diff --git a/Jenkinsfile b/Jenkinsfile
index c2b6f92..ab4b7d5 100644
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -25,7 +25,7 @@ pipeline {
           }
           stage('tap') {
             catchError(buildResult: 'SUCCESS', stageResult: 'FAILURE') {
-              sh 'snow-chibi install retropikzel.tap'
+              sh 'snow-chibi install --impls=chibi retropikzel.tap'
               sh 'COMPILE_R7RS=chibi compile-r7rs -o tap-test-program retropikzel/tap/test.scm'
               sh './tap-test-program'
             }
@@ -53,7 +53,7 @@ pipeline {
           }
           stage('tap') {
             catchError(buildResult: 'SUCCESS', stageResult: 'FAILURE') {
-              sh 'snow-chibi install retropikzel.tap'
+              sh 'snow-chibi install --impls=sagittarius retropikzel.tap'
               sh 'COMPILE_R7RS=sagittarius compile-r7rs -o tap-test-program retropikzel/tap/test.scm'
               sh './tap-test-program'
             }
diff --git a/makings.scm b/makings.scm
index 0a3f940..bb6d80e 100644
--- a/makings.scm
+++ b/makings.scm
@@ -6,7 +6,7 @@
           "snow-chibi install retropikzel.compile-r7rs"))
       (tap
         (lambda (scheme)
-          `("snow-chibi install retropikzel.tap"
+          `(,(string-append "snow-chibi install --impls=" scheme " retropikzel.tap")
             ,(string-append "COMPILE_R7RS="
                            scheme
                            " compile-r7rs -o tap-test-program retropikzel/tap/test.scm")