diff --git a/src/boot/boot.janet b/src/boot/boot.janet
index 616c1e53..3f953c43 100644
--- a/src/boot/boot.janet
+++ b/src/boot/boot.janet
@@ -2142,6 +2142,19 @@
     :buffer (string x)
     x))
 
+(defn thaw
+  `Thaw an object (make it mutable) and do a deep copy, making
+  child value also mutable. Closures, fibers, and abstract
+  types will not be recursively thawed, but all other types will`
+  [ds]
+  (case (type ds)
+    :array (walk-ind thaw ds)
+    :tuple (walk-ind thaw ds)
+    :table (walk-dict thaw (table/proto-flatten ds))
+    :struct (walk-dict thaw (struct/proto-flatten ds))
+    :string (buffer ds)
+    ds))
+
 (defn macex
   ``Expand macros completely.
   `on-binding` is an optional callback for whenever a normal symbolic binding
diff --git a/test/suite0010.janet b/test/suite0010.janet
index 5ac0cd16..b41142e8 100644
--- a/test/suite0010.janet
+++ b/test/suite0010.janet
@@ -253,4 +253,13 @@
 # Check missing struct proto bug.
 (assert (struct/getproto (struct/with-proto {:a 1} :b 2 :c nil)) "missing struct proto")
 
+# Test thaw and freeze
+(def table-to-freeze @{:c 22 :b [1 2 3 4] :d @"test" :e "test2"})
+(def table-to-freeze-with-inline-proto @{:a @[1 2 3] :b @[1 2 3 4] :c 22 :d @"test" :e @"test2"})
+(def struct-to-thaw (struct/with-proto {:a [1 2 3]} :c 22 :b [1 2 3 4] :d "test" :e "test2"))
+(table/setproto table-to-freeze @{:a @[1 2 3]})
+(assert (deep= {:a [1 2 3] :b [1 2 3 4] :c 22 :d "test" :e "test2"} (freeze table-to-freeze)))
+(assert (deep= table-to-freeze-with-inline-proto (thaw table-to-freeze)))
+(assert (deep= table-to-freeze-with-inline-proto (thaw struct-to-thaw)))
+
 (end-suite)