diff --git a/.forgejo/workflows/build.yml b/.forgejo/workflows/build.yml
index 84f51ffd..1d60106e 100644
--- a/.forgejo/workflows/build.yml
+++ b/.forgejo/workflows/build.yml
@@ -114,3 +114,36 @@ jobs:
             fi
             echo "Uploaded ${FILENAME} (HTTP ${HTTP_CODE})"
           done
+
+      - name: Prune old releases
+        run: |
+          TAG_PREFIX="${{ github.ref_name == 'main' && 'v6' || 'v6.*-beta' }}"
+          CURRENT_ID="${{ steps.create_release.outputs.id }}"
+          echo "Keeping release ${CURRENT_ID}, pruning older ${TAG_PREFIX} releases..."
+          PAGE=1
+          while true; do
+            RELEASES=$(curl -s "${FORGEJO_URL}/api/v1/repos/${{ github.repository }}/releases?limit=50&page=${PAGE}" \
+              -H "Authorization: token ${{ secrets.RELEASE_TOKEN }}")
+            COUNT=$(echo "$RELEASES" | python3 -c "import sys,json; print(len(json.load(sys.stdin)))" 2>/dev/null || echo 0)
+            [ "$COUNT" = "0" ] && break
+            echo "$RELEASES" | python3 -c "
+          import sys, json, fnmatch
+          for r in json.load(sys.stdin):
+              rid = r['id']
+              tag = r['tag_name']
+              if rid == ${CURRENT_ID}:
+                  continue
+              if fnmatch.fnmatch(tag, '${TAG_PREFIX}*'):
+                  print(f'{rid} {tag}')
+          " | while read -r RID RTAG; do
+              echo "Deleting release ${RTAG} (id=${RID})"
+              curl -s -o /dev/null -X DELETE \
+                "${FORGEJO_URL}/api/v1/repos/${{ github.repository }}/releases/${RID}" \
+                -H "Authorization: token ${{ secrets.RELEASE_TOKEN }}"
+              curl -s -o /dev/null -X DELETE \
+                "${FORGEJO_URL}/api/v1/repos/${{ github.repository }}/tags/${RTAG}" \
+                -H "Authorization: token ${{ secrets.RELEASE_TOKEN }}"
+            done
+            PAGE=$((PAGE + 1))
+          done
+          echo "Prune complete"