diff --git a/.gitignore b/.gitignore
index 5722f21..810858c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -8,6 +8,7 @@
 _obj
 _test
 .idea
+vendor
 
 # Architecture specific extensions/prefixes
 *.[568vq]
@@ -28,3 +29,6 @@ _testmain.go
 # Created by .ignore support plugin (hsz.mobi)
 
 dockerize
+
+# Test coverage related files
+coverage.out
\ No newline at end of file
diff --git a/go.mod b/go.mod
index 3cb1378..ed6f43b 100644
--- a/go.mod
+++ b/go.mod
@@ -6,6 +6,7 @@ require (
 	github.com/Masterminds/sprig/v3 v3.3.0
 	github.com/hpcloud/tail v1.0.0
 	github.com/jwilder/gojq v0.0.0-20161018055142-c550732d4a52
+	github.com/stretchr/testify v1.11.1
 	golang.org/x/net v0.48.0
 )
 
@@ -13,16 +14,19 @@ require (
 	dario.cat/mergo v1.0.2 // indirect
 	github.com/Masterminds/goutils v1.1.1 // indirect
 	github.com/Masterminds/semver/v3 v3.4.0 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/elgs/gosplitargs v0.0.0-20241205072753-cbd889c0f906 // indirect
 	github.com/fsnotify/fsnotify v1.9.0 // indirect
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/huandu/xstrings v1.5.0 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect
 	github.com/mitchellh/reflectwalk v1.0.2 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/shopspring/decimal v1.4.0 // indirect
 	github.com/spf13/cast v1.9.2 // indirect
 	golang.org/x/crypto v0.46.0 // indirect
 	golang.org/x/sys v0.39.0 // indirect
 	gopkg.in/fsnotify.v1 v1.4.7 // indirect
 	gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
diff --git a/go.sum b/go.sum
index b2cdb0a..87da2ef 100644
--- a/go.sum
+++ b/go.sum
@@ -40,14 +40,16 @@ github.com/shopspring/decimal v1.4.0 h1:bxl37RwXBklmTi0C79JfXCEBD1cqqHt0bbgBAGFp
 github.com/shopspring/decimal v1.4.0/go.mod h1:gawqmDU56v4yIKSwfBSFip1HdCCXN8/+DMd9qYNcwME=
 github.com/spf13/cast v1.9.2 h1:SsGfm7M8QOFtEzumm7UZrZdLLquNdzFYfIbEXntcFbE=
 github.com/spf13/cast v1.9.2/go.mod h1:jNfB8QC9IA6ZuY2ZjDp0KtFO2LZZlg4S/7bzP6qqeHo=
-github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
-github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
+github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
 golang.org/x/crypto v0.46.0 h1:cKRW/pmt1pKAfetfu+RCEvjvZkA9RimPbh7bhFjGVBU=
 golang.org/x/crypto v0.46.0/go.mod h1:Evb/oLKmMraqjZ2iQTwDwvCtJkczlDuTmdJXoZVzqU0=
 golang.org/x/net v0.48.0 h1:zyQRTTrjc33Lhh0fBgT/H3oZq9WuvRR5gPC70xpDiQU=
 golang.org/x/net v0.48.0/go.mod h1:+ndRgGjkh8FGtu1w1FGbEC31if4VrNVMuKTgcAAnQRY=
 golang.org/x/sys v0.39.0 h1:CvCKL8MeisomCi6qNZ+wbb0DN9E5AATixKsvNtMoMFk=
 golang.org/x/sys v0.39.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
+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/fsnotify.v1 v1.4.7 h1:xOHLXZwVvI9hhs+cLKq5+I5onOuwQLhQwiu63xxlHs4=
 gopkg.in/fsnotify.v1 v1.4.7/go.mod h1:Tz8NjZHkW78fSQdbUxIjBTcgA1z1m8ZHf0WmKUhAMys=
 gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 h1:uRGJdciOHaEIrze2W8Q3AKkepLTh2hOroT7a+7czfdQ=
diff --git a/main_test.go b/main_test.go
new file mode 100644
index 0000000..57f41d4
--- /dev/null
+++ b/main_test.go
@@ -0,0 +1,148 @@
+package main
+
+import (
+	"os"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMain(m *testing.M) {
+	os.Exit(m.Run())
+}
+
+func TestSliceVarString(t *testing.T) {
+	var sv sliceVar
+	sv.Set("test1")
+	sv.Set("test2")
+	result := sv.String()
+	assert.Equal(t, "test1,test2", result)
+}
+
+func TestHostFlagsVarString(t *testing.T) {
+	var hf hostFlagsVar
+	hf.Set("host1")
+	hf.Set("host2")
+	result := hf.String()
