diff --git a/Cargo.toml b/Cargo.toml
index 41decdd..0f9442e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 edition = "2021"
 name = "hc-spin-rust-utils"
-version = "0.400.0-rc.0"
+version = "0.500.0-dev.0"
 
 [lib]
 crate-type = ["cdylib"]
diff --git a/package.json b/package.json
index f01dd07..f06e94b 100644
--- a/package.json
+++ b/package.json
@@ -4,7 +4,7 @@
     "type": "git",
     "url": "https://github.com/holochain/hc-spin-rust-utils"
   },
-  "version": "0.400.0-dev.2",
+  "version": "0.500.0-dev.0",
   "main": "index.js",
   "types": "index.d.ts",
   "napi": {