diff --git a/librepomgr/buildactions/conductbuild.cpp b/librepomgr/buildactions/conductbuild.cpp
index cce22aa..379dc3c 100644
--- a/librepomgr/buildactions/conductbuild.cpp
+++ b/librepomgr/buildactions/conductbuild.cpp
@@ -342,6 +342,9 @@ void ConductBuild::run()
     }
     setupReadLock.unlock();
 
+    // use arch-specific sub-directory within cache dir
+    m_globalPackageCacheDir = m_globalPackageCacheDir % '/' + m_buildPreparation.targetArch;
+
     // fill omitted build progress configuration with defaults from global config
     if (m_autoStaging && m_buildPreparation.stagingDb.empty()) {
         reportError("Auto-staging is enabled but no staging database has been specified in build-preparation.json.");
@@ -559,8 +562,7 @@ void ConductBuild::makePacmanConfigFile(
         section.fields.erase(
             std::remove_if(section.fields.begin(), section.fields.end(), [](const AdvancedIniFile::Field &field) { return field.key == "CacheDir"; }),
             section.fields.end());
-        section.fields.emplace_back(
-            AdvancedIniFile::Field{ .key = "CacheDir", .value = m_globalPackageCacheDir % '/' + m_buildPreparation.targetArch });
+        section.fields.emplace_back(AdvancedIniFile::Field{ .key = "CacheDir", .value = m_globalPackageCacheDir });
         auto archField = section.findField("Architecture");
         if (archField == section.fieldEnd()) {
             throw std::runtime_error("pacman.conf lacks Architecture option");
diff --git a/librepomgr/serversetup.h b/librepomgr/serversetup.h
index 635da3d..4e3969f 100644
--- a/librepomgr/serversetup.h
+++ b/librepomgr/serversetup.h
@@ -120,7 +120,7 @@ struct LIBREPOMGR_EXPORT ServiceSetup : public LibPkg::Lockable {
         std::string makepkgConfigFilePath; // FIXME: not useful after all?; using config-$arch directory within chrootDir instead
         std::vector<std::string> makechrootpkgFlags;
         std::vector<std::string> makepkgFlags;
-        std::string packageCacheDir;
+        std::string packageCacheDir; // cache dir *without* architecture sub-folder (which is automatically added as needed)
         std::uint64_t packageDownloadSizeLimit = 500 * 1024 * 1024;
         std::string testFilesDir;
         BuildPresets presets;
diff --git a/librepomgr/tests/buildactions.cpp b/librepomgr/tests/buildactions.cpp
index c069639..f5028f1 100644
--- a/librepomgr/tests/buildactions.cpp
+++ b/librepomgr/tests/buildactions.cpp
@@ -124,6 +124,7 @@ void BuildActionsTests::loadBasicTestSetup()
     m_setup.building.repoAddPath = std::filesystem::absolute(testFilePath("scripts/fake_repo_add.sh"));
     m_setup.building.gpgPath = std::filesystem::absolute(testFilePath("scripts/fake_gpg.sh"));
     m_setup.building.defaultGpgKey = "1234567890";
+    m_setup.building.packageCacheDir = m_setup.building.workingDirectory + "/test-cache-dir";
     m_setup.configFilePath = std::filesystem::absolute(testFilePath("test-config/server.conf"));
 
     std::filesystem::remove_all(m_setup.workingDirectory);
@@ -536,7 +537,8 @@ void BuildActionsTests::testConductingBuild()
         readFile("building/build-data/conduct-build-test/boost/pkg/download.log"));
     CPPUNIT_ASSERT_EQUAL_MESSAGE(
         "no staging needed: updpkgsums log", "fake updatepkgsums: \n"s, readFile("building/build-data/conduct-build-test/boost/pkg/updpkgsums.log"));
-    TESTUTILS_ASSERT_LIKE("no staging needed: build log", "fake makechrootpkg: -c -u -C  -r .*chroot-dir/arch-x86_64 -l buildservice --\n"s,
+    TESTUTILS_ASSERT_LIKE("no staging needed: build log",
+        "fake makechrootpkg: -c -u -C .*building/test-cache-dir/x86_64 -r .*chroot-dir/arch-x86_64 -l buildservice --\n"s,
         readFile("building/build-data/conduct-build-test/boost/pkg/build.log"));
     TESTUTILS_ASSERT_LIKE("no staging needed: repo-add log",
         "fake repo-add: boost.db.tar.zst boost(-libs)?-1\\.73\\.0-1-x86_64.pkg.tar.zst boost(-libs)?-1\\.73\\.0-1-x86_64.pkg.tar.zst\n"s,