yaml title: yaml title
 	// struct from json: {Duration:21m0s Enabled:true}
 }
diff --git a/key/helpers.go b/key/helpers.go
index 311fcfa..acd672f 100644
--- a/key/helpers.go
+++ b/key/helpers.go
@@ -9,14 +9,14 @@ import (
 
 func LastIndex(sep string, factory config.KeyFactory) func(ctx context.Context, key config.Key) (string, string) {
 	return func(ctx context.Context, key config.Key) (string, string) {
-		k := factory(ctx, key)
+		name := factory(ctx, key)
 
-		idx := strings.LastIndex(k, sep)
+		idx := strings.LastIndex(name, sep)
 		if idx == -1 {
-			return k, ""
+			return name, ""
 		}
 
-		return k[0:idx], k[idx+len(sep):]
+		return name[0:idx], name[idx+len(sep):]
 	}
 }
 
diff --git a/provider/arg/provider.go b/provider/arg/provider.go
index 5164bd1..e106f05 100644
--- a/provider/arg/provider.go
+++ b/provider/arg/provider.go
@@ -21,15 +21,16 @@ func WithKeyFactory(factory config.KeyFactory) Option {
 }
 
 func New(opts ...Option) *Provider {
-	p := Provider{
-		key: key.Name,
+	prov := Provider{
+		key:  key.Name,
+		args: make(map[string][]string, len(os.Args[1:])),
 	}
 
 	for _, opt := range opts {
-		opt(&p)
+		opt(&prov)
 	}
 
-	return &p
+	return &prov
 }
 
 type Provider struct {
@@ -38,9 +39,10 @@ type Provider struct {
 }
 
 // nolint: cyclop
-func (p *Provider) parseOne(arg string) (name, val string, err error) {
+// return name, value, error.
+func (p *Provider) parseOne(arg string) (string, string, error) {
 	if arg[0] != '-' {
-		return
+		return "", "", nil
 	}
 
 	numMinuses := 1
@@ -49,19 +51,21 @@ func (p *Provider) parseOne(arg string) (name, val string, err error) {
 		numMinuses++
 	}
 
-	name = strings.TrimSpace(arg[numMinuses:])
+	name := strings.TrimSpace(arg[numMinuses:])
 	if len(name) == 0 {
-		return
+		return name, "", nil
 	}
 
 	if name[0] == '-' || name[0] == '=' {
 		return "", "", fmt.Errorf("%w: bad flag syntax: %s", config.ErrInvalidValue, arg)
 	}
 
-	for i := 1; i < len(name); i++ {
-		if name[i] == '=' || name[i] == ' ' {
-			val = strings.TrimSpace(name[i+1:])
-			name = name[0:i]
+	var val string
+
+	for idx := 1; idx < len(name); idx++ {
+		if name[idx] == '=' || name[idx] == ' ' {
+			val = strings.TrimSpace(name[idx+1:])
+			name = name[0:idx]
 
 			break
 		}
@@ -79,8 +83,6 @@ func (p *Provider) parse() error {
 		return nil
 	}
 
-	p.args = make(map[string][]string, len(os.Args[1:]))
-
 	for _, arg := range os.Args[1:] {
 		name, value, err := p.parseOne(arg)
 		if err != nil {
@@ -105,32 +107,36 @@ func (p *Provider) IsSupport(ctx context.Context, key config.Key) bool {
 
 func (p *Provider) Read(ctx context.Context, key config.Key) (config.Variable, error) {
 	if err := p.parse(); err != nil {
-		return config.Variable{Provider: p.Name()}, err
+		return config.Variable{
+			Name:     "",
+			Value:    nil,
+			Provider: p.Name(),
+		}, err
 	}
 
-	k := p.key(ctx, key)
-	if val, ok := p.args[k]; ok {
+	name := p.key(ctx, key)
+	if val, ok := p.args[name]; ok {
 		switch {
 		case len(val) == 1:
 			return config.Variable{
-				Name:     k,
+				Name:     name,
 				Provider: p.Name(),
 				Value:    value.JString(val[0]),
 			}, nil
 		default:
-			var n yaml.Node
+			var yNode yaml.Node
 
