diff --git a/circleci.sh b/circleci.sh
index 7b64a03eb598..478869e8424d 100755
--- a/circleci.sh
+++ b/circleci.sh
@@ -114,6 +114,8 @@ coverage()
     make -j$N -C src -f posix.mak MODEL=$MODEL HOST_DMD=../_${build_path}/host_dmd clean
     make -j$N -C src -f posix.mak MODEL=$MODEL HOST_DMD=../_${build_path}/host_dmd ENABLE_COVERAGE=1
 
+    cp $build_path/dmd _${build_path}/host_dmd_cov
+    make -j1 -C src -f posix.mak MODEL=$MODEL HOST_DMD=../_${build_path}/host_dmd_cov ENABLE_COVERAGE=1 unittest
     make -j1 -C test MODEL=$MODEL ARGS="-O -inline -release" DMD_TEST_COVERAGE=1
 }
 
diff --git a/posix.mak b/posix.mak
index e0815581837e..c7d73baa1eea 100644
--- a/posix.mak
+++ b/posix.mak
@@ -5,7 +5,7 @@ ECTAGS_FILES = src/*.[chd] src/backend/*.[chd] src/root/*.[chd] src/tk/*.[chd]
 .PHONY: all clean test install auto-tester-build auto-tester-test toolchain-info
 
 all:
-	$(QUIET)$(MAKE) -C src -f posix.mak
+	$(QUIET)$(MAKE) -C src -f posix.mak all
 
 auto-tester-build: toolchain-info
 	$(QUIET)$(MAKE) -C src -f posix.mak auto-tester-build ENABLE_RELEASE=1
@@ -21,6 +21,7 @@ clean:
 	$(RM) tags
 
 test:
+	$(QUIET)$(MAKE) -C src -f posix.mak unittest
 	$(QUIET)$(MAKE) -C test -f Makefile
 
 html:
diff --git a/src/ddmd/mars.d b/src/ddmd/mars.d
index 65557fc1da0b..23f303f12762 100644
--- a/src/ddmd/mars.d
+++ b/src/ddmd/mars.d
@@ -1077,6 +1077,7 @@ Language changes listed by -transition=id:
  * Returns:
  *   Return code of the application
  */
+version(unittest) {} else
 int main()
 {
     import core.memory;
diff --git a/src/posix.mak b/src/posix.mak
index dd218305f66f..ff889d128841 100644
--- a/src/posix.mak
+++ b/src/posix.mak
@@ -459,6 +459,11 @@ $G/dmd: $(DMD_SRCS) $(ROOT_SRCS) $G/newdelete.o $G/backend.a $G/lexer.a $(STRING
 	CC="$(HOST_CXX)" $(HOST_DMD_RUN) -of$@ $(MODEL_FLAG) -vtls -J$G -J../res -L-lstdc++ $(DFLAGS) $(filter-out $(STRING_IMPORT_FILES) $(HOST_DMD_PATH) $(LEXER_ROOT),$^)
 endif
 
+$G/dmd-unittest: $(DMD_SRCS) $(ROOT_SRCS) $G/newdelete.o $G/lexer.a $(G_GLUE_OBJS) $(G_OBJS) $(STRING_IMPORT_FILES) $(HOST_DMD_PATH)
+	CC=$(HOST_CXX) $(HOST_DMD_RUN) -of$@ $(MODEL_FLAG) -vtls -J$G -J../res -L-lstdc++ $(DFLAGS) -g -unittest -main $(filter-out $(STRING_IMPORT_FILES) $(HOST_DMD_PATH),$^)
+
+unittest: $G/dmd-unittest
+	$<
 
 clean:
 	rm -R $(GENERATED)