diff --git a/libthai.changes b/libthai.changes
index bc3515c..59bb280 100644
--- a/libthai.changes
+++ b/libthai.changes
@@ -1,3 +1,13 @@
+-------------------------------------------------------------------
+Mon Mar  5 15:40:22 UTC 2018 - jengelh@inai.de
+
+- Fix SRPM group. Update descriptions.
+
+-------------------------------------------------------------------
+Wed Feb 28 16:36:34 UTC 2018 - dimstar@opensuse.org
+
+- Modernize spec-file by calling spec-cleaner
+
 -------------------------------------------------------------------
 Wed Nov  1 08:59:46 UTC 2017 - fezhang@suse.com
 
diff --git a/libthai.spec b/libthai.spec
index bdaf097..a4a1545 100644
--- a/libthai.spec
+++ b/libthai.spec
@@ -1,7 +1,7 @@
 #
 # spec file for package libthai
 #
-# Copyright (c) 2017 SUSE LINUX GmbH, Nuernberg, Germany.
+# Copyright (c) 2018 SUSE LINUX GmbH, Nuernberg, Germany.
 #
 # All modifications and additions to the file contributed by third parties
 # remain the property of their copyright owners, unless otherwise agreed
@@ -20,64 +20,59 @@ Name:           libthai
 Version:        0.1.27
 Release:        0
 Summary:        Thai Language Support Routines
-License:        LGPL-2.1+
-Group:          System/Libraries
+License:        LGPL-2.1-or-later
+Group:          Development/Libraries/C and C++
 Url:            http://linux.thai.net/plone/TLWG/libthai/
 Source:         https://linux.thai.net/pub/thailinux/software/libthai/%{name}-%{version}.tar.xz
 Source99:       baselibs.conf
 BuildRequires:  libdatrie-devel
-BuildRequires:  pkg-config
-BuildRoot:      %{_tmppath}/%{name}-%{version}-build
+BuildRequires:  pkgconfig
 
 %description
-LibThai is a set of Thai language support routines aimed to ease
-developers' tasks to incorporate Thai language support in their
-applications. It includes important Thai-specific functions, such as
-word breaking, input and output methods, and basic character and string
-support.
+LibThai is a set of Thai language support routines to aid
+incorporation of Thai language support into applications. It includes
+important Thai-specific functions, such as word breaking, input and
+output methods, and basic character and string support.
 
 %package -n libthai0
 Summary:        Thai Language Support Routines
 # SLPP applied since version 0.1.15.
-Group:          System/Libraries
-Provides:       libthai = %{version}
-Obsoletes:      libthai < %{version}
 # libthai needs the data to run, but the data is not parallel-installable,
 # hence the >= instead of =. We just hope the data format will stay the same in
 # the future.
+Group:          System/Libraries
 Requires:       libthai-data >= %{version}
+Provides:       libthai = %{version}
+Obsoletes:      libthai < %{version}
 
 %description -n libthai0
-LibThai is a set of Thai language support routines aimed to ease
-developers' tasks to incorporate Thai language support in their
-applications. It includes important Thai-specific functions, such as
-word breaking, input and output methods, and basic character and string
-support.
+LibThai is a set of Thai language support routines to aid
+incorporation of Thai language support into applications. It includes
+important Thai-specific functions, such as word breaking, input and
+output methods, and basic character and string support.
 
 %package data
-Summary:        Thai Language Support Routines - Data files
+Summary:        Data files for the Thai language support library
 Group:          System/Libraries
 
 %description data
-LibThai is a set of Thai language support routines aimed to ease
-developers' tasks to incorporate Thai language support in their
-applications. It includes important Thai-specific functions, such as
-word breaking, input and output methods, and basic character and string
-support.
+LibThai is a set of Thai language support routines to aid
+incorporation of Thai language support into applications. It includes
+important Thai-specific functions, such as word breaking, input and
+output methods, and basic character and string support.
 
 This package contains the data files for libthai.
 
 %package devel
-Summary:        Thai Language Support Routines (development files)
+Summary:        Development files for the Thai language support library
 Group:          Development/Languages/C and C++
 Requires:       libthai0 = %{version}
 
 %description devel
-LibThai is a set of Thai language support routines aimed to ease
-developers' tasks to incorporate Thai language support in their
-applications. It includes important Thai-specific functions, such as
-word breaking, input and output methods, and basic character and string
-support.
+LibThai is a set of Thai language support routines to aid
+incorporation of Thai language support into applications. It includes
+important Thai-specific functions, such as word breaking, input and
+output methods, and basic character and string support.
 
 This package contains headers and libraries required for developing
 software using libthai.
@@ -86,30 +81,23 @@ software using libthai.
 %setup -q
 
 %build
-%configure --disable-static --with-pic
+%configure --disable-static
 make %{?_smp_mflags}
 
 %install
 %make_install
-find %{buildroot}%{_libdir} -type f -name "*.la" -delete -print
-
-%clean
-rm -rf %{buildroot}
+find %{buildroot} -type f -name "*.la" -delete -print
 
 %post -n libthai0 -p /sbin/ldconfig
-
 %postun -n libthai0 -p /sbin/ldconfig
 
 %files -n libthai0
-%defattr(-,root,root)
 %{_libdir}/libthai.so.*
 
 %files data
-%defattr(-, root, root)
 %{_datadir}/libthai/
 
 %files devel
-%defattr(-,root,root)
 %{_includedir}/thai/
 %{_libdir}/libthai.so
 %{_libdir}/pkgconfig/*.pc