diff --git a/Cargo.toml b/Cargo.toml
index 4b1af0b9..842438c0 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -15,7 +15,7 @@ resolver = "2"
 
 # Global settings for our crates
 [workspace.package]
-version = "0.3.0"
+version = "0.4.0"
 edition = "2021"
 license = "Zlib"
 repository = "https://github.com/trifectatechfoundation/zlib-rs"
@@ -37,7 +37,7 @@ libz-sys = { version = "1.1.19", default-features = false, features = ["zlib-ng"
 arbitrary = { version = "1.0" }
 quickcheck = { version = "1.0.3", default-features = false, features = [] }
 
-libz-rs-sys = { version = "0.3.0", path = "./libz-rs-sys", default-features = false }
-zlib-rs = { version = "0.3.0", path = "./zlib-rs", default-features = false }
+libz-rs-sys = { version = "0.4.0", path = "./libz-rs-sys", default-features = false }
+zlib-rs = { version = "0.4.0", path = "./zlib-rs", default-features = false }
 dynamic-libz-sys = { path = "./dynamic-libz-sys" }
 
diff --git a/libz-rs-sys-cdylib/Cargo.toml b/libz-rs-sys-cdylib/Cargo.toml
index cba12580..be89213b 100644
--- a/libz-rs-sys-cdylib/Cargo.toml
+++ b/libz-rs-sys-cdylib/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "libz-rs-sys-cdylib"
-version = "0.3.0"
+version = "0.4.0"
 edition = "2021"
 readme = "README.md"
 license = "Zlib"
@@ -21,4 +21,4 @@ rust-allocator = ["libz-rs-sys/rust-allocator", "libz-rs-sys/std"] # by default,
 custom-prefix = ["libz-rs-sys/custom-prefix"] # use the LIBZ_RS_SYS_PREFIX to prefix all exported symbols
 
 [dependencies]
-libz-rs-sys = { version = "0.3.0", path = "../libz-rs-sys", default-features = false }
+libz-rs-sys = { version = "0.4.0", path = "../libz-rs-sys", default-features = false }