-			if err := yaml.Unmarshal([]byte("["+strings.Join(val, ",")+"]"), &n); err != nil {
+			if err := yaml.Unmarshal([]byte("["+strings.Join(val, ",")+"]"), &yNode); err != nil {
 				return config.Variable{}, fmt.Errorf("arg: failed unmarshal yaml:%w", err)
 			}
 
 			return config.Variable{
-				Name:     k,
+				Name:     name,
 				Provider: p.Name(),
-				Value:    value.Decode(n.Decode),
+				Value:    value.Decode(yNode.Decode),
 			}, nil
 		}
 	}
 
-	return config.Variable{Name: k, Provider: p.Name()}, config.ErrVariableNotFound
+	return config.Variable{}, fmt.Errorf("%w: %s", config.ErrVariableNotFound, name)
 }
diff --git a/provider/env/provider.go b/provider/env/provider.go
index 9102c16..e55520a 100644
--- a/provider/env/provider.go
+++ b/provider/env/provider.go
@@ -19,17 +19,17 @@ func WithKeyFactory(factory config.KeyFactory) Option {
 }
 
 func New(opts ...Option) *Provider {
-	p := Provider{
+	provider := Provider{
 		key: func(ctx context.Context, k config.Key) string {
 			return strings.ToUpper(key.NsAppName("_")(ctx, k))
 		},
 	}
 
 	for _, opt := range opts {
-		opt(&p)
+		opt(&provider)
 	}
 
-	return &p
+	return &provider
 }
 
 type Provider struct {
@@ -45,17 +45,14 @@ func (p *Provider) IsSupport(ctx context.Context, key config.Key) bool {
 }
 
 func (p *Provider) Read(ctx context.Context, key config.Key) (config.Variable, error) {
-	k := p.key(ctx, key)
-	if val, ok := os.LookupEnv(k); ok {
+	name := p.key(ctx, key)
+	if val, ok := os.LookupEnv(name); ok {
 		return config.Variable{
-			Name:     k,
+			Name:     name,
 			Provider: p.Name(),
 			Value:    value.JString(val),
 		}, nil
 	}
 
-	return config.Variable{
-		Name:     k,
-		Provider: p.Name(),
-	}, config.ErrVariableNotFound
+	return config.Variable{}, config.ErrVariableNotFound
 }
diff --git a/provider/etcd/provider.go b/provider/etcd/provider.go
index 0274356..91d187d 100644
--- a/provider/etcd/provider.go
+++ b/provider/etcd/provider.go
@@ -44,16 +44,16 @@ func (p *Provider) Name() string {
 }
 
 func (p *Provider) Read(ctx context.Context, key config.Key) (config.Variable, error) {
-	k := p.key(ctx, key)
+	name := p.key(ctx, key)
 
-	resp, err := p.client.Get(ctx, k, client.WithPrefix())
+	resp, err := p.client.Get(ctx, name, client.WithPrefix())
 	if err != nil {
-		return config.Variable{}, fmt.Errorf("%w: key:%s, prov:%s", err, k, p.Name())
+		return config.Variable{}, fmt.Errorf("%w: key:%s, prov:%s", err, name, p.Name())
 	}
 
-	val, err := p.resolve(k, resp.Kvs)
+	val, err := p.resolve(name, resp.Kvs)
 	if err != nil {
-		return config.Variable{}, fmt.Errorf("%w: key:%s, prov:%s", err, k, p.Name())
+		return config.Variable{}, fmt.Errorf("%w: key:%s, prov:%s", err, name, p.Name())
 	}
 
 	return val, nil
@@ -94,6 +94,7 @@ func (p *Provider) resolve(key string, kvs []*pb.KeyValue) (config.Variable, err
 			return config.Variable{
 				Name:     key,
 				Provider: p.Name(),
+				Value:    nil,
 			}, nil
 		case string(kv.Key) == key:
 			return config.Variable{
@@ -104,8 +105,5 @@ func (p *Provider) resolve(key string, kvs []*pb.KeyValue) (config.Variable, err
 		}
 	}
 
-	return config.Variable{
-		Name:     key,
-		Provider: p.Name(),
-	}, config.ErrVariableNotFound
+	return config.Variable{}, fmt.Errorf("%w: name %s", config.ErrVariableNotFound, key)
 }
diff --git a/provider/ini/provider.go b/provider/ini/provider.go
index 01fed28..e06c15b 100644
--- a/provider/ini/provider.go
+++ b/provider/ini/provider.go
@@ -13,10 +13,12 @@ import (
 var _ config.Provider = (*Provider)(nil)
 
 func New(data *ini.File) *Provider {
+	const nameParts = 2
+
 	return &Provider{
 		data: data,
 		resolve: func(ctx context.Context, key config.Key) (string, string) {
-			keys := strings.SplitN(key.Name, "/", 2)
+			keys := strings.SplitN(key.Name, "/", nameParts)
 			if len(keys) == 1 {
 				return "", keys[0]
 			}
@@ -46,12 +48,12 @@ func (p *Provider) Read(ctx context.Context, key config.Key) (config.Variable, e
 
 	iniSection, err := p.data.GetSection(section)
 	if err != nil {
-		return config.Variable{}, fmt.Errorf("%w: %s: %v", config.ErrVariableNotFound, p.Name(), err)
+		return config.Variable{}, fmt.Errorf("%w: %s: %w", config.ErrVariableNotFound, p.Name(), err)
 	}
 
 	iniKey, err := iniSection.GetKey(name)
 	if err != nil {
-		return config.Variable{}, fmt.Errorf("%w: %s: %v", config.ErrVariableNotFound, p.Name(), err)
+		return config.Variable{}, fmt.Errorf("%w: %s: %w", config.ErrVariableNotFound, p.Name(), err)
 	}
 
 	return config.Variable{
diff --git a/provider/json/provider.go b/provider/json/provider.go
index bacf6c2..13d1647 100644
--- a/provider/json/provider.go
+++ b/provider/json/provider.go
@@ -33,7 +33,7 @@ func NewFile(path string, opts ...Option) (*Provider, error) {
 		return nil, fmt.Errorf("%w: unable to read config file %#q: file not found or unreadable", err, path)
 	}
 
-	return New(file), nil
+	return New(file, opts...), nil
 }
 
 type Option func(*Provider)
diff --git a/provider/toml/provider.go b/provider/toml/provider.go
index 9a149a9..6129413 100644
--- a/provider/toml/provider.go
+++ b/provider/toml/provider.go
@@ -24,16 +24,16 @@ func NewFile(file string, opts ...Option) (*Provider, error) {
 type Option func(*Provider)
 
 func configure(tree *toml.Tree, opts ...Option) *Provider {
-	p := &Provider{
+	prov := &Provider{
 		tree: tree,
 		key:  key.Name,
 	}
 
 	for _, opt := range opts {
-		opt(p)
+		opt(prov)
 	}
 
-	return p
+	return prov
 }
 
 func New(data []byte, opts ...Option) (*Provider, error) {
diff --git a/provider/toml/value.go b/provider/toml/value.go
index cd310bd..7d2ab9d 100644
--- a/provider/toml/value.go
+++ b/provider/toml/value.go
@@ -30,11 +30,11 @@ func (s Value) ParseInt() (int, error) {
 func (s Value) Unmarshal(target interface{}) error {
 	b, err := json.Marshal(s.Raw())
 	if err != nil {
-		return fmt.Errorf("%w: %s", config.ErrInvalidValue, err)
+		return fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
 	}
 
 	if err := json.Unmarshal(b, target); err != nil {
-		return fmt.Errorf("%w: %s", config.ErrInvalidValue, err)
+		return fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
 	}
 
