diff --git a/README.md b/README.md
index c428bca..b24dd5f 100644
--- a/README.md
+++ b/README.md
@@ -7,13 +7,13 @@ Miscellaneous useful Go packages by [Cleverse](https://about.cleverse.com)
 
 ## utils
 
-Optimized common generic utilities for Cleverse Golang projects.
+Pure Golang optimized generic utilities for Cleverse projects.
 
 [See here](utils/README.md).
 
 ## errors
 
-Package errors adds stacktrace support to errors in go.
+Pure Golang errors library with stacktrace support (for wrapping and formatting an errors).
 
 [See here](errors/README.md).
 
diff --git a/errors/README.md b/errors/README.md
index 242e942..eca7dfa 100644
--- a/errors/README.md
+++ b/errors/README.md
@@ -3,7 +3,7 @@
 
 # errors
 
-Package errors adds stacktrace support to errors in go.
+Pure Golang errors library with stacktrace support (for wrapping and formatting an errors).
 
 ## Installation
 
diff --git a/utils/README.md b/utils/README.md
index acc27bd..e694b87 100644
--- a/utils/README.md
+++ b/utils/README.md
@@ -3,7 +3,7 @@
 
 # utils
 
-Optimized common generic utilities for Cleverse projects.
+Pure Golang optimized generic utilities for Cleverse projects.
 
 ## Installation
 
diff --git a/utils/errors.go b/utils/errors.go
index 6d5507b..6d1f664 100644
--- a/utils/errors.go
+++ b/utils/errors.go
@@ -1,10 +1,7 @@
 package utils
 
 import (
-	"fmt"
 	"reflect"
-
-	"github.com/Cleverse/go-utilities/errors"
 )
 
 // Must is used to simplify error handling.
@@ -21,7 +18,7 @@ func Must[T any](data T, err any, messageArgs ...interface{}) T {
 // warning: this is not safe, use with caution!! (avoid to use it's in runtime)
 func MustNotError[T any](data T, err error) T {
 	if err != nil {
-		panic(errors.WithStack(err))
+		panic(err)
 	}
 	return data
 }
@@ -40,7 +37,7 @@ func UnsafeMust[T any, E any](data T, e E) T {
 // warning: this is not safe, use with caution!! (avoid to use it's in runtime)
 func MustOK[T any](data T, ok bool) T {
 	if !ok {
-		panic(errors.Errorf("got not ok, but should ok"))
+		panic("got not ok, but should ok")
 	}
 	return data
 }
@@ -51,7 +48,7 @@ func MustOK[T any](data T, ok bool) T {
 // warning: this is not safe, use with caution!! (avoid to use it's in runtime)
 func MustNotOK[T any](data T, ok bool) T {
 	if ok {
-		panic(errors.Errorf("got ok, but should not ok"))
+		panic("got ok, but should not ok")
 	}
 	return data
 }
@@ -75,22 +72,8 @@ func must(err any, messageArgs ...interface{}) {
 		if message != "" {
 			panic(message + ": " + e.Error())
 		}
-		panic(errors.WithStack(e))
+		panic(e)
 	default:
 		panic("must: invalid err type '" + reflect.TypeOf(err).Name() + "', should either be a bool or an error")
 	}
 }
-
-func msgFormatter(msgAndArgs ...interface{}) string {
-	switch len(msgAndArgs) {
-	case 0:
-		return ""
-	case 1:
-		if msgAsStr, ok := msgAndArgs[0].(string); ok {
-			return msgAsStr
-		}
-		return fmt.Sprintf("%+v", msgAndArgs[0])
-	default:
-		return fmt.Sprintf(msgAndArgs[0].(string), msgAndArgs[1:]...)
-	}
-}
diff --git a/utils/go.mod b/utils/go.mod
index 80b2c3a..e7d653d 100644
--- a/utils/go.mod
+++ b/utils/go.mod
@@ -1,14 +1,3 @@
 module github.com/Cleverse/go-utilities/utils
 
