diff --git a/assert.go b/assert.go
index 7d5f90e..791b600 100644
--- a/assert.go
+++ b/assert.go
@@ -2,28 +2,32 @@ package assert
 
 import (
 	"reflect"
-	"runtime"
-	"testing"
+
+	"github.com/google/go-cmp/cmp"
 )
 
 // Assert is a helper for tests
-type Assert func(bool, ...interface{})
+type Assert struct {
+	t T
+}
+
+func (a Assert) f(ok bool, msg []interface{}, format string, extra ...interface{}) {
+	if !ok {
+		if format != `` {
+			msg = prepMsg(msg, format, extra...)
+		}
+		if msg == nil {
+			msg = []interface{}{`Assertion failed`}
+		}
+		msg = append(append([]interface{}{shell(1) + shell(97) + shell(41) + `FAIL!` + shell(0) + shell(1)}, msg...), shell(0), "\n")
+		a.t.Helper()
+		a.t.Error(msg...)
+	}
+}
 
 // New returns a new Assert
-func New(t *testing.T) Assert {
-	a := func(ok bool, msg ...interface{}) {
-		if !ok {
-			if msg == nil {
-				msg = []interface{}{`Assertion failed`}
-			}
-			msg = append(append([]interface{}{shell(1) + shell(97) + shell(41) + `FAIL!` + shell(0) + shell(1)}, msg...), shell(0), "\n")
-			t.Helper()
-			t.Error(msg...)
-		}
-	}
-
-	f := runtime.FuncForPC(reflect.ValueOf(a).Pointer())
-	ts[f] = t
+func New(t T) Assert {
+	a := Assert{t}
 
 	return a
 }
@@ -34,16 +38,14 @@ func New(t *testing.T) Assert {
 
 // True asserts the given value is true
 func (a Assert) True(actual bool, msg ...interface{}) {
-	t(a).Helper()
-	msg = prepMsg(msg, `Should be true, but it isn't`)
-	a(actual, msg...)
+	a.t.Helper()
+	a.f(actual, msg, `Should be true, but it isn't`)
 }
 
-// False sserts the given value is false
+// False asserts the given value is false
 func (a Assert) False(actual bool, msg ...interface{}) {
-	t(a).Helper()
-	msg = prepMsg(msg, `Should be false, but it isn't`)
-	a(!actual, msg...)
+	a.t.Helper()
+	a.f(!actual, msg, `Should be false, but it isn't`)
 }
 
 ///// Nil /////
@@ -64,87 +66,76 @@ func isNil(val interface{}) bool {
 
 // Nil asserts the given value is nil
 func (a Assert) Nil(actual interface{}, msg ...interface{}) {
-	t(a).Helper()
-	msg = prepMsg(msg, `Should be nil, but got %#v`, actual)
-
-	a(isNil(actual), msg...)
+	a.t.Helper()
+	a.f(isNil(actual), msg, `Should be nil, but got %#v`, actual)
 }
 
-// NotNil sserts the given value is not nil
+// NotNil asserts the given value is not nil
 func (a Assert) NotNil(actual interface{}, msg ...interface{}) {
-	t(a).Helper()
-	msg = prepMsg(msg, `Should not be nil, but it is`)
-
-	a(!isNil(actual), msg...)
+	a.t.Helper()
+	a.f(!isNil(actual), msg, `Should not be nil, but it is`)
 }
 
 ///// Errors /////
 
 // Error asserts the given error is not nil
 func (a Assert) Error(actual error, msg ...interface{}) {
-	t(a).Helper()
-	msg = prepMsg(msg, `Expected an error, but got nil`)
-	a(actual != nil, msg...)
+	a.t.Helper()
+	a.f(actual != nil, msg, `Expected an error, but got nil`)
 }
 
-// NoError asserts the given error is not nil
+// NoError asserts the given error is nil
 func (a Assert) NoError(actual error, msg ...interface{}) {
-	t(a).Helper()
-	msg = prepMsg(msg, `Expected no error, but got %#v`, actual)
-	a(actual == nil, msg...)
+	a.t.Helper()
+	a.f(actual == nil, msg, `Expected no error, but got %#v`, actual)
 }
 
