Most users should not need to build Cromwell and can use pre-built Cromwell releases.
If for some reason you require a non-release version of Cromwell or are developing new Cromwell features or fixes, the following are required to build Cromwell from source:
First start by cloning the Cromwell repository from GitHub:
$ git clone email@example.com:broadinstitute/cromwell.git
Next change into the
$ cd cromwell
If you require a specific version of Cromwell as a starting point, do the appropriate
git checkout now.
Finally build the Cromwell jar:
$ sbt assembly
sbt assembly will build the runnable Cromwell JAR in
server/target/scala-2.12/ with a name like
To build a Docker image, run:
$ sbt server/docker
This will build and tag a Docker image with a name like
If you develop Cromwell using IntelliJ IDEA, you may see the following error message in IntelliJ:
Error occurred during initialization of VM Initial heap size set to a larger value than the maximum heap size
This is caused by IntelliJ overriding the
Xmx (max heap) option in our custom
.sbtopts file to a value that's below
Xms (initial heap) value. We cannot tell IntelliJ not to do this, but we can set it to a compatible value.
Go to Preferences -> Build, Execution, Deployment -> sbt -> JVM and increase the value of
Maximum heap size, MB above our
Xms value of 2 GB. A
Maximum heap size value of
2100 MB will be sufficient.