diff --git a/.devcontainer/cuda12.0-gcc13/devcontainer.json b/.devcontainer/cuda12.0-gcc13/devcontainer.json
deleted file mode 100644
index 0f1b6ce772..0000000000
--- a/.devcontainer/cuda12.0-gcc13/devcontainer.json
+++ /dev/null
@@ -1,53 +0,0 @@
-{
-  "shutdownAction": "stopContainer",
-  "image": "rapidsai/devcontainers:24.10-cpp-gcc13-cuda12.0",
-  "hostRequirements": {
-    "gpu": "optional"
-  },
-  "initializeCommand": [
-    "/bin/bash",
-    "-c",
-    "mkdir -m 0755 -p ${localWorkspaceFolder}/.{aws,cache,config}; mkdir -m 0755 -p ${localWorkspaceFolder}/build;",
-    "if [[ -n ${WSLENV+set} ]]; then docker volume create cccl-build; else docker volume create --driver local --opt type=none --opt device=${localWorkspaceFolder}/build --opt o=bind cccl-build fi;"
-  ],
-  "containerEnv": {
-    "SCCACHE_REGION": "us-east-2",
-    "SCCACHE_BUCKET": "rapids-sccache-devs",
-    "VAULT_HOST": "https://vault.ops.k8s.rapids.ai",
-    "HISTFILE": "${containerWorkspaceFolder}/.cache/._bash_history",
-    "DEVCONTAINER_NAME": "cuda12.0-gcc13",
-    "CCCL_CUDA_VERSION": "12.0",
-    "CCCL_HOST_COMPILER": "gcc",
-    "CCCL_HOST_COMPILER_VERSION": "13",
-    "CCCL_BUILD_INFIX": "cuda12.0-gcc13"
-  },
-  "workspaceFolder": "/home/coder/${localWorkspaceFolderBasename}",
-  "workspaceMount": "source=${localWorkspaceFolder},target=/home/coder/${localWorkspaceFolderBasename},type=bind,consistency=consistent",
-  "mounts": [
-    "source=${localWorkspaceFolder}/.aws,target=/home/coder/.aws,type=bind,consistency=consistent",
-    "source=${localWorkspaceFolder}/.cache,target=/home/coder/.cache,type=bind,consistency=consistent",
-    "source=${localWorkspaceFolder}/.config,target=/home/coder/.config,type=bind,consistency=consistent",
-    "source=cccl-build,target=/home/coder/cccl/build"
-  ],
-  "customizations": {
-    "vscode": {
-      "extensions": [
-        "llvm-vs-code-extensions.vscode-clangd",
-        "xaver.clang-format",
-        "nvidia.nsight-vscode-edition",
-        "ms-vscode.cmake-tools"
-      ],
-      "settings": {
-        "editor.defaultFormatter": "xaver.clang-format",
-        "editor.formatOnSave": true,
-        "clang-format.executable": "/usr/bin/clang-format",
-        "clangd.arguments": [
-          "--compile-commands-dir=${workspaceFolder}"
-        ],
-        "files.eol": "\n",
-        "files.trimTrailingWhitespace": true
-      }
-    }
-  },
-  "name": "cuda12.0-gcc13"
-}
diff --git a/ci/matrix.yaml b/ci/matrix.yaml
index e98ae33488..e3102f8487 100644
--- a/ci/matrix.yaml
+++ b/ci/matrix.yaml
@@ -28,15 +28,15 @@ workflows:
     # verify-codegen:
     - {jobs: ['verify_codegen'], project: 'libcudacxx'}
     # cudax has different CTK reqs:
-    - {jobs: ['build'], project: 'cudax', ctk: ['12.0', 'curr'], std: 'all', cxx: ['gcc9', 'gcc10', 'gcc11', 'gcc12']}
+    - {jobs: ['build'], project: 'cudax', ctk: ['12.0', 'curr'], std: 'all', cxx: ['gcc9', 'gcc10', 'gcc11']}
     - {jobs: ['build'], project: 'cudax', ctk: ['12.0', 'curr'], std: 'all', cxx: ['clang9', 'clang10', 'clang11', 'clang12', 'clang13']}
     - {jobs: ['build'], project: 'cudax', ctk: [        'curr'], std: 'all', cxx: ['clang14', 'clang15', 'clang16', 'clang17']}
     - {jobs: ['build'], project: 'cudax', ctk: ['12.0',       ], std: 20,    cxx: ['msvc14.36']}
     - {jobs: ['build'], project: 'cudax', ctk: [        'curr'], std: 20,    cxx: ['msvc2022']}
-    - {jobs: ['build'], project: 'cudax', ctk: ['12.0'        ], std: 17,    cxx: ['gcc13'], sm: "90"}
+    - {jobs: ['build'], project: 'cudax', ctk: ['12.0'        ], std: 17,    cxx: ['gcc12'], sm: "90"}
     - {jobs: ['build'], project: 'cudax', ctk: [        'curr'], std: 17,    cxx: ['gcc13'], sm: "90a"}
     - {jobs: ['build'], project: 'cudax', ctk: [        'curr'], std: 'all', cxx: ['gcc13', 'clang16'], cpu: 'arm64'}
-    - {jobs: ['test'],  project: 'cudax', ctk: ['12.0', 'curr'], std: 'all', cxx: ['gcc13']}
+    - {jobs: ['test'],  project: 'cudax', ctk: ['12.0', 'curr'], std: 'all', cxx: ['gcc12']}
     - {jobs: ['test'],  project: 'cudax', ctk: ['12.0'        ], std: 'all', cxx: ['clang14']}
     - {jobs: ['test'],  project: 'cudax', ctk: [        'curr'], std: 'all', cxx: ['clang18']}
     # Python jobs: