diff --git a/lib/worker_multibuild.py b/lib/worker_multibuild.py
index 397b077..8aa55ea 100644
--- a/lib/worker_multibuild.py
+++ b/lib/worker_multibuild.py
@@ -61,12 +61,16 @@ def list_jobs(directory=".buildbot"):
     results = []
     files = ["Dockerfile", "build.sh", "test.sh"]
     for item in listdir(directory):
+        flag = False
         for file in files:
             filepath = join(directory, item, file)
-            if islink(filepath) and not exists(filepath):
-                continue
-            if exists(join(directory, item, 'Dockerfile')) or exists(join(directory, item, 'build.sh')) or exists(join(directory, item, 'test.sh')):
-                results.append(filepath)
+            if islink(filepath) or not isfile(filepath):
+                flag = True
+                break
+        if flag:
+            continue    
+        if (exists(join(directory, item, 'Dockerfile')) and exists(join(directory, item, 'build.sh'))) or exists(join(directory, item, 'test.sh')):
+            results.append(item)
     return results
 
 
@@ -82,7 +86,7 @@ def _get_dockerfile_contents(jobname):
         res = ""
         inside_allowed_command = False
         for line in contents:
-            if re.match(r"(?m)^(FROM|RUN).*$", line):
+            if re.match(r"(?m)^(FROM|RUN|ENV).*$", line):
                 inside_allowed_command = True
             if inside_allowed_command:
                 res += line
diff --git a/multibuild.py b/multibuild.py
index 39210f4..4aa011e 100644
--- a/multibuild.py
+++ b/multibuild.py
@@ -19,6 +19,9 @@ from buildbot.plugins import steps, util
 from .lib.renderers import *
 
 
+os_codename='bionic'
+
+
 def find_artifacts(directory="out"):
     """
     find artifacts (any file) in a directory
@@ -43,18 +46,17 @@ def add_parent_step(build_factory):
         name="download worker",
         command=["wget", "-O", "https://git.bitmessage.org/Bitmessage/buildbot_multibuild/raw/branch/master/lib/worker_multibuild.py", join(getenv['HOME'], '.local/bin/worker_multibuild.py')]
     ))
-
+    
     build_factory.addStep(
         steps.ShellCommand(
             name="Execute worker script",
             command=[
                 "python3",
                 join(getenv['HOME'], '.local/bin/worker_multibuild.py'),
-                util.Interpolate("%(prop:jobname)s"),
                 util.Property('repository'),
                 util.Property('branch'),
-                "https://buildbot.bitmessage.org",
-                util.Interpolate("%(prop:os_codename)s"),
+                util.getURLForBuild(util, util.Property("builderid"), util.Property("buildnumber")),
+                os_codename,
             ],
         )
     )