diff --git a/tests/wscript b/tests/wscript
index cf28718..ed4eb19 100644
--- a/tests/wscript
+++ b/tests/wscript
@@ -1,6 +1,6 @@
 # -*- Mode: python; py-indent-offset: 4; indent-tabs-mode: nil; coding: utf-8; -*-
 """
-Copyright (c) 2014-2020,  Regents of the University of California,
+Copyright (c) 2014-2023,  Regents of the University of California,
                           Arizona Board of Regents,
                           Colorado State University,
                           University Pierre & Marie Curie, Sorbonne University,
@@ -41,10 +41,10 @@
 
         for module in ['core', 'daemon', 'rib', 'tools']:
             # main() for the module
-            bld.objects(target='unit-tests-%s-main' % module,
+            bld.objects(target=f'unit-tests-{module}-main',
                         source='main.cpp',
                         use='BOOST',
-                        defines=['BOOST_TEST_MODULE=NFD %s' % module.capitalize()])
+                        defines=[f'BOOST_TEST_MODULE=NFD {module.capitalize()}'])
 
             subdir = 'daemon/rib' if module == 'rib' else module
             node = bld.path.find_dir(subdir)
@@ -66,10 +66,10 @@
 
             objmod = 'daemon' if module == 'rib' else module
             # unit-tests binary for the module
-            bld.program(name='unit-tests-%s' % module,
-                        target='../unit-tests-%s' % module,
+            bld.program(name=f'unit-tests-{module}',
+                        target=f'{top}/unit-tests-{module}',
                         source=src,
-                        use='%s-objects tests-common unit-tests-%s-main' % (objmod, module),
+                        use=f'{objmod}-objects tests-common unit-tests-{module}-main',
                         defines=[tmpdir],
                         install_path=None)