diff --git a/Jenkinsfile b/Jenkinsfile
index 5eb7e32..e7c305d 100644
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -14,19 +14,20 @@ pipeline {
                 script {
                     //def implementations = sh(script: 'docker run retropikzel1/compile-r7rs:chibi sh -c "compile-r7rs --list-r7rs-schemes"', returnStdout: true).split()
                     def implementations = "chibi chicken gauche guile kawa mosh racket sagittarius stklos ypsilon".split()
+                    def DOCKERIMG = sh(script: 'make docker-image', returnStdout: true)
 
                     parallel implementations.collectEntries { implementation->
                         [(implementation): {
                                 stage("${implementation} install") {
                                     catchError(buildResult: 'SUCCESS', stageResult: 'FAILURE') {
-                                        sh "docker build --build-arg SCHEME=${implementation} --tag=foreign-c-test-${implementation} -f dockerfiles/Dockerfile.snow-chibi-install-test ."
+                                        sh "docker build --build-arg IMAGE=${DOCKERIMG} --build-arg SCHEME=${implementation} --tag=foreign-c-test-${implementation} -f dockerfiles/Dockerfile.snow-chibi-install-test ."
                                         sh "docker run -v ${WORKSPACE}:/workdir -w /workdir -t foreign-c-test-${implementation} sh -c \"timeout 120 make clean all install-jenkins SCHEME=${implementation} && cp tests/hello.scm /tmp/ && cd /tmp && SCHEME=${implementation} compile-r7rs -o hello hello.scm && timeout 120 ./hello\""
                                     }
                                 }
                                 tests.each { test ->
                                     stage("${implementation} ${test}") {
                                         catchError(buildResult: 'SUCCESS', stageResult: 'FAILURE') {
-                                            sh "docker build --build-arg SCHEME=${implementation} --tag=foreign-c-test-${implementation} -f dockerfiles/Dockerfile.test ."
+                                            sh "docker build --build-arg IMAGE=${DOCKERIMG} --build-arg SCHEME=${implementation} --tag=foreign-c-test-${implementation} -f dockerfiles/Dockerfile.test ."
                                             sh "docker run -v ${WORKSPACE}:/workdir -w /workdir -t foreign-c-test-${implementation} sh -c \"timeout 120 make SCHEME=${implementation} TEST=${test} clean test\""
                                         }
                                     }
diff --git a/Makefile b/Makefile
index 4b81db3..fcfcfce 100644
--- a/Makefile
+++ b/Makefile
@@ -6,9 +6,16 @@ VERSION=$(shell awk '/version:/{ print $$2 }' README.md )
 TEST=primitives
 SCHEME=chibi
 TMPDIR=tmp/${SCHEME}
+DOCKERIMG=${SCHEME}:head
+ifeq "${SCHEME}" "chicken"
+DOCKERIMG=${SCHEME}
+endif
 
 all: build ${TMPDIR}
 
+docker-image:
+	echo ${DOCKERIMG}
+
 build:
 	snow-chibi package \
 		--version=${VERSION} \
@@ -79,7 +86,7 @@ test-compile-r7rs-wine:
 		wine ./${TEST}.bat
 
 test-docker:
-	docker build --build-arg SCHEME=${SCHEME} --tag=foreign-c-test-${SCHEME} -f dockerfiles/Dockerfile.test .
+	docker build --build-arg IMAGE=${DOCKERIMG} --build-arg SCHEME=${SCHEME} --tag=foreign-c-test-${SCHEME} -f dockerfiles/Dockerfile.test .
 	docker run -it -v "${PWD}:/workdir" -w /workdir -t foreign-c-test-${SCHEME} sh -c "make SCHEME=${SCHEME} TEST=${TEST} test"
 
 ${TMPDIR}/test/libtest.o: tests/c-src/libtest.c
diff --git a/dockerfiles/Dockerfile.snow-chibi-install-test b/dockerfiles/Dockerfile.snow-chibi-install-test
index 9926af7..0492b61 100644
--- a/dockerfiles/Dockerfile.snow-chibi-install-test
+++ b/dockerfiles/Dockerfile.snow-chibi-install-test
@@ -1,4 +1,5 @@
 ARG SCHEME=chibi
+ARG IMAGE=chibi:head
 FROM schemers/chibi:head AS build
 RUN apt-get update && apt-get install -y \
     ca-certificates \
@@ -11,7 +12,8 @@ RUN git clone https://gitea.scheme.org/Retropikzel/compile-r7rs.git --depth=1
 RUN cd compile-r7rs --branch=retropikzel-dependency-fixes && make
 
 ARG SCHEME=chibi
-FROM schemers/${SCHEME}:head
+ARG IMAGE=chibi:head
+FROM schemers/${IMAGE}
 RUN apt-get update && apt-get install -y \
     build-essential \
     git \
diff --git a/dockerfiles/Dockerfile.test b/dockerfiles/Dockerfile.test
index 12ca3ee..a273cf6 100644
--- a/dockerfiles/Dockerfile.test
+++ b/dockerfiles/Dockerfile.test
@@ -1,4 +1,5 @@
 ARG SCHEME=chibi
+ARG IMAGE=chibi:head
 FROM schemers/chibi:head AS build
 RUN apt-get update && apt-get install -y \
     ca-certificates \
@@ -11,7 +12,8 @@ RUN git clone https://gitea.scheme.org/Retropikzel/compile-r7rs.git --depth=1
 RUN cd compile-r7rs && make
 
 ARG SCHEME=chibi
-FROM schemers/${SCHEME}:head
+ARG IMAGE=chibi:head
+FROM schemers/${IMAGE}
 RUN apt-get update && apt-get install -y \
 	build-essential \
 	git \
diff --git a/tests/primitives.scm b/tests/primitives.scm
index b4bc51c..9b258c1 100644
--- a/tests/primitives.scm
+++ b/tests/primitives.scm
@@ -1,5 +1,6 @@
 (import (scheme base)
         (scheme write)
+	(scheme read)
         (scheme char)
         (scheme file)
         (scheme process-context)
@@ -324,6 +325,8 @@
                                                    (string->c-utf8 "cat2")))
                     "con2cat2") #t)
 
+(when (file-exists? "testfile.test")
+  (delete-file "testfile.test"))
 (define-c-procedure c-fopen libc 'fopen 'pointer '(pointer pointer))
 (define output-file (c-fopen (string->c-utf8 "testfile.test")
                               (string->c-utf8 "w")))
@@ -338,8 +341,8 @@
 (debug closed-status)
 (assert equal? (= closed-status 0) #t)
 (assert equal? (file-exists? "testfile.test") #t)
-(assert equal? (string=? (with-input-from-file "testfile.test"
-                                               (lambda () (read-line)))
-                         "Hello world 1") #t)
+(define file-content (with-input-from-file "testfile.test"
+					       (lambda () (read-line))))
+(assert equal? (string=? file-content "Hello world 1") #t)
 
-(exit 0)
+(exit)