diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index d15adad01ad2999f891bc94fbdc507b3861da2db..5f1bd3565fc17e1835fa4b420118603467266cc6 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -5,17 +5,16 @@
 # files implicitly passed between jobs or stages, only artifacts and maybe
 # cache (depends on configuration).
 
+image: alpine:3.6
+
 before_script:
   - case "$CI_BUILD_NAME" in
-      *-clang) export CXX=clang++ EXTRA_PKGS="$EXTRA_PKGS clang@edge2";;
+      *-clang) export CXX=clang++ EXTRA_PKGS="$EXTRA_PKGS clang";;
       *) export CXX=g++;;
     esac
   - export JOBS=$(grep -c processor /proc/cpuinfo)
-  # XXX: Remove after Alpine v3.6 is released and rename tclap-dev@edge to tclap-dev and clang@edge2 to clang.
-  - echo '@edge http://repository.fit.cvut.cz/mirrors/alpine/edge/community' >> /etc/apk/repositories
-  - echo '@edge2 http://repository.fit.cvut.cz/mirrors/alpine/edge/main' >> /etc/apk/repositories
   - apk add --no-cache build-base bash libexecinfo-dev
-        cppunit-dev libxml2-dev tclap-dev@edge $EXTRA_PKGS
+        cppunit-dev libxml2-dev tclap-dev $EXTRA_PKGS
 
 
 #==========  Stage build  ==========