 go 1.19
-
-require (
-	github.com/Cleverse/go-utilities/errors v0.0.0-20231019072721-442842e3dc09
-	github.com/stretchr/testify v1.8.4
-)
-
-require (
-	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/pmezard/go-difflib v1.0.0 // indirect
-	gopkg.in/yaml.v3 v3.0.1 // indirect
-)
diff --git a/utils/go.sum b/utils/go.sum
index 814bfe2..e69de29 100644
--- a/utils/go.sum
+++ b/utils/go.sum
@@ -1,12 +0,0 @@
-github.com/Cleverse/go-utilities/errors v0.0.0-20231019072721-442842e3dc09 h1:kNAgub14cUBr7uoTxQSrf0qiMNJSzMhIDa8RFdv6hkk=
-github.com/Cleverse/go-utilities/errors v0.0.0-20231019072721-442842e3dc09/go.mod h1:1QK+h746G1DwellQ6KK2rBCJusZqIDTZ9QFVGnUX9+Q=
-github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
-github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
-github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
-github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
-gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/utils/hex.go b/utils/hex.go
index d4bb114..51db106 100644
--- a/utils/hex.go
+++ b/utils/hex.go
@@ -2,8 +2,7 @@ package utils
 
 import (
 	"encoding/hex"
-
-	"github.com/Cleverse/go-utilities/errors"
+	"fmt"
 )
 
 // RandomHex returns a random hex string with the given length.
@@ -62,5 +61,5 @@ func isHexCharacter(c byte) bool {
 // DecodeHex decodes a hex string into a byte slice. str can be prefixed with 0x.
 func DecodeHex(str string) ([]byte, error) {
 	b, err := hex.DecodeString(Trim0xPrefix(str))
-	return b, errors.WithStack(err)
+	return b, fmt.Errorf("decode hex: %w", err)
 }
diff --git a/utils/hex_test.go b/utils/hex_test.go
index 2ebd0e5..0b0b04b 100644
--- a/utils/hex_test.go
+++ b/utils/hex_test.go
@@ -2,8 +2,6 @@ package utils
 
 import (
 	"testing"
-
-	"github.com/stretchr/testify/assert"
 )
 
 func TestHex0XPrefix(t *testing.T) {
@@ -74,9 +72,12 @@ func TestHex0XPrefix(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.Input, func(t *testing.T) {
-			assert := assert.New(t)
-			assert.Equal(tc.Has0xPrefix, Has0xPrefix(tc.Input), "Has0xPrefix should be equal")
-			assert.Equal(tc.Expected, tc.Func(tc.Input), "actual result from `Func(string) string` should equal to expected")
+			if isHasPrefix := Has0xPrefix(tc.Input); tc.Has0xPrefix != isHasPrefix {
+				t.Errorf("expected Has0xPrefix to be %v, but got %v", tc.Has0xPrefix, isHasPrefix)
+			}
+			if actual := tc.Func(tc.Input); tc.Expected != actual {
+				t.Errorf("expected result from `Func(string) string` to be %v, but got %v", tc.Expected, actual)
+			}
 		})
 	}
 }
diff --git a/utils/struct_test.go b/utils/struct_test.go
index d34857c..51dd2d9 100644
--- a/utils/struct_test.go
+++ b/utils/struct_test.go
@@ -3,8 +3,6 @@ package utils
 import (
 	"fmt"
 	"testing"
-
-	"github.com/stretchr/testify/assert"
 )
 
 func TestZeroFieldsEqualStructHasZero(t *testing.T) {
@@ -29,8 +27,8 @@ func TestZeroFieldsEqualStructHasZero(t *testing.T) {
 		}
 		isZero_01 := len(StructZeroFields(val)) > 0
 		isZero_02 := StructHasZero(val)
-		assert.Equal(t, isZero_01, isZero_02)
-		assert.True(t, isZero_01)
+		assertEqual(t, isZero_01, isZero_02)
+		assertTrue(t, isZero_01)
 	}
 	{
 		val := ABC{
@@ -43,14 +41,14 @@ func TestZeroFieldsEqualStructHasZero(t *testing.T) {
 		{
 			isZero_01 := len(StructZeroFields(val)) > 0
 			isZero_02 := StructHasZero(val)
-			assert.Equal(t, isZero_01, isZero_02)
-			assert.False(t, isZero_01)
+			assertEqual(t, isZero_01, isZero_02)
+			assertFalse(t, isZero_01)
 		}
 		{
 			isZero_01 := len(StructZeroFields(val, true)) > 0
 			isZero_02 := StructHasZero(val, true)
-			assert.Equal(t, isZero_01, isZero_02)
-			assert.True(t, isZero_01)
+			assertEqual(t, isZero_01, isZero_02)
+			assertTrue(t, isZero_01)
 		}
 	}
 	{
@@ -65,14 +63,14 @@ func TestZeroFieldsEqualStructHasZero(t *testing.T) {
 		{
 			isZero_01 := len(StructZeroFields(val)) > 0
 			isZero_02 := StructHasZero(val)
-			assert.Equal(t, isZero_01, isZero_02)
-			assert.False(t, isZero_01)
+			assertEqual(t, isZero_01, isZero_02)
+			assertFalse(t, isZero_01)
 		}
 		{
 			isZero_01 := len(StructZeroFields(val, true)) > 0
 			isZero_02 := StructHasZero(val, true)
-			assert.Equal(t, isZero_01, isZero_02)
-			assert.True(t, isZero_01)
+			assertEqual(t, isZero_01, isZero_02)
+			assertTrue(t, isZero_01)
 		}
 	}
 }
@@ -148,7 +146,7 @@ func TestStructZeroFields(t *testing.T) {
 
 	for i, testSpec := range testSpecs {
 		t.Run(fmt.Sprint("#", i+1), func(t *testing.T) {
-			assert.Equal(t, testSpec.ExpectedFields, StructZeroFields(testSpec.Struct, testSpec.CheckNested))
+			assertEqualAny(t, testSpec.ExpectedFields, StructZeroFields(testSpec.Struct, testSpec.CheckNested))
 		})
 	}
 }
@@ -229,7 +227,7 @@ func TestStructHasZero(t *testing.T) {
 
 	for i, testSpec := range testSpecs {
 		t.Run(fmt.Sprint("#", i+1), func(t *testing.T) {
-			assert.Equal(t, testSpec.ExpectedZero, StructHasZero(testSpec.Struct))
+			assertEqual(t, testSpec.ExpectedZero, StructHasZero(testSpec.Struct))
 		})
 	}
 }
@@ -270,14 +268,14 @@ func TestMerge(t *testing.T) {
 
 	result := Merge(&to, from)
 
-	assert.Equal(t, from.A, result.A)
-	assert.NotEqual(t, org.A, result.A)
-	assert.Equal(t, org.B, result.B)
-	assert.NotEqual(t, from.B, result.B)
-	assert.Equal(t, from.C, result.C)
-	assert.NotEqual(t, org.C, result.C)
-	assert.Equal(t, org.D, result.D)
-	assert.NotEqual(t, from.D, result.D)
-	assert.Equal(t, from.E, result.E)
-	assert.NotEqual(t, org.E, result.E)
+	assertEqual(t, from.A, result.A)
+	assertNotEqual(t, org.A, result.A)
+	assertEqual(t, org.B, result.B)
+	assertNotEqual(t, from.B, result.B)
+	assertEqual(t, from.C, result.C)
+	assertNotEqual(t, org.C, result.C)
+	assertEqual(t, org.D, result.D)
+	assertNotEqual(t, from.D, result.D)
+	assertEqual(t, from.E, result.E)
+	assertNotEqual(t, org.E, result.E)
 }
diff --git a/utils/utils.go b/utils/utils.go
index 585f57e..fcac267 100644
--- a/utils/utils.go
+++ b/utils/utils.go
@@ -1,5 +1,7 @@
 package utils
 