+	assert.Equal(t, "[host1 host2]", result)
+}
+
+func TestExists(t *testing.T) {
+	tempFile, err := os.CreateTemp("", "test-exists")
+	assert.NoError(t, err)
+	defer os.Remove(tempFile.Name())
+
+	existsResult, err := exists(tempFile.Name())
+	assert.NoError(t, err)
+	assert.True(t, existsResult)
+
+	nonExisting := "/path/that/does/not/exist"
+	existsResult, err = exists(nonExisting)
+	assert.NoError(t, err)
+	assert.False(t, existsResult)
+}
+
+func TestContains(t *testing.T) {
+	testMap := map[string]string{
+		"key1": "value1",
+		"key2": "value2",
+	}
+
+	assert.True(t, contains(testMap, "key1"))
+	assert.True(t, contains(testMap, "key2"))
+	assert.False(t, contains(testMap, "key3"))
+}
+
+func TestDefaultValue(t *testing.T) {
+	result, err := defaultValue("test-value")
+	assert.NoError(t, err)
+	assert.Equal(t, "test-value", result)
+
+	result, err = defaultValue("test-value", "default-value")
+	assert.NoError(t, err)
+	assert.Equal(t, "test-value", result)
+
+	result, err = defaultValue(nil, "default-value")
+	assert.NoError(t, err)
+	assert.Equal(t, "default-value", result)
+
+	_, err = defaultValue(nil, nil)
+	assert.Error(t, err)
+
+	_, err = defaultValue()
+	assert.Error(t, err)
+}
+
+func TestParseUrl(t *testing.T) {
+	url := parseUrl("http://example.com/path")
+	assert.Equal(t, "http", url.Scheme)
+	assert.Equal(t, "example.com", url.Host)
+	assert.Equal(t, "/path", url.Path)
+
+	url = parseUrl("https://api.example.com:8080/v1/users")
+	assert.Equal(t, "https", url.Scheme)
+	assert.Equal(t, "api.example.com:8080", url.Host)
+	assert.Equal(t, "/v1/users", url.Path)
+}
+
+func TestAdd(t *testing.T) {
+	result := add(5, 3)
+	assert.Equal(t, 8, result)
+
+	result = add(-1, 1)
+	assert.Equal(t, 0, result)
+
+	result = add(0, 0)
+	assert.Equal(t, 0, result)
+}
+
+func TestIsTrue(t *testing.T) {
+	assert.True(t, isTrue("true"))
+	assert.True(t, isTrue("TRUE"))
+	assert.True(t, isTrue("1"))
+	assert.True(t, isTrue("yes"))
+	assert.True(t, isTrue("on"))
+
+	assert.False(t, isTrue("false"))
+	assert.False(t, isTrue("FALSE"))
+	assert.False(t, isTrue("0"))
+	assert.False(t, isTrue("no"))
+	assert.False(t, isTrue("off"))
+	assert.False(t, isTrue(""))
+	assert.False(t, isTrue("invalid"))
+}
+
+func TestLoop(t *testing.T) {
+	ch, err := loop(3)
+	assert.NoError(t, err)
+
+	var result []int
+	for i := range ch {
+		result = append(result, i)
+	}
+	assert.Equal(t, []int{0, 1, 2}, result)
+
+	ch, err = loop(2, 5)
+	assert.NoError(t, err)
+
+	result = []int{}
+	for i := range ch {
+		result = append(result, i)
+	}
+	assert.Equal(t, []int{2, 3, 4}, result)
+
+	ch, err = loop(0, 10, 2)
+	assert.NoError(t, err)
+
+	result = []int{}
+	for i := range ch {
+		result = append(result, i)
+	}
+	assert.Equal(t, []int{0, 2, 4, 6, 8}, result)
+
+	_, err = loop()
+	assert.Error(t, err)
+
+	_, err = loop(1, 2, 3, 4)
+	assert.Error(t, err)
+}
diff --git a/template.go b/template.go
index b36755b..4a25b9a 100644
--- a/template.go
+++ b/template.go
@@ -72,11 +72,19 @@ func add(arg1, arg2 int) int {
 }
 
 func isTrue(s string) bool {
-	b, err := strconv.ParseBool(strings.ToLower(s))
-	if err == nil {
-		return b
+	lower := strings.ToLower(s)
+	switch lower {
+	case "true", "1", "yes", "on":
+		return true
+	case "false", "0", "no", "off":
+		return false
+	default:
+		b, err := strconv.ParseBool(lower)
+		if err == nil {
+			return b
+		}
+		return false
 	}
-	return false
 }
 
 func jsonQuery(jsonObj string, query string) (interface{}, error) {