diff --git a/Dockerfile b/Dockerfile
index 5976915bc7ec1a3c2a03187841c69f0207392634..13642de1a74e1dbb428725af259e7edc6c0a9de6 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -125,6 +125,12 @@ RUN pip3.6 --no-cache-dir install pylint pytest astroid isort
 RUN pip3.7 --no-cache-dir install pylint pytest astroid isort
 RUN pip --no-cache-dir install pylint pytest astroid isort LinkChecker
 
+# for coverage
+RUN pip3 --no-cache-dir install coverage
+RUN pip3.6 --no-cache-dir install coverage
+RUN pip3.7 --no-cache-dir install coverage
+RUN pip --no-cache-dir install coverage
+
 COPY ./python/requirements.txt /root/
 RUN pip3 --no-cache-dir install -r /root/requirements.txt
 RUN pip3.6 --no-cache-dir install -r /root/requirements.txt
diff --git a/cmake/coveralls.cmake b/cmake/coveralls.cmake
index ca1471cabb57c0795ee193493d2e60bb5bd9e1cc..c0e96e28775f910d02e8c9d913fc3906d93291e0 100644
--- a/cmake/coveralls.cmake
+++ b/cmake/coveralls.cmake
@@ -62,7 +62,6 @@ function(code_coverage _COVERAGE_SRCS _COVERALLS_UPLOAD _CMAKE_SCRIPT_PATH)
 endfunction()
 
 if(WITH_COVERAGE)
-    set(CMAKE_BUILD_TYPE "Debug")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g -O0 -fprofile-arcs -ftest-coverage")
     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -g -O0 -fprofile-arcs -ftest-coverage")