From 9ff3db876fe5df1a15060cfc8387cf3b785296e6 Mon Sep 17 00:00:00 2001
From: "Hans J. Johnson" <hans-johnson@uiowa.edu>
Date: Tue, 14 Apr 2026 16:10:05 -0500
Subject: [PATCH 1/2] =?UTF-8?q?COMP:=20Fix=20lint=20workflow=20=E2=80=94?=
 =?UTF-8?q?=20action=20default=20branch=20renamed=20to=20main?=
MIME-Version: 1.0
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ITKClangFormatLinterAction repo renamed its default branch from
`master` to `main`. The lint workflow referenced `@master` which
no longer resolves.
---
 .github/workflows/lint.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index 4c2d54586..ee5e0c67d 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -14,7 +14,7 @@ jobs:
         fetch-depth: 0
 
     - name: Lint C++
-      uses: InsightSoftwareConsortium/ITKClangFormatLinterAction@master
+      uses: InsightSoftwareConsortium/ITKClangFormatLinterAction@main
 
     - name: Set up Python
       uses: actions/setup-python@v5

From 664d8e0308edf80b9cd324c52ddcab5e53946199 Mon Sep 17 00:00:00 2001
From: "Hans J. Johnson" <hans-johnson@uiowa.edu>
Date: Tue, 14 Apr 2026 16:20:00 -0500
Subject: [PATCH 2/2] COMP: Cache ExternalData and build against ITK main

Add GitHub Actions cache for ExternalData object stores in all three
build jobs (build-test-cxx, build-test-python-superbuild,
build-test-documentation). This avoids re-downloading 563 CID-addressed
test data files on every CI run.

Also update itk-git-tag from v6.0a02 to main to pick up CI fixes
merged after that tag (ccache, dashboard script, etc.).
---
 .github/workflows/build-test-publish.yml | 26 +++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/build-test-publish.yml b/.github/workflows/build-test-publish.yml
index c5dde2ac8..c40e8da70 100644
--- a/.github/workflows/build-test-publish.yml
+++ b/.github/workflows/build-test-publish.yml
@@ -3,7 +3,7 @@ name: Build, test, publish
 on: [push,pull_request]
 
 env:
-  itk-git-tag: "v6.0a02"
+  itk-git-tag: "main"
 
 jobs:
   build-test-cxx:
@@ -57,6 +57,14 @@ jobs:
           cd ITK
           git checkout ${{ env.itk-git-tag }}
 
+      - name: Restore ExternalData cache
+        uses: actions/cache@v4
+        with:
+          path: ${{ github.workspace }}/../bld/ExternalData/Objects
+          key: externaldata-v1-${{ hashFiles('Ex/src/**/*.cid') }}
+          restore-keys: |
+            externaldata-v1-
+
       - name: Build ITK
         if: matrix.os != 'windows-2022'
         run: |
@@ -169,6 +177,14 @@ jobs:
       - name: Get specific version of CMake, Ninja
         uses: lukka/get-cmake@v3.24.2
 
+      - name: Restore ExternalData cache
+        uses: actions/cache@v4
+        with:
+          path: ${{ github.workspace }}/../bld/ExternalData/Objects
+          key: externaldata-superbuild-v1-${{ matrix.os }}-${{ hashFiles('Ex/src/**/*.cid') }}
+          restore-keys: |
+            externaldata-superbuild-v1-${{ matrix.os }}-
+
       - name: Fetch CTest driver script
         run: |
           curl -L https://raw.githubusercontent.com/InsightSoftwareConsortium/ITKSphinxExamples/dashboard/itkexamples_common.cmake -O
@@ -308,6 +324,14 @@ jobs:
           SITE_PACKAGES_DIR=$(python3 "-c" "from distutils import sysconfig; print(sysconfig.get_python_lib())")
           sed -i "6559d" ${SITE_PACKAGES_DIR}/sphinx/domains/cpp.py
 
+      - name: Restore ExternalData cache
+        uses: actions/cache@v4
+        with:
+          path: ${{ github.workspace }}/../bld/ExternalData/Objects
+          key: externaldata-docs-v1-${{ hashFiles('Ex/src/**/*.cid') }}
+          restore-keys: |
+            externaldata-docs-v1-
+
       - name: Fetch CTest driver script
         run: |
           curl -L https://raw.githubusercontent.com/InsightSoftwareConsortium/ITKSphinxExamples/dashboard/itkexamples_common.cmake -O