 ///// Comparisons /////
 
 // Eq asserts the given values match
 func (a Assert) Eq(expected, actual interface{}, msg ...interface{}) {
-	t(a).Helper()
+	a.t.Helper()
 	if reflect.TypeOf(expected) != reflect.TypeOf(actual) {
-		msg = prepMsg(msg, `Expected %T(%#v), but got %T(%#v)`, expected, expected, actual, actual)
-		a(false, msg...)
+		a.f(false, msg, `Expected %T(%#v), but got %T(%#v)`, expected, expected, actual, actual)
 		return
 	}
 
-	msg = prepMsg(msg, `Expected %#v, but got %#v`, expected, actual)
-	a(expected == actual, msg...)
+	a.f(expected == actual, msg, `Expected %#v, but got %#v`, expected, actual)
 }
 
 // Ne asserts the given values don't match
 func (a Assert) Ne(expected, actual interface{}, msg ...interface{}) {
-	t(a).Helper()
-	msg = prepMsg(msg, `Should not be %#v, but it is`, expected)
-	a(expected != actual, msg...)
+	a.t.Helper()
+	a.f(expected != actual, msg, `Should not be %#v, but it is`, expected)
 }
 
 ///// Lists /////
 
 // Contains asserts the expected value is in the given list
 func (a Assert) Contains(expected, list interface{}, msg ...interface{}) {
-	t(a).Helper()
+	a.t.Helper()
 
 	rlist := reflect.ValueOf(list)
-	a(rlist.Kind() == reflect.Slice || rlist.Kind() == reflect.Array, `Can only call assert.Contains on a slice or array`)
+	a.f(rlist.Kind() == reflect.Slice || rlist.Kind() == reflect.Array, nil, `Can only call assert.Contains on a slice or array`)
 	for i := 0; i < rlist.Len(); i++ {
 		if rlist.Index(i).Interface() == expected {
 			return
 		}
 	}
 
-	msg = prepMsg(msg, `Expected %#v to be in %#v, but it isn't`, expected, list)
-	a(false, msg...)
+	a.f(false, msg, `Expected %#v to be in %#v, but it isn't`, expected, list)
 }
 
 // SameElements asserts the values have the same elements. It ignores the order of the elements
 func (a Assert) SameElements(expected, actual interface{}, msg ...interface{}) {
-	t(a).Helper()
+	a.t.Helper()
 
 	rexpected, ractual := reflect.ValueOf(expected), reflect.ValueOf(actual)
-	a(rexpected.Kind() == reflect.Slice || rexpected.Kind() == reflect.Array, `Can only call assert.SameElements on a slice or array`)
-	a(ractual.Kind() == reflect.Slice || ractual.Kind() == reflect.Array, `Can only call assert.SameElements on a slice or array`)
+	a.f(rexpected.Kind() == reflect.Slice || rexpected.Kind() == reflect.Array, nil, `Can only call assert.SameElements on a slice or array`)
+	a.f(ractual.Kind() == reflect.Slice || ractual.Kind() == reflect.Array, nil, `Can only call assert.SameElements on a slice or array`)
 
-	msg = prepMsg(msg, `Expected elements of %#v to match %#v, but they don't`, expected, actual)
 	if rexpected.Len() != ractual.Len() {
-		a(false, msg...)
+		a.f(false, msg, `Expected elements of %#v to match %#v, but they don't`, expected, actual)
 		return
 	}
 
@@ -162,5 +153,24 @@ func (a Assert) SameElements(expected, actual interface{}, msg ...interface{}) {
 		return
 	}
 
