Trickles down updated dependencies across repositories


Trickles down updated dependencies across repositories through pull requests, minimizing builds and maximizing parallelism.

It requires that all projects be running this plugin, and a location where the global state can be recorded. A git connector is provided to record that state on a remote git repository.

Published for SBT 1.3.8.


The main tasks are as follows:

// Update metadata repository with this project's information

// Creates pull requests to bump versions

// Log what needs to be updated (default action of trickleCreatePullRequest)

Pull request creation can use the following input task to make sure the dependencies were properly updated. If any differing revision is found, it will fail.

trickleCheckVersion org:name:revision {...}

The following tasks/commands are provided for sbt console usage:

// Shows what needs updating

// Displays build topology graph in dot file format
show trickleBuildTopology

// Saves a dot file of the build graph topology
trickleSaveGraph <file>

// Opens build graph topology image (requires graphviz, "open")

// Resets the metadata repository to a commit, to inspect past topologies
trickleGitReset <sha1-or-tag>


On project/plugins.sbt:

addSbtPlugin("com.dcsobral" % "sbt-trickle" % "<version>")

On your build.sbt settings:

import sbttrickle.TricklePlugin.autoImport._ // not needed
import sbttrickle.metadata.OutdatedRepository
import sbttrickle.git.GitConfig
import github4s.domain.PullRequest

lazy val trickleSettings: Seq[Def.Setting[_]] = Seq(
  /* Basic configuration */

  // Centralized metadata database locator
  // mandatory
  trickleDbURI in ThisBuild := "<url>", // eg, git repository clone url

  // Information about your project repository
  // defaults to URI's path, normalized for module name rules
  trickleRepositoryName in ThisBuild := "<unique name>",

  // Information provided to PR creation and check
  // defaults to scmInfo.browseUrl or homepage
  trickleRepositoryURI in ThisBuild := "<url>",

  /* Auto bump */

  // Function which creates the autobump pull requests
  // defaults to logging what needs bumping
  trickleCreatePullRequest := (??? : OutdatedRepository => Unit),

  // Function which checks if an outdated repository has outstanding autobump pull requests
  // defaults to using trickleGithubIsAutobumpPullRequest
  trickleIsAutobumpPullRequestOpen := (??? : OutdatedRepository => Boolean),

  // Function which checks if a pull request is an autobump pull request on Github
  // defaults to always returning false, so beware
  trickleGithubIsAutobumpPullRequest := (??? : PullRequest => Boolean),

  /* Optional settings */

  // If set to true, does not update remote or create pull requests
  // defaults to not set, so it won't override trickleGitConfig values
  trickleDryMode := false,

  // Used to configure git options such as remote and authentication
  trickleGitConfig := GitConfig(trickleDbURI.value).withBranch(trickleGitBranch.?.value),

  // Branch to be used in the metadata repository
  // defaults to not set, in which case "master" is used
  trickleGitBranch := "master"


The metadata central repository can be specified with either ssh or https protocols, like git or


Authentication for https has to be in the form of user/password, provided either through the URL or through the environment variables TRICKLE_USER and TRICKLE_PASSWORD, which are used as fallback.

This is compatible with how github uses personal access tokens. User and password can be provided using the standard URL syntax of https://user:password@domain/. The password part, :password, is optional and not recommended. Instead, pass the personal access token or password through the environment variable.

It is also possible to specify user and password by setting trickleGitConfig with user and password, or creating and using a CredentialsProvider.


The remote URI can be provided either in full URL format with ssh as the protocol, or in abbreviated format like Authentication can be performed with either user and password, or using public/private keys.

User name and password can be specified in the full URL, though it is not recommended for passwords, or through the environment variables TRICKLE_USER and TRICKLE_PASSWORD, which are used as fallbacks. Alternatively , it can be passed by overriding trickleGitConfig, as seen on the HTTPS section above.

By default, ~/.ssh/identity, ~/.ssh/id_rsa and ~/.ssh/id_dsa will be looked up for public/private keys, and must have an empty passphrase. If using another file or a passphrase, override trickleGitConfig.

In all cases, the public key file must have the same name as the private key file, with .pub as extension. Newer openssh key formats, that start with BEGIN OPENSSH PRIVATE KEY, are not supported. See troubleshooting session on how to proceed in that case.


import sbttrickle.TricklePlugin.autoImport._
import sbttrickle.git.GitConfig

trickleGitConfig := {
  val remote = trickleDbURI.value
  val config =
    if (remote.startsWith("https:")) {
      (sys.env.get("GITHUB_ACTOR"), sys.