+import "fmt"
+
 // Default inspired by Nullish coalescing operator (??) in JavaScript
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Nullish_coalescing
 func Default[T comparable](value T, defaultValue T) (result T) {
@@ -40,3 +42,17 @@ func Empty[T any]() T {
 	var zero T
 	return zero
 }
+
+func msgFormatter(msgAndArgs ...interface{}) string {
+	switch len(msgAndArgs) {
+	case 0:
+		return ""
+	case 1:
+		if msgAsStr, ok := msgAndArgs[0].(string); ok {
+			return msgAsStr
+		}
+		return fmt.Sprintf("%+v", msgAndArgs[0])
+	default:
+		return fmt.Sprintf(msgAndArgs[0].(string), msgAndArgs[1:]...)
+	}
+}
diff --git a/utils/utils_test.go b/utils/utils_test.go
new file mode 100644
index 0000000..90e20fe
--- /dev/null
+++ b/utils/utils_test.go
@@ -0,0 +1,93 @@
+package utils
+
+import (
+	"bytes"
+	"reflect"
+	"testing"
+)
+
+// assertEqual asserts that expected and actual are equal.
+func assertEqual[T comparable](t *testing.T, expected, actual T, msgAndArgs ...interface{}) bool {
+	if expected != actual {
+		if msg := msgFormatter(msgAndArgs...); msg != "" {
+			t.Error(msg)
+		} else {
+			t.Errorf("expected: %v, got: %v", expected, actual)
+		}
+		return false
+	}
+	return true
+}
+
+func assertNotEqual[T comparable](t *testing.T, expected, actual T, msgAndArgs ...interface{}) bool {
+	if expected == actual {
+		if msg := msgFormatter(msgAndArgs...); msg != "" {
+			t.Error(msg)
+		} else {
+			t.Errorf("expected: %v not equal to: %v", expected, actual)
+		}
+		return false
+	}
+	return true
+}
+
+// assertNotEqual asserts that expected and actual are not equal.
+func assertTrue(t *testing.T, actual bool, msgAndArgs ...interface{}) bool {
+	return assertEqual(t, true, actual, msgAndArgs...)
+}
+
+// assertNotEqual asserts that expected and actual are not equal.
+func assertFalse(t *testing.T, actual bool, msgAndArgs ...interface{}) bool {
+	return assertEqual(t, false, actual, msgAndArgs...)
+}
+
+func assertEqualAny(t *testing.T, expected, actual interface{}, msgAndArgs ...interface{}) (equal bool) {
+	// check nil
+	switch {
+	case expected == nil && actual == nil:
+		return true
+	case expected == nil && actual != nil:
+		fallthrough
+	case expected != nil && actual == nil:
+		t.Errorf("expected: %v, got: %v", expected, actual)
+		return false
+	}
+
+	// if types are different, they are not equal.
+	t1 := reflect.TypeOf(expected)
+	t2 := reflect.TypeOf(actual)
+	if t1 != t2 {
+		t.Errorf("type mismatch: expected: %v, got: %v", t1, t2)
+		return false
+	}
+
+	defer func() {
+		if !equal {
+			if msg := msgFormatter(msgAndArgs...); msg != "" {
+				t.Error(msg)
+			} else {
+				t.Errorf("expected: %v, got: %v", expected, actual)
+			}
+		}
+	}()
+
+	// default compare
+	switch expected := expected.(type) {
+	case []byte:
+		actual := actual.([]byte)
+		return bytes.Equal(expected, actual)
+	case []string:
+		actual := actual.([]string)
+		if len(expected) != len(actual) {
+			return false
+		}
+		for i := range expected {
+			if expected[i] != actual[i] {
+				return false
+			}
+		}
+		return true
+	default:
+		return expected == actual
+	}
+}