diff --git a/cmd/image-builder/main_test.go b/cmd/image-builder/main_test.go
index 90cb4c7..fd0b714 100644
--- a/cmd/image-builder/main_test.go
+++ b/cmd/image-builder/main_test.go
@@ -753,7 +753,7 @@ func TestProgressFromCmd(t *testing.T) {
 	}
 }
 
-func TestManifestExtraRepo(t *testing.T) {
+func TestManifestExtraRepos(t *testing.T) {
 	if testing.Short() {
 		t.Skip("manifest generation takes a while")
 	}
@@ -776,25 +776,38 @@ func TestManifestExtraRepo(t *testing.T) {
         [[packages]]
         name = "dummy"
 `
-	restore := main.MockOsArgs([]string{
-		"manifest",
-		"qcow2",
-		"--distro=centos-9",
-		fmt.Sprintf("--extra-repo=file://%s", localRepoDir),
-		"--blueprint", makeTestBlueprint(t, pkgHelloBlueprint),
-	})
-	defer restore()
+	nativeArch := arch.Current()
+	// setup test for cross-arch, if we happen to run on the
+	// cross arch already just pick a different arch
+	crossArch := arch.ARCH_AARCH64
+	if arch.Current() == arch.ARCH_AARCH64 {
+		crossArch = arch.ARCH_X86_64
+	}
 
-	var fakeStdout bytes.Buffer
-	restore = main.MockOsStdout(&fakeStdout)
-	defer restore()
+	for _, arch := range []arch.Arch{nativeArch, crossArch} {
+		t.Run(arch.String(), func(t *testing.T) {
+			restore := main.MockOsArgs([]string{
+				"manifest",
+				"qcow2",
+				"--distro=centos-9",
+				fmt.Sprintf("--arch=%s", arch),
+				fmt.Sprintf("--extra-repo=file://%s", localRepoDir),
+				"--blueprint", makeTestBlueprint(t, pkgHelloBlueprint),
+			})
+			defer restore()
 
-	err = main.Run()
-	require.NoError(t, err)
+			var fakeStdout bytes.Buffer
+			restore = main.MockOsStdout(&fakeStdout)
+			defer restore()
 
-	// our local repo got added
-	assert.Contains(t, fakeStdout.String(), `"path":"dummy-1.0.0-0.noarch.rpm"`)
-	assert.Contains(t, fakeStdout.String(), fmt.Sprintf(`"url":"file://%s"`, localRepoDir))
+			err = main.Run()
+			require.NoError(t, err)
+
+			// our local repo got added
+			assert.Contains(t, fakeStdout.String(), `"path":"dummy-1.0.0-0.noarch.rpm"`)
+			assert.Contains(t, fakeStdout.String(), fmt.Sprintf(`"url":"file://%s"`, localRepoDir))
+		})
+	}
 }
 
 func TestManifestOverrideRepo(t *testing.T) {
diff --git a/cmd/image-builder/repos.go b/cmd/image-builder/repos.go
index 67b45a4..9a35731 100644
--- a/cmd/image-builder/repos.go
+++ b/cmd/image-builder/repos.go
@@ -6,7 +6,6 @@ import (
 	"net/url"
 
 	"github.com/osbuild/images/data/repositories"
-	"github.com/osbuild/images/pkg/arch"
 	"github.com/osbuild/images/pkg/reporegistry"
 	"github.com/osbuild/images/pkg/rpmmd"
 )
@@ -71,21 +70,24 @@ func newRepoRegistryImpl(dataDir string, extraRepos []string) (*reporegistry.Rep
 		return nil, err
 	}
 
-	// XXX: this should probably go into manifestgen.Options as
-	// a new Options.ExtraRepoConf eventually (just like OverrideRepos)
+	// Add extra repos to all architecture. We support
+	// cross-building but at this level here we don't know yet
+	// what manifests will be generated so we must (for now)
+	// rely on the user to DTRT with extraRepos.
+	//
+	// XXX: this should probably go into manifestgen.Options as a
+	// new Options.ExtraRepoConf eventually (just like
+	// OverrideRepos)
 	repoConf, err := parseRepoURLs(extraRepos, "extra")
 	if err != nil {
 		return nil, err
 	}
-	// Only add extra repos for the host architecture. We do not support
-	// cross-building (yet) so this is fine. Once we support cross-building
-	// this needs to move (probably into manifestgen) because at this
-	// level we we do not know (yet) what manifest we will generate.
-	myArch := arch.Current().String()
 	for _, repoArchConfigs := range conf {
-		archCfg := repoArchConfigs[myArch]
-		archCfg = append(archCfg, repoConf...)
-		repoArchConfigs[myArch] = archCfg
+		for arch := range repoArchConfigs {
+			archCfg := repoArchConfigs[arch]
+			archCfg = append(archCfg, repoConf...)
+			repoArchConfigs[arch] = archCfg
+		}
 	}
 
 	return reporegistry.NewFromDistrosRepoConfigs(conf), nil