diff --git a/.github/workflows/riscv64_docker.yml b/.github/workflows/riscv64_docker.yml
index 8d949da..d555ad1 100644
--- a/.github/workflows/riscv64_docker.yml
+++ b/.github/workflows/riscv64_docker.yml
@@ -11,10 +11,11 @@ jobs:
         distro: [
           alpine,
           # centos,
-          # debian, # currently only debian:sid not latest
+          debian, # currently only unstable not latest
           # fedora,
           # opensuse,
-          ubuntu]
+          #ubuntu,
+        ]
       fail-fast: false
     env:
       DISTRO: riscv64_${{ matrix.distro }}
diff --git a/ci/docker/debian/Dockerfile b/ci/docker/debian/Dockerfile
index f44b0c4..fdb7117 100644
--- a/ci/docker/debian/Dockerfile
+++ b/ci/docker/debian/Dockerfile
@@ -1,6 +1,6 @@
 # Create a virtual environment with all tools installed
 # ref: https://hub.docker.com/_/debian
-FROM debian:latest AS env
+FROM debian:unstable AS env
 # Install system build dependencies
 ENV PATH=/usr/local/bin:$PATH
 RUN apt-get update -qq \