 	return nil
diff --git a/provider/vault/secret.go b/provider/vault/secret.go
index cfe09e8..0e56ce4 100644
--- a/provider/vault/secret.go
+++ b/provider/vault/secret.go
@@ -20,16 +20,16 @@ func WithSecretResolve(f func(context.Context, config.Key) (string, string)) Sec
 }
 
 func NewSecretKV2(client *api.Client, opts ...SecretOption) *SecretKV2 {
-	s := SecretKV2{
+	prov := SecretKV2{
 		client:  client,
 		resolve: key.LastIndexField(":", "value", key.PrefixName("secret/data/", key.NsAppName("/"))),
 	}
 
 	for _, opt := range opts {
-		opt(&s)
+		opt(&prov)
 	}
 
-	return &s
+	return &prov
 }
 
 type SecretKV2 struct {
@@ -50,26 +50,26 @@ func (p *SecretKV2) Name() string {
 func (p *SecretKV2) Read(ctx context.Context, key config.Key) (config.Variable, error) {
 	path, field := p.resolve(ctx, key)
 
-	s, err := p.client.Logical().Read(path)
+	secret, err := p.client.Logical().Read(path)
 	if err != nil {
 		return config.Variable{}, fmt.Errorf("%w: path:%s, field:%s, provider:%s", err, path, field, p.Name())
 	}
 
-	if s == nil || len(s.Data) == 0 {
+	if secret == nil || len(secret.Data) == 0 {
 		return config.Variable{}, fmt.Errorf("%w: path:%s, field:%s, provider:%s", config.ErrVariableNotFound, path, field, p.Name())
 	}
 
-	if len(s.Warnings) > 0 {
+	if len(secret.Warnings) > 0 {
 		return config.Variable{},
-			fmt.Errorf("%w: warn: %s, path:%s, field:%s, provider:%s", config.ErrVariableNotFound, s.Warnings, path, field, p.Name())
+			fmt.Errorf("%w: warn: %s, path:%s, field:%s, provider:%s", config.ErrVariableNotFound, secret.Warnings, path, field, p.Name())
 	}
 
-	d, ok := s.Data["data"].(map[string]interface{})
+	data, ok := secret.Data["data"].(map[string]interface{})
 	if !ok {
 		return config.Variable{}, fmt.Errorf("%w: path:%s, field:%s, provider:%s", config.ErrVariableNotFound, path, field, p.Name())
 	}
 
-	if val, ok := d[field]; ok {
+	if val, ok := data[field]; ok {
 		return config.Variable{
 			Name:     path + field,
 			Provider: p.Name(),
@@ -77,9 +77,9 @@ func (p *SecretKV2) Read(ctx context.Context, key config.Key) (config.Variable,
 		}, nil
 	}
 
-	md, err := json.Marshal(d)
+	md, err := json.Marshal(data)
 	if err != nil {
-		return config.Variable{}, fmt.Errorf("%w: %s", config.ErrInvalidValue, err)
+		return config.Variable{}, fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
 	}
 
 	return config.Variable{
diff --git a/provider/watcher/provider.go b/provider/watcher/provider.go
index b97f923..fece95c 100644
--- a/provider/watcher/provider.go
+++ b/provider/watcher/provider.go
@@ -15,7 +15,7 @@ var (
 )
 
 func New(duration time.Duration, provider config.Provider, opts ...Option) *Provider {
-	p := &Provider{
+	prov := &Provider{
 		Provider: provider,
 		ticker:   time.NewTicker(duration),
 		logger: func(_ context.Context, msg string) {
@@ -24,10 +24,10 @@ func New(duration time.Duration, provider config.Provider, opts ...Option) *Prov
 	}
 
 	for _, opt := range opts {
-		opt(p)
+		opt(prov)
 	}
 
-	return p
+	return prov
 }
 
 func WithLogger(l func(context.Context, string)) Option {
diff --git a/provider/watcher/provider_test.go b/provider/watcher/provider_test.go
index 2cfaa6a..47611c9 100644
--- a/provider/watcher/provider_test.go
+++ b/provider/watcher/provider_test.go
@@ -22,12 +22,13 @@ func (p *provider) Name() string {
 	return "test"
 }
 