-	a(false, msg...)
+	a.f(false, msg, ``)
+}
+
+// Cmp assert wrapper for go-cmp
+func (a Assert) Cmp(expected, actual interface{}, opts ...cmp.Option) {
+	a.t.Helper()
+	diff := cmp.Diff(expected, actual, opts...)
+	if diff == `` {
+		return
+	}
+
+	a.f(false, nil, "\n"+diff)
+}
+
+// NCmp assert wrapper for go-cmp but fails when !Equal
+func (a Assert) NCmp(expected, actual interface{}, opts ...cmp.Option) {
+	a.t.Helper()
+
+	ok := cmp.Equal(expected, actual, opts...)
+	a.f(!ok, nil, `Should not be %#v, but it is`, expected)
 }
diff --git a/assert_test.go b/assert_test.go
new file mode 100644
index 0000000..0b31a12
--- /dev/null
+++ b/assert_test.go
@@ -0,0 +1,194 @@
+package assert
+
+import (
+	"testing"
+	"time"
+)
+
+// -----------------------------------------
+//  Slices
+// -----------------------------------------
+
+func TestSameElementsSlices(t *testing.T) {
+	assert := New(t)
+	ft, fa := newFakeT()
+
+	a, b := []int{1, 2}, []int{1, 2}
+	fa.SameElements(a, a)
+	assert.False(ft.GotError())
+
+	fa.SameElements(a, b)
+	assert.False(ft.GotError())
+
+	b = []int{2, 1}
+	fa.SameElements(b, a) // SameElements ignores order
+	assert.False(ft.GotError())
+
+	b = []int{1, 2, 3}
+	fa.SameElements(b, a)
+	assert.True(ft.GotError())
+
+	b = []int{2, 3}
+	fa.SameElements(b, a)
+	assert.True(ft.GotError())
+}
+
+func TestCmpSlices(t *testing.T) {
+	assert := New(t)
+	ft, fa := newFakeT()
+
+	a, b := []int{1, 2}, []int{1, 2}
+	fa.Cmp(a, a)
+	assert.False(ft.GotError())
+
+	fa.Cmp(a, b)
+	assert.False(ft.GotError())
+
+	b = []int{2, 1}
+	fa.Cmp(a, b) // Cmp does not accept different order
+	assert.True(ft.GotError())
+
+	b = []int{1, 2, 3}
+	fa.Cmp(a, b)
+	assert.True(ft.GotError())
+
+	b = []int{2, 3}
+	fa.Cmp(a, b)
+	assert.True(ft.GotError())
+}
+
+// -----------------------------------------
+//  Maps
+// -----------------------------------------
+
+func TestCmpMaps(t *testing.T) {
+	assert := New(t)
+	ft, fa := newFakeT()
+
+	a, b := map[int]int{1: 2, 3: 4}, map[int]int{1: 2, 3: 4}
+	fa.Cmp(a, a)
+	assert.False(ft.GotError())
+
+	fa.Cmp(a, b)
+	assert.False(ft.GotError())
+
+	b = map[int]int{1: 2, 3: 5}
+	fa.Cmp(a, b)
+	assert.True(ft.GotError())
+
+	b = map[int]int{1: 2, 3: 4, 5: 6}
+	fa.Cmp(a, b)
+	assert.True(ft.GotError())
+
+	b = map[int]int{1: 2}
+	fa.Cmp(a, b)
+	assert.True(ft.GotError())
+}
+
+// -----------------------------------------
+//  Pointers
+// -----------------------------------------
+
+func TestEqPointers(t *testing.T) {
+	assert := New(t)
+	ft, fa := newFakeT()
+
+	var a, b int
+	fa.Eq(&a, &a)
+	assert.False(ft.GotError())
+
+	fa.Eq(&a, &b)
+	assert.True(ft.GotError())
+
+	fa.Eq(&b, &a)
+	assert.True(ft.GotError())
+}
+
+func TestCmpPointers(t *testing.T) {
+	assert := New(t)
+	ft, fa := newFakeT()
+
+	type B struct {
+		Value int
+	}
+	type A struct {
+		B *B
+	}
+
+	fa.Cmp(A{B: &B{1}}, A{&B{1}})
+	assert.False(ft.GotError())
+
+	fa.Cmp(A{B: &B{1}}, A{&B{2}})
+	assert.True(ft.GotError())
+
+	fa.Cmp(A{B: &B{1}}, A{nil})
+	assert.True(ft.GotError())
+}
+
+// -----------------------------------------
