diff --git a/pkg/minimum_window_substring/main.go b/pkg/minimum_window_substring/main.go
new file mode 100644
index 0000000..a1f33c0
--- /dev/null
+++ b/pkg/minimum_window_substring/main.go
@@ -0,0 +1,95 @@
+package minimumwindowsubstring
+
+import "fmt"
+
+type Set[T comparable] map[T]int
+
+type Substring struct {
+	Main  string
+	Left  int
+	Right int
+	Set   Set[byte]
+}
+
+func Better(a, b string) string {
+	if len(a) == 0 {
+		return b
+	} else if len(b) < len(a) {
+		return b
+	}
+
+	return a
+}
+
+func NewSubstring(s string) Substring {
+	return Substring{s, 0, len(s) - 1, NewSet(s)}
+}
+
+func (s Set[T]) SubsetOf(t Set[T]) bool {
+	for k := range s {
+		if s[k] > t[k] {
+			return false
+		}
+	}
+
+	return true
+}
+
+func NewSet(t string) Set[byte] {
+	set := Set[byte]{}
+	for i := range t {
+		set[t[i]]++
+	}
+
+	return set
+}
+
+func (s *Substring) CullLeft(t Substring) {
+	for s.Set[s.Main[s.Left]] > t.Set[s.Main[s.Left]] {
+		s.Set[s.Main[s.Left]]--
+		s.Left++
+	}
+
+	fmt.Println("CANNOT CULL", string(s.Main[s.Left]))
+}
+
+func (s *Substring) IncRight() bool {
+	if s.Right == len(s.Main)-1 {
+		return false
+	}
+
+	s.Right++
+	s.Set[s.Main[s.Right]]++
+	return true
+}
+
+func (s Substring) String() string {
+	return s.Main[s.Left : s.Right+1]
+}
+
+func (s *Substring) CullRight(t Substring) {
+	for s.Set[s.Main[s.Right]] > t.Set[s.Main[s.Right]] {
+		s.Set[s.Main[s.Right]]--
+		s.Right--
+	}
+}
+
+func minWindow(s string, t string) string {
+	ss, tt := NewSubstring(s), NewSubstring(t)
+	best_answer := ""
+
+	if !tt.Set.SubsetOf(ss.Set) {
+		return best_answer
+	}
+
+	ss.CullRight(tt)
+	ss.CullLeft(tt)
+	best_answer = Better(best_answer, ss.String())
+
+	for ss.IncRight() {
+		ss.CullLeft(tt)
+		best_answer = Better(best_answer, ss.String())
+	}
+
+	return best_answer
+}