diff --git a/core/mem/raw.odin b/core/mem/raw.odin
index c4c5182e6..99712e9e5 100644
--- a/core/mem/raw.odin
+++ b/core/mem/raw.odin
@@ -58,3 +58,14 @@ raw_dynamic_array_data :: proc(a: $T/[dynamic]$E) -> ^E {
 raw_data :: proc{raw_array_data, raw_string_data, raw_slice_data, raw_dynamic_array_data};
 
 
+Poly_Raw_Map_Entry :: struct($Key, $Value: typeid) {
+	hash:  uintptr,
+	next:  int,
+	key:   Key,
+	value: Value,	
+}
+
+Poly_Raw_Map :: struct($Key, $Value: typeid) {
+	hashes:  []int,
+	entries: [dynamic]Poly_Raw_Map_Entry(Key, Value),
+}
\ No newline at end of file
diff --git a/core/runtime/core_builtin.odin b/core/runtime/core_builtin.odin
index 9a90800c4..88e769056 100644
--- a/core/runtime/core_builtin.odin
+++ b/core/runtime/core_builtin.odin
@@ -523,6 +523,15 @@ resize_dynamic_array :: proc(array: ^$T/[dynamic]$E, length: int, loc := #caller
 	return true;
 }
 
+@builtin
+map_insert :: proc(m: ^$T/map[$K]$V, key: K, value: V, loc := #caller_location) -> (ptr: ^V) {
+	key, value := key, value;
+	h := __get_map_header(m);
+	hash := __get_map_hash(&key);
+	
+	data := uintptr(__dynamic_map_set(h, hash, &value, loc));
+	return (^V)(data + h.value_offset);
+}
 
 
 @builtin
diff --git a/core/runtime/dynamic_map_internal.odin b/core/runtime/dynamic_map_internal.odin
index 8bb8975b6..6e54ba441 100644
--- a/core/runtime/dynamic_map_internal.odin
+++ b/core/runtime/dynamic_map_internal.odin
@@ -193,27 +193,28 @@ __dynamic_map_reserve :: proc(using header: Map_Header, cap: int, loc := #caller
 
 }
 __dynamic_map_rehash :: proc(using header: Map_Header, new_count: int, loc := #caller_location) #no_bounds_check {
-	new_header: Map_Header = header;
-	nm := Raw_Map{};
-	nm.entries.allocator = m.entries.allocator;
-	nm.hashes = m.hashes;
-	new_header.m = &nm;
-
 	c := context;
 	if m.entries.allocator.procedure != nil {
 		c.allocator = m.entries.allocator;
 	}
 	context = c;
+	
+	nm := Raw_Map{};
+	nm.entries.allocator = m.entries.allocator;
+	nm.hashes = m.hashes;
+	
+	new_header: Map_Header = header;
+	new_header.m = &nm;
 
 	new_count := new_count;
 	new_count = max(new_count, 2*m.entries.len);
 
-	__dynamic_array_reserve(&nm.entries, entry_size, entry_align, m.entries.len, loc);
 	__slice_resize(&nm.hashes, new_count, m.entries.allocator, loc);
 	for i in 0 ..< new_count {
 		nm.hashes[i] = -1;
 	}
 
+	__dynamic_array_reserve(&nm.entries, entry_size, entry_align, m.entries.len, loc);
 	for i in 0 ..< m.entries.len {
 		if len(nm.hashes) == 0 {
 			__dynamic_map_grow(new_header, loc);
@@ -253,7 +254,7 @@ __dynamic_map_get :: proc(h: Map_Header, hash: Map_Hash) -> rawptr {
 	return nil;
 }
 
-__dynamic_map_set :: proc(h: Map_Header, hash: Map_Hash, value: rawptr, loc := #caller_location) #no_bounds_check {
+__dynamic_map_set :: proc(h: Map_Header, hash: Map_Hash, value: rawptr, loc := #caller_location) -> ^Map_Entry_Header #no_bounds_check {
 	index: int;
 	assert(value != nil);
 
@@ -277,7 +278,7 @@ __dynamic_map_set :: proc(h: Map_Header, hash: Map_Hash, value: rawptr, loc := #
 
 	e := __dynamic_map_get_entry(h, index);
 	e.hash = hash.hash;
-
+	
 	key := rawptr(uintptr(e) + h.key_offset);
 	mem_copy(key, hash.key_ptr, h.key_size);
 
@@ -286,7 +287,11 @@ __dynamic_map_set :: proc(h: Map_Header, hash: Map_Hash, value: rawptr, loc := #
 
 	if __dynamic_map_full(h) {
 		__dynamic_map_grow(h, loc);
+		index = __dynamic_map_find(h, hash).entry_index;
+		assert(index >= 0);
 	}
+	
+	return __dynamic_map_get_entry(h, index);
 }
 
 
@@ -297,7 +302,7 @@ __dynamic_map_grow :: proc(using h: Map_Header, loc := #caller_location) {
 }
 
 __dynamic_map_full :: #force_inline proc "contextless" (using h: Map_Header) -> bool {
-	return int(0.75 * f64(len(m.hashes))) <= m.entries.cap;
+	return int(0.75 * f64(len(m.hashes))) <= m.entries.len;
 }