diff --git a/datok_test.go b/datok_test.go
index 6f2dc11..9e0d9a6 100644
--- a/datok_test.go
+++ b/datok_test.go
@@ -11,6 +11,8 @@
 	"github.com/stretchr/testify/assert"
 )
 
+var dat *DaTokenizer
+
 func tmatch(tok Tokenizer, s string) bool {
 	b := make([]byte, 0, 2048)
 	w := bytes.NewBuffer(b)
@@ -168,7 +170,10 @@
 
 func TestDoubleArrayFullTokenizer(t *testing.T) {
 	assert := assert.New(t)
-	dat := LoadDatokFile("testdata/tokenizer.datok")
+
+	if dat == nil {
+		dat = LoadDatokFile("testdata/tokenizer.datok")
+	}
 	assert.NotNil(dat)
 	assert.True(dat.LoadFactor() >= 70)
 	assert.Equal(dat.epsilon, 1)
@@ -207,7 +212,10 @@
 func TestDoubleArrayFullTokenizerTransduce(t *testing.T) {
 	assert := assert.New(t)
 
-	dat := LoadDatokFile("testdata/tokenizer.datok")
+	if dat == nil {
+		dat = LoadDatokFile("testdata/tokenizer.datok")
+	}
+
 	assert.NotNil(dat)
 
 	b := make([]byte, 0, 2048)
@@ -236,7 +244,11 @@
 
 func TestDoubleArrayFullTokenizerSentenceSplitter(t *testing.T) {
 	assert := assert.New(t)
-	dat := LoadDatokFile("testdata/tokenizer.datok")
+
+	if dat == nil {
+		dat = LoadDatokFile("testdata/tokenizer.datok")
+	}
+
 	assert.NotNil(dat)
 
 	b := make([]byte, 0, 2048)
@@ -326,7 +338,11 @@
 
 func TestDoubleArrayFullTokenizerTokenSplitter(t *testing.T) {
 	assert := assert.New(t)
-	dat := LoadDatokFile("testdata/tokenizer.datok")
+
+	if dat == nil {
+		dat = LoadDatokFile("testdata/tokenizer.datok")
+	}
+
 	assert.NotNil(dat)
 
 	b := make([]byte, 0, 2048)
@@ -872,7 +888,10 @@
 func TestDoubleArrayFullTokenizerXML(t *testing.T) {
 	assert := assert.New(t)
 
-	dat := LoadDatokFile("testdata/tokenizer.datok")
+	if dat == nil {
+		dat = LoadDatokFile("testdata/tokenizer.datok")
+	}
+
 	assert.NotNil(dat)
 
 	b := make([]byte, 0, 2048)
diff --git a/matrix_test.go b/matrix_test.go
index e27dd12..1a3f7b0 100644
--- a/matrix_test.go
+++ b/matrix_test.go
@@ -20,6 +20,8 @@
 Archive:  Ich bin kein zip. D'dorf Ku'damm Lu'hafen M'gladbach W'schaft.
 Mach's macht's was'n ist's haste willste kannste biste kriegste.`
 
+var mat *MatrixTokenizer
+
 func TestMatrixFullTokenizer(t *testing.T) {
 	assert := assert.New(t)
 	foma := LoadFomaFile("testdata/simpletok.fst")
@@ -162,7 +164,9 @@
 func TestMatrixFullTokenizerTransduce(t *testing.T) {
 	assert := assert.New(t)
 
-	mat := LoadMatrixFile("testdata/tokenizer.matok")
+	if mat == nil {
+		mat = LoadMatrixFile("testdata/tokenizer.matok")
+	}
 
 	assert.NotNil(mat)
 
@@ -191,7 +195,10 @@
 
 func TestMatrixFullTokenizerMatrixSentenceSplitter(t *testing.T) {
 	assert := assert.New(t)
-	mat := LoadMatrixFile("testdata/tokenizer.matok")
+
+	if mat == nil {
+		mat = LoadMatrixFile("testdata/tokenizer.matok")
+	}
 
 	b := make([]byte, 0, 2048)
 	w := bytes.NewBuffer(b)
@@ -288,7 +295,9 @@
 func TestMatrixFullTokenizerTokenSplitter(t *testing.T) {
 	assert := assert.New(t)
 
-	mat := LoadMatrixFile("testdata/tokenizer.matok")
+	if mat == nil {
+		mat = LoadMatrixFile("testdata/tokenizer.matok")
+	}
 
 	b := make([]byte, 0, 2048)
 	w := bytes.NewBuffer(b)
@@ -826,7 +835,9 @@
 func TestMatrixFullTokenizerXML(t *testing.T) {
 	assert := assert.New(t)
 
-	mat := LoadMatrixFile("testdata/tokenizer.matok")
+	if mat == nil {
+		mat = LoadMatrixFile("testdata/tokenizer.matok")
+	}
 
 	assert.NotNil(mat)
 
@@ -867,7 +878,9 @@
 func TestMatokDatokEquivalence(t *testing.T) {
 	assert := assert.New(t)
 
-	mat := LoadMatrixFile("testdata/tokenizer.matok")
+	if mat == nil {
+		mat = LoadMatrixFile("testdata/tokenizer.matok")
+	}
 	dat := LoadDatokFile("testdata/tokenizer.datok")
 
 	r := strings.NewReader(s)
@@ -894,7 +907,9 @@
 func TestMatrixFullTokenizerCallbackTransduce(t *testing.T) {
 	assert := assert.New(t)
 
-	mat := LoadMatrixFile("testdata/tokenizer.matok")
+	if mat == nil {
+		mat = LoadMatrixFile("testdata/tokenizer.matok")
+	}
 
 	assert.NotNil(mat)
 
@@ -911,7 +926,9 @@
 func TestMatrixFullTokenizerTextTreatment(t *testing.T) {
 	assert := assert.New(t)
 
-	mat := LoadMatrixFile("testdata/tokenizer.matok")
+	if mat == nil {
+		mat = LoadMatrixFile("testdata/tokenizer.matok")
+	}
 
 	assert.NotNil(mat)
 
@@ -926,7 +943,9 @@
 func TestMatrixTrimming(t *testing.T) {
 	assert := assert.New(t)
 
-	mat := LoadMatrixFile("testdata/tokenizer.matok")
+	if mat == nil {
+		mat = LoadMatrixFile("testdata/tokenizer.matok")
+	}
 
 	assert.NotNil(mat)
 
diff --git a/token_writer.go b/token_writer.go
index 11179d3..bccb1bd 100644
--- a/token_writer.go
+++ b/token_writer.go
@@ -89,7 +89,7 @@
 
 	// Collect sentence positions and maybe sentence boundaries
 	if flags&SENTENCE_POS != 0 {
-		tw.SentenceEnd = func(offset int) {
+		tw.SentenceEnd = func(_ int) {
 
 			// Add end position of last token to sentence boundary
 			// TODO: This only works if token positions are taking into account