diff --git a/Telegram/build/docker/centos_env/Dockerfile b/Telegram/build/docker/centos_env/Dockerfile
index eeb5cb87b5..50ac9bfb9b 100644
--- a/Telegram/build/docker/centos_env/Dockerfile
+++ b/Telegram/build/docker/centos_env/Dockerfile
@@ -868,6 +868,8 @@ COPY --from=breakpad ${LibrariesPath}/breakpad breakpad
 COPY --from=breakpad ${LibrariesPath}/breakpad-cache /
 COPY --from=webrtc ${LibrariesPath}/tg_owt tg_owt
 
+RUN yum -y install llvm-toolset-7.0 llvm-toolset-7.0-clang-devel llvm-toolset-7.0-llvm-devel
+
 WORKDIR ../tdesktop
 VOLUME [ "/usr/src/tdesktop" ]
 CMD [ "/usr/src/tdesktop/Telegram/build/docker/centos_env/build.sh" ]
diff --git a/Telegram/build/docker/centos_env/build.sh b/Telegram/build/docker/centos_env/build.sh
index c965b47d28..90615e3238 100755
--- a/Telegram/build/docker/centos_env/build.sh
+++ b/Telegram/build/docker/centos_env/build.sh
@@ -1,10 +1,10 @@
-#!/bin/bash
+#!/usr/bin/scl enable llvm-toolset-7.0 -- scl enable devtoolset-9 -- bash
 
 cd Telegram
-scl enable devtoolset-9 -- ./configure.sh "$@"
+./configure.sh "$@"
 
 if [ -n "$DEBUG" ]; then
-	scl enable devtoolset-9 -- cmake3 --build ../out/Debug -j$(nproc)
+	cmake3 --build ../out/Debug -j$(nproc)
 else
-	scl enable devtoolset-9 -- cmake3 --build ../out/Release -j$(nproc)
+	cmake3 --build ../out/Release -j$(nproc)
 fi
diff --git a/snap/snapcraft.yaml b/snap/snapcraft.yaml
index 7ea662299b..b5147e9589 100644
--- a/snap/snapcraft.yaml
+++ b/snap/snapcraft.yaml
@@ -85,6 +85,7 @@ parts:
     build-environment:
       - LD_LIBRARY_PATH: $SNAPCRAFT_STAGE/usr/lib/$SNAPCRAFT_ARCH_TRIPLET:$LD_LIBRARY_PATH
     build-packages:
+      - clang
       - python
       - libasound2-dev
       - libglib2.0-dev