diff --git a/.circleci/config.yml b/.circleci/config.yml
index 48b02c27..be6666ca 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -16,7 +16,7 @@ jobs:
             wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key|apt-key add -
             apt-add-repository -y "deb http://apt.llvm.org/bionic/ llvm-toolchain-bionic-8 main"
             apt update -qq
-            apt install -y --no-install-recommends git gcc gcc-8 gcc-9 clang clang-8 clang-tidy-8 make pkg-config libncursesw5-dev libreadline-dev
+            apt install -y --no-install-recommends git gcc gcc-8 gcc-9 clang clang-8 clang-9 clang-tidy-9 make pkg-config libncursesw5-dev libreadline-dev
       - checkout
       - run:
           command: |
@@ -48,8 +48,13 @@ jobs:
             ls -l nnn
             make clean
             echo
-            echo "########## clang-tidy-8 ##########"
-            clang-tidy-8 src/* -- -I/usr/include -I/usr/include/ncursesw
+            echo "########## clang-9 ##########"
+            CC=clang-9 make strip
+            ls -l nnn
+            make clean
+            echo
+            echo "########## clang-tidy-9 ##########"
+            clang-tidy-9 src/* -- -I/usr/include -I/usr/include/ncursesw
             echo "########## checllcheck ##########"
             find plugins/ -type f -not -name "*.md" -exec shellcheck -e SC1090 {} +
 
diff --git a/src/.clang-tidy b/src/.clang-tidy
index ca009226..f94a365f 100644
--- a/src/.clang-tidy
+++ b/src/.clang-tidy
@@ -1,5 +1,5 @@
 ---
-Checks:          'clang-diagnostic-*,clang-analyzer-*,readability-*,modernize-*,bugprone-*,misc-*,-misc-unused-parameters,google-runtime-int,-llvm-header-guard,fuchsia-restrict-system-includes,-clang-analyzer-valist.Uninitialized,-clang-analyzer-security.insecureAPI.rand,-clang-analyzer-alpha.*,-readability-magic-numbers,-readability-braces-around-statements,-readability-isolate-declaration,-bugprone-narrowing-conversions'
+Checks:          'clang-diagnostic-*,clang-analyzer-*,readability-*,modernize-*,bugprone-*,misc-*,-misc-unused-parameters,google-runtime-int,-llvm-header-guard,fuchsia-restrict-system-includes,-clang-analyzer-valist.Uninitialized,-clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling,-clang-analyzer-security.insecureAPI.rand,-clang-analyzer-alpha.*,-readability-magic-numbers,-readability-braces-around-statements,-readability-isolate-declaration,-bugprone-narrowing-conversions'
 WarningsAsErrors: '*'
 HeaderFilterRegex: '.*(?<!lookup3.c)$'
 FormatStyle: 'file'