-func (p *provider) Read(ctx context.Context, k config.Key) (config.Variable, error) {
+func (p *provider) Read(context.Context, config.Key) (config.Variable, error) {
 	p.cnt++
 
 	return config.Variable{
-		Name:  "tmpname",
-		Value: value.JString(fmt.Sprint(p.cnt)),
+		Name:     "tmpname",
+		Provider: p.Name(),
+		Value:    value.JString(fmt.Sprint(p.cnt)),
 	}, nil
 }
 
diff --git a/provider/yaml/provider.go b/provider/yaml/provider.go
index 4d70fcb..7e173a1 100644
--- a/provider/yaml/provider.go
+++ b/provider/yaml/provider.go
@@ -14,7 +14,7 @@ import (
 
 var _ config.Provider = (*Provider)(nil)
 
-func keyFactory(ctx context.Context, key config.Key) []string {
+func keyFactory(_ context.Context, key config.Key) []string {
 	return strings.Split(key.Name, "/")
 }
 
@@ -37,15 +37,15 @@ func New(yml []byte, opts ...Option) (*Provider, error) {
 }
 
 func create(opts ...Option) *Provider {
-	p := Provider{
+	prov := Provider{
 		key: keyFactory,
 	}
 
 	for _, opt := range opts {
-		opt(&p)
+		opt(&prov)
 	}
 
-	return &p
+	return &prov
 }
 
 type Option func(*Provider)
@@ -76,8 +76,8 @@ type node struct {
 	*yaml.Node
 }
 
-func (n *node) read(name string, k []string) (config.Variable, error) {
-	val, err := getData(n.Node.Content[0].Content, k)
+func (n *node) read(name string, keys []string) (config.Variable, error) {
+	val, err := getData(n.Node.Content[0].Content, keys)
 	if err != nil {
 		if errors.Is(err, config.ErrVariableNotFound) {
 			return config.Variable{}, fmt.Errorf("%w: %s", config.ErrVariableNotFound, name)
@@ -87,20 +87,20 @@ func (n *node) read(name string, k []string) (config.Variable, error) {
 	}
 
 	return config.Variable{
-		Name:     strings.Join(k, "."),
+		Name:     strings.Join(keys, "."),
 		Provider: name,
 		Value:    value.Decode(val),
 	}, nil
 }
 
 func getData(node []*yaml.Node, keys []string) (func(interface{}) error, error) {
-	for i := len(node) - 1; i > 0; i -= 2 {
-		if node[i-1].Value == keys[0] {
+	for idx := len(node) - 1; idx > 0; idx -= 2 {
+		if node[idx-1].Value == keys[0] {
 			if len(keys) > 1 {
-				return getData(node[i].Content, keys[1:])
+				return getData(node[idx].Content, keys[1:])
 			}
 
-			return node[i].Decode, nil
+			return node[idx].Decode, nil
 		}
 	}
 
diff --git a/provider/yaml/watch.go b/provider/yaml/watch.go
index 624a094..2da862a 100644
--- a/provider/yaml/watch.go
+++ b/provider/yaml/watch.go
@@ -33,10 +33,10 @@ func (p *Watch) Read(ctx context.Context, key config.Key) (config.Variable, erro
 		return config.Variable{}, fmt.Errorf("yaml_file: read error: %w", err)
 	}
 
-	var n yaml.Node
-	if err = yaml.Unmarshal(in, &n); err != nil {
+	var yNode yaml.Node
+	if err = yaml.Unmarshal(in, &yNode); err != nil {
 		return config.Variable{}, fmt.Errorf("yaml_file: unmarshal error: %w", err)
 	}
 
