diff --git a/kernel.spec b/kernel.spec
index f68a171..7657eaa 100644
--- a/kernel.spec
+++ b/kernel.spec
@@ -99,6 +99,12 @@
 # and it has not been adapted for kernel 5.10 (is not buildable)
 %bcond_with binary_shredder
 
+# compress modules with zstd (zstd is good compression and fast decompression)
+%bcond_without compress_modules
+# Spend more resources on compression, but make resulting size less;
+# decompression speed will not be affected.
+%define zstd_cmd zstd -q --format=zstd --ultra -22
+
 # Kernel flavour
 %if %{with nickel}
 %define flavour		nickel
@@ -162,9 +168,6 @@
 %define build_cpupower		0
 %endif
 
-
-# compress modules with xz
-%define build_modxz		1
 # End of user definitions
 
 # buildtime flags
@@ -173,19 +176,17 @@
 %{?_without_debug: %global build_debug 0}
 %{?_without_perf: %global build_perf 0}
 %{?_without_cpupower: %global build_cpupower 0}
-%{?_without_modxz: %global build_modxz 0}
 
 %{?_with_doc: %global build_doc 1}
 %{?_with_devel: %global build_devel 1}
 %{?_with_debug: %global build_debug 1}
 %{?_with_perf: %global build_perf 1}
 %{?_with_cpupower: %global build_cpupower 1}
-%{?_with_modxz: %global build_modxz 1}
 
-%if %{build_modxz}
-%define kmod_suffix .xz
+%if %{with compress_modules}
+%define kmod_suffix .zst
 %else
-%define kmod_suffix .gz
+%define kmod_suffix %{nil}
 %endif
 
 %if !%{build_debug}
@@ -402,6 +403,10 @@ BuildRequires: kernel-source-rosa-test-suite
 BuildRequires: ccache
 %endif
 
+%if %{with compress_modules}
+BuildRequires: zstd
+%endif
+
 # might be useful too:
 Recommends:		microcode
 
@@ -1356,7 +1361,8 @@ popd
 install -d %{temp_boot}
 install -m 644 System.map %{temp_boot}/System.map-%{kver_full}
 install -m 644 .config %{temp_boot}/config-%{kver_full}
-xz -c Module.symvers > %{temp_boot}/symvers-%{kver_full}.xz
+%{zstd_cmd} Module.symvers
+install -m 644 Module.symvers.zst %{temp_boot}/symvers-%{kver_full}.zst
 
 %ifarch %{armx}
 %make_build ARCH=arm64 V=1 INSTALL_DTBS_PATH=%{temp_boot}/dtb-%{kver_full} dtbs_install
@@ -1503,7 +1509,7 @@ kernel_files=../kernel_files.%{flavour}
 
 cat > $kernel_files <<EOF
 %{_bootdir}/System.map-%{kver_full}
-%{_bootdir}/symvers-%{kver_full}.xz
+%{_bootdir}/symvers-%{kver_full}.zst
 %{_bootdir}/config-%{kver_full}
 %{_bootdir}/vmlinuz-%{kver_full}
 %ifarch %{armx}
@@ -1591,10 +1597,9 @@ fi
 rm -f %{certs_verify_tmp}
 
 # compressing modules
-%if %{build_modxz}
-find %{target_modules} -name "*.ko" | %kxargs xz -6e
-%else
-find %{target_modules} -name "*.ko" | %kxargs gzip -9
+%if %{with compress_modules}
+# -T1 (one thread) because we run multiple zstd processes by xargs
+find %{target_modules} -name "*.ko" | %kxargs %{zstd_cmd} --rm -T1
 %endif
 
 pushd %{target_modules}