diff --git a/implementations/javascript/package.json b/implementations/javascript/package.json
index 1261192..406bb29 100644
--- a/implementations/javascript/package.json
+++ b/implementations/javascript/package.json
@@ -1,6 +1,6 @@
 {
   "name": "preserves",
-  "version": "0.1.1",
+  "version": "0.2.0",
   "description": "Experimental data serialization format",
   "homepage": "https://gitlab.com/preserves/preserves",
   "license": "Apache-2.0",
diff --git a/implementations/python/setup.py b/implementations/python/setup.py
index 2cee4d2..ea7a3b7 100644
--- a/implementations/python/setup.py
+++ b/implementations/python/setup.py
@@ -5,7 +5,7 @@ except ImportError:
 
 setup(
     name="preserves",
-    version="0.1.1",
+    version="0.2.0",
     author="Tony Garnock-Jones",
     author_email="tonyg@leastfixedpoint.com",
     license="Apache Software License",
diff --git a/implementations/rust/Cargo.toml b/implementations/rust/Cargo.toml
index 9f89158..ca6e15a 100644
--- a/implementations/rust/Cargo.toml
+++ b/implementations/rust/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "preserves"
-version = "0.3.1"
+version = "0.4.0"
 authors = ["Tony Garnock-Jones <tonyg@leastfixedpoint.com>"]
 edition = "2018"
 description = "Implementation of the Preserves serialization format via serde."