diff --git a/go.mod b/go.mod
index 5fe5445..52850c7 100644
--- a/go.mod
+++ b/go.mod
@@ -3,11 +3,3 @@ module github.com/sj14/epoch
 go 1.22
 
 retract [v1.2.0, v1.2.3]
-
-require github.com/stretchr/testify v1.9.0
-
-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/go.sum b/go.sum
index 60ce688..e69de29 100644
--- a/go.sum
+++ b/go.sum
@@ -1,10 +0,0 @@
-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 v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
-github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
-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/pkg/epoch/epoch_test.go b/pkg/epoch/epoch_test.go
index c10b119..3150ec9 100644
--- a/pkg/epoch/epoch_test.go
+++ b/pkg/epoch/epoch_test.go
@@ -2,12 +2,29 @@ package epoch
 
 import (
 	"errors"
+	"reflect"
 	"testing"
 	"time"
-
-	"github.com/stretchr/testify/require"
 )
 
+func equalError(t *testing.T, got, want error) {
+	t.Helper()
+
+	if (got == nil && want != nil) ||
+		(got != nil && want == nil) ||
+		(got.Error() != want.Error()) {
+		t.Fatalf("got %q, want %q\n", got, want)
+	}
+}
+
+func equal[T any](t *testing.T, got, want T) {
+	t.Helper()
+
+	if !reflect.DeepEqual(got, want) {
+		t.Fatalf("got '%#v', want '%#v\n", got, want)
+	}
+}
+
 func TestParseUnit(t *testing.T) {
 	testCases := []struct {
 		description string
@@ -46,14 +63,13 @@ func TestParseUnit(t *testing.T) {
 		t.Run(tt.description, func(t *testing.T) {
 			unit, err := ParseUnit(tt.given)
 			if err != nil {
-				require.EqualError(t, tt.expectedErr, err.Error(), err)
+				equalError(t, err, tt.expectedErr)
 				return
 			} else if tt.expectedErr != nil {
-				require.EqualError(t, err, tt.expectedErr.Error(), tt.expectedErr)
+				equalError(t, err, tt.expectedErr)
 				return
 			}
-
-			require.Equal(t, tt.expected, unit)
+			equal(t, unit, tt.expected)
 		})
 	}
 }
@@ -109,14 +125,14 @@ func TestToTimestamp(t *testing.T) {
 		t.Run(tt.description, func(t *testing.T) {
 			timestamp, err := ToTimestamp(tt.given.time, tt.given.unit)
 			if err != nil {
-				require.EqualError(t, tt.expected.err, err.Error(), err)
+				equalError(t, err, tt.expected.err)
 				return
 			} else if tt.expected.err != nil {
-				require.EqualError(t, err, tt.expected.err.Error(), tt.expected.err)
+				equalError(t, err, tt.expected.err)
 				return
 			}
 
-			require.Equal(t, tt.expected.timestamp, timestamp)
+			equal(t, timestamp, tt.expected.timestamp)
 		})
 	}
 }
@@ -172,14 +188,14 @@ func TestParseTimestamp(t *testing.T) {
 		t.Run(tt.description, func(t *testing.T) {
 			timestamp, err := ParseTimestamp(tt.given.timestamp, tt.given.unit)
 			if err != nil {
-				require.EqualError(t, tt.expected.err, err.Error(), err)
+				equalError(t, err, tt.expected.err)
 				return
 			} else if tt.expected.err != nil {
-				require.EqualError(t, err, tt.expected.err.Error(), tt.expected.err)
+				equalError(t, err, tt.expected.err)
 				return
 			}
 
-			require.Equal(t, tt.expected.time.UTC(), timestamp.UTC())
+			equal(t, timestamp.UTC(), tt.expected.time.UTC())
 		})
 	}
 }
@@ -230,7 +246,7 @@ func TestGuessUnit(t *testing.T) {
 	for _, tt := range testCases {
 		t.Run(tt.description, func(t *testing.T) {
 			unit := GuessUnit(tt.given.timestamp, tt.given.ref)
-			require.Equal(t, tt.expected.unit, unit)
+			equal(t, unit, tt.expected.unit)
 		})
 	}
 }
@@ -266,16 +282,16 @@ func TestParseFormatted(t *testing.T) {
 	for _, tt := range testCases {
 		t.Run(tt.description, func(t *testing.T) {
 			parsed, layout, err := ParseFormatted(tt.given.formatted)
-			require.Equal(t, tt.expected.layout, layout)
+			equal(t, layout, tt.expected.layout)
 			if err != nil {
-				require.EqualError(t, tt.expected.err, err.Error(), err)
+				equalError(t, err, tt.expected.err)
 				return
 			} else if tt.expected.err != nil {
-				require.EqualError(t, err, tt.expected.err.Error(), tt.expected.err)
+				equalError(t, err, tt.expected.err)
 				return
 			}
 
-			require.Equal(t, tt.expected.time, parsed)
+			equal(t, parsed, tt.expected.time)
 		})
 	}
 }