pin versions and link to sample executor
diff --git a/Dockerfile b/Dockerfile
index cbe13cf..82992f4 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,15 +1,17 @@
FROM ubuntu:14.04
-
-RUN apt-get update && apt-get install -y wget git curl
-RUN apt-get update && apt-get install -y --no-install-recommends openjdk-7-jdk
-RUN apt-get update && apt-get install -y maven ant ruby rbenv make
+
RUN echo "1.554.3" > .lts-version-number
+
+RUN apt-get update && apt-get install -y wget git curl zip
+RUN apt-get update && apt-get install -y --no-install-recommends openjdk-7-jdk
+RUN apt-get update && apt-get install -y maven=3.0.5-1 ant=1.9.3-2build1 ruby rbenv make
+
RUN wget -q -O - http://pkg.jenkins-ci.org/debian-stable/jenkins-ci.org.key | sudo apt-key add -
RUN echo deb http://pkg.jenkins-ci.org/debian-stable binary/ >> /etc/apt/sources.list
RUN apt-get update && apt-get install -y jenkins
RUN mkdir -p /var/jenkins_home && chown -R jenkins /var/jenkins_home
ADD init.groovy /tmp/WEB-INF/init.groovy
-RUN apt-get install -y zip && cd /tmp && zip -g /usr/share/jenkins/jenkins.war WEB-INF/init.groovy
+RUN cd /tmp && zip -g /usr/share/jenkins/jenkins.war WEB-INF/init.groovy
USER jenkins
# VOLUME /var/jenkins_home - bind this in via -v if you want to make this persistent.
@@ -20,4 +22,5 @@
# will be used by attached slave agents:
EXPOSE 50000
-CMD ["/usr/bin/java", "-jar", "/usr/share/jenkins/jenkins.war"]
\ No newline at end of file
+
+CMD ["/usr/bin/java", "-jar", "/usr/share/jenkins/jenkins.war"]
diff --git a/README.md b/README.md
index e8daf99..26fabad 100644
--- a/README.md
+++ b/README.md
@@ -41,6 +41,8 @@
You can run builds on the master (out of the box) buf if you want to attach build slave servers: make sure you map the port: ```-p 50000:50000``` - which will be used when you connect a slave agent.
+<a href="https://registry.hub.docker.com/u/maestrodev/build-agent/">Here</a> is an example docker container you can use as a build server with lots of good tools installed - which is well worth trying.
+
# Upgrading