diff --git a/re_test.go b/re_test.go
new file mode 100644
index 0000000..9ee3ff1
--- /dev/null
+++ b/re_test.go
@@ -0,0 +1,31 @@
+package main
+
+import (
+	"slices"
+	"testing"
+)
+
+var reTests = []struct {
+	re     string
+	str    string
+	result []matchIndex
+}{
+	{"a", "abc", []matchIndex{{0, 1}}},
+	{"a", "bca", []matchIndex{{2, 3}}},
+	{"l", "ggllgg", []matchIndex{{2, 3}, {3, 4}}},
+	{"(b|c)", "abdceb", []matchIndex{{1, 2}, {3, 4}, {5, 6}}},
+	{"a*", "brerereraaaaabbbbb", []matchIndex{{8, 13}}},
+}
+
+func TestFindAllMatches(t *testing.T) {
+	for _, test := range reTests {
+		t.Run(test.re+" "+test.str, func(t *testing.T) {
+			re_postfix := shuntingYard(test.re)
+			startState := thompson(re_postfix)
+			matchIndices := findAllMatches(startState, test.str)
+			if !slices.Equal(test.result, matchIndices) {
+				t.Errorf("Wanted %v	Got %v\n", test.result, matchIndices)
+			}
+		})
+	}
+}