+//  Timezones
+// -----------------------------------------
+
+func mustLoadLocation(zone string) *time.Location {
+	loc, err := time.LoadLocation(zone)
+	if err != nil {
+		panic(err)
+	}
+
+	return loc
+}
+
+var locAmsterdam = mustLoadLocation(`Europe/Amsterdam`)
+var locTokyo = mustLoadLocation(`Asia/Tokyo`)
+
+func TestEqTimezones(t *testing.T) {
+	assert := New(t)
+	ft, fa := newFakeT()
+
+	ti := time.Now()
+	ti, ti2 := ti.In(locAmsterdam), ti.In(locTokyo)
+
+	fa.Eq(ti, ti2)
+	assert.True(ft.GotError())
+}
+
+func TestCmpTimezones(t *testing.T) {
+	assert := New(t)
+	ft, fa := newFakeT()
+
+	type A struct {
+		Time time.Time
+	}
+
+	ti := time.Now()
+	ti2 := ti.In(time.UTC)
+	fa.Cmp(&A{ti}, &A{ti2})
+	assert.False(ft.GotError())
+
+	ti2 = ti.In(locAmsterdam)
+	fa.Cmp(&A{ti}, &A{ti2})
+	assert.False(ft.GotError())
+
+	ti = ti.In(locTokyo)
+	fa.Cmp(&A{ti}, &A{ti2})
+	assert.False(ft.GotError())
+
+	ti2 = ti2.Add(time.Second)
+	fa.Cmp(&A{ti}, &A{ti2})
+	assert.True(ft.GotError())
+}
+
+func TestNCmp(t *testing.T) {
+	assert := New(t)
+	ft, fa := newFakeT()
+
+	type A struct {
+		S string
+	}
+
+	fa.NCmp(A{"not"}, A{"equal"})
+	assert.False(ft.GotError())
+
+	fa.NCmp(A{"equal"}, A{"equal"})
+	assert.True(ft.GotError())
+}
diff --git a/faket_test.go b/faket_test.go
new file mode 100644
index 0000000..1a494e0
--- /dev/null
+++ b/faket_test.go
@@ -0,0 +1,23 @@
+package assert
+
+type fakeT struct {
+	gotError bool
+}
+
+func newFakeT() (*fakeT, Assert) {
+	var ft fakeT
+	return &ft, New(&ft)
+}
+
+func (t *fakeT) Error(_ ...interface{}) {
+	t.gotError = true
+}
+
+func (_ *fakeT) Helper() {}
+
+func (t *fakeT) GotError() bool {
+	r := t.gotError
+	t.gotError = false
+
+	return r
+}
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..55a7857
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,5 @@
+module git.fuyu.moe/Fuyu/assert
+
+go 1.14
+
+require github.com/google/go-cmp v0.4.0
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..4430646
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,3 @@
+github.com/google/go-cmp v0.4.0 h1:xsAVV57WRhGj6kEIi8ReJzQlHHqcBYCElAvkovg3B/4=
+github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
diff --git a/helper.go b/helper.go
index 67cc4a9..d8d5e63 100644
--- a/helper.go
+++ b/helper.go
@@ -2,10 +2,7 @@ package assert
 
 import (
 	"fmt"
-	"reflect"
-	"runtime"
 	"strconv"
-	"testing"
 )
 
 func prepMsg(msg []interface{}, format string, args ...interface{}) []interface{} {
@@ -15,10 +12,3 @@ func prepMsg(msg []interface{}, format string, args ...interface{}) []interface{
 func shell(i int) string {
 	return "\x1B[" + strconv.Itoa(i) + "m"
 }
-
-var ts = map[*runtime.Func]*testing.T{}
-
-func t(a Assert) *testing.T {
-	f := runtime.FuncForPC(reflect.ValueOf(a).Pointer())
-	return ts[f]
-}
diff --git a/type.go b/type.go
new file mode 100644
index 0000000..1c9a1fd
--- /dev/null
+++ b/type.go
@@ -0,0 +1,7 @@
+package assert
+
+// T is an interface of what we use from testing.T
+type T interface {
+	Error(...interface{})
+	Helper()
+}