diff --git a/Dockerfile b/Dockerfile
index 46f74643..af2e8159 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -16,7 +16,7 @@ RUN export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true && ap
   rm -r /var/lib/apt/lists/*
 
 ENV CARTON_ROOT=/root/.carton
-ENV CARTON_DEFAULT_TOOLCHAIN=wasm-5.8.0-RELEASE
+ENV CARTON_DEFAULT_TOOLCHAIN=wasm-5.9.1-RELEASE
 
 RUN mkdir -p $CARTON_ROOT/sdk && \
   mkdir -p $CARTON_ROOT/sdk/$CARTON_DEFAULT_TOOLCHAIN && \
diff --git a/Sources/CartonHelpers/DefaultToolchain.swift b/Sources/CartonHelpers/DefaultToolchain.swift
index fb7715a2..e105ab8d 100644
--- a/Sources/CartonHelpers/DefaultToolchain.swift
+++ b/Sources/CartonHelpers/DefaultToolchain.swift
@@ -12,5 +12,4 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// TODO: make this `public let defaultToolchainVersion = "wasm-5.9.0-RELEASE"`
-public let defaultToolchainVersion = "wasm-5.9-SNAPSHOT-2023-12-12-a"
+public let defaultToolchainVersion = "wasm-5.9.1-RELEASE"