diff --git a/step.spec b/step.spec
index 06bac19..48f7c75 100644
--- a/step.spec
+++ b/step.spec
@@ -1,5 +1,5 @@
 Name:          step
-Version:       20.12.2
+Version:       20.12.3
 Release:       1mamba
 Summary:       Interactive Physical Simulator
 Group:         Graphical Desktop/Applications/Educational
@@ -51,7 +51,6 @@ BuildRequires: libstdc++6-devel
 BuildRequires: libqalculate-devel >= 2.6.2-1mamba
 BuildRequires: libeigen2-devel
 BuildRequires: cmake
-BuildRoot:     %{_tmppath}/%{name}-%{version}-root
 
 %description
 Step is an interactive physical simulator.
@@ -132,6 +131,9 @@ exit 0
 #ChangeLog README TODO
 
 %changelog
+* Sat Mar 06 2021 Automatic Build System <autodist@mambasoft.it> 20.12.3-1mamba
+- automatic version update by autodist
+
 * Fri Feb 05 2021 Automatic Build System <autodist@mambasoft.it> 20.12.2-1mamba
 - automatic version update by autodist