diff --git a/Cargo.toml b/Cargo.toml
index 658379a..0522e21 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,7 +7,7 @@ default = ["sleef"]
 
 [package]
 name = "ndelement"
-version = "0.2.1"
+version = "0.2.1-dev"
 edition = "2021"
 authors = ["Matthew Scroggs <rust@mscroggs.co.uk>"]
 description = "n-dimensional finite element definition library."
diff --git a/pyproject.toml b/pyproject.toml
index c512c80..941f0aa 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "maturin"
 
 [project]
 name = "ndelement"
-version = "0.2.1"
+version = "0.2.1-dev"
 description = "n-dimensional finite element definition library."
 readme = "README.md"
 requires-python = ">=3.8"