-	return p.prov.With(&n).Read(ctx, key)
+	return p.prov.With(&yNode).Read(ctx, key)
 }
diff --git a/value/decode.go b/value/decode.go
index 6c30114..8258fda 100644
--- a/value/decode.go
+++ b/value/decode.go
@@ -1,3 +1,4 @@
+// nolint: nonamedreturns
 package value
 
 import (
diff --git a/value/empty.go b/value/empty.go
index dac3e27..6b889ad 100644
--- a/value/empty.go
+++ b/value/empty.go
@@ -8,7 +8,7 @@ type Empty struct {
 	Err error
 }
 
-func (e Empty) Unmarshal(val interface{}) error {
+func (e Empty) Unmarshal(_ interface{}) error {
 	return e.Err
 }
 
diff --git a/value/helpers.go b/value/helpers.go
index e03bed7..5e93d09 100644
--- a/value/helpers.go
+++ b/value/helpers.go
@@ -12,7 +12,7 @@ import (
 func ParseDuration(raw string) (time.Duration, error) {
 	d, err := time.ParseDuration(raw)
 	if err != nil {
-		return 0, fmt.Errorf("%w: %s", config.ErrInvalidValue, err)
+		return 0, fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
 	}
 
 	return d, nil
@@ -21,7 +21,7 @@ func ParseDuration(raw string) (time.Duration, error) {
 func ParseInt(s string) (int64, error) {
 	i, err := strconv.ParseInt(s, 10, 64)
 	if err != nil {
-		return 0, fmt.Errorf("%w: %s", config.ErrInvalidValue, err)
+		return 0, fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
 	}
 
 	return i, nil
@@ -30,7 +30,7 @@ func ParseInt(s string) (int64, error) {
 func ParseUint(s string) (uint64, error) {
 	i, err := strconv.ParseUint(s, 10, 64)
 	if err != nil {
-		return 0, fmt.Errorf("%w: %s", config.ErrInvalidValue, err)
+		return 0, fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
 	}
 
 	return i, nil
@@ -39,7 +39,7 @@ func ParseUint(s string) (uint64, error) {
 func Atoi(s string) (int, error) {
 	i, err := strconv.Atoi(s)
 	if err != nil {
-		return 0, fmt.Errorf("%w: %s", config.ErrInvalidValue, err)
+		return 0, fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
 	}
 
 	return i, nil
@@ -48,7 +48,7 @@ func Atoi(s string) (int, error) {
 func ParseTime(s string) (time.Time, error) {
 	i, err := time.Parse(time.RFC3339, s)
 	if err != nil {
-		return time.Time{}, fmt.Errorf("%w: %s", config.ErrInvalidValue, err)
+		return time.Time{}, fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
 	}
 
 	return i, nil
@@ -57,7 +57,7 @@ func ParseTime(s string) (time.Time, error) {
 func ParseFloat(s string) (float64, error) {
 	f, err := strconv.ParseFloat(s, 64)
 	if err != nil {
-		return 0, fmt.Errorf("%w: %s", config.ErrInvalidValue, err)
+		return 0, fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
 	}
 
 	return f, nil
@@ -66,7 +66,7 @@ func ParseFloat(s string) (float64, error) {
 func ParseBool(s string) (bool, error) {
 	b, err := strconv.ParseBool(s)
 	if err != nil {
-		return false, fmt.Errorf("%w: %s", config.ErrInvalidValue, err)
+		return false, fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
 	}
 
 	return b, nil
@@ -74,7 +74,7 @@ func ParseBool(s string) (bool, error) {
 
 func JUnmarshal(b []byte, v interface{}) error {
 	if err := json.Unmarshal(b, v); err != nil {
-		return fmt.Errorf("%w: %s", config.ErrInvalidValue, err)
+		return fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
 	}
 
 	return nil
diff --git a/value/value.go b/value/value.go
index ac0f24b..727fd86 100644
--- a/value/value.go
+++ b/value/value.go
@@ -76,7 +76,7 @@ func (s Value) Unmarshal(target interface{}) error {
 	if v, ok := s.Raw().([]byte); ok {
 		err := json.Unmarshal(v, target)
 		if err != nil {
-			return fmt.Errorf("%w: %s", config.ErrInvalidValue, err)
+			return fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
 		}
 
 		return nil