diff --git a/internal/utils/utils.go b/internal/utils/utils.go
index 9be5310..22ea1c3 100644
--- a/internal/utils/utils.go
+++ b/internal/utils/utils.go
@@ -113,6 +113,13 @@ func IsNil(v interface{}) bool {
 	return v == nil || (reflect.ValueOf(v).Kind() == reflect.Ptr && reflect.ValueOf(v).IsNil())
 }
 
+// MustBeTrue panics when condition is false
+func MustBeTrue(condition bool, errorStr string) {
+	if !condition {
+		panic(errorStr)
+	}
+}
+
 // MustBe panics with errorStr error, if v interface is not of reflect kind
 func MustBe(v interface{}, kind reflect.Kind, errorStr string) {
 	if reflect.TypeOf(v).Kind() != kind {
@@ -165,6 +172,7 @@ func ErrorCatch(err *error) {
 	}
 }
 
+// StringSliceContains checks if slice of strings contains a string
 func StringSliceContains(strings []string, contains string) bool {
 	for _, str := range strings {
 		if str == contains {
diff --git a/postgres/functions.go b/postgres/functions.go
index 6993de4..ddd01db 100644
--- a/postgres/functions.go
+++ b/postgres/functions.go
@@ -69,7 +69,7 @@ var COUNT = jet.COUNT
 // EVERY is aggregate function. Returns true if all input values are true, otherwise false
 var EVERY = jet.EVERY
 
-// MAXf is aggregate function. Returns maximum value of expression across all input values
+// MAX is aggregate function. Returns maximum value of expression across all input values
 var MAX = jet.MAX
 
 // MAXf is aggregate function. Returns maximum value of float expression across all input values
diff --git a/qrm/scan_context.go b/qrm/scan_context.go
index 8141ed7..e3f7f40 100644
--- a/qrm/scan_context.go
+++ b/qrm/scan_context.go
@@ -212,9 +212,7 @@ func (s *scanContext) rowElem(index int) interface{} {
 
 	valuer, ok := s.row[index].(driver.Valuer)
 
-	if !ok {
-		panic("jet: internal error, scan value doesn't implement driver.Valuer")
-	}
+	utils.MustBeTrue(ok, "jet: internal error, scan value doesn't implement driver.Valuer")
 
 	value, err := valuer.Value()
 
diff --git a/qrm/utill.go b/qrm/utill.go
index 20b8b54..7791f9a 100644
--- a/qrm/utill.go
+++ b/qrm/utill.go
@@ -50,9 +50,8 @@ func getSliceElemPtrAt(slicePtrValue reflect.Value, index int) reflect.Value {
 }
 
 func appendElemToSlice(slicePtrValue reflect.Value, objPtrValue reflect.Value) error {
-	if slicePtrValue.IsNil() {
-		panic("jet: internal, slice is nil")
-	}
+	utils.MustBeTrue(!slicePtrValue.IsNil(), "jet: internal, slice is nil")
+
 	sliceValue := slicePtrValue.Elem()
 	sliceElemType := sliceValue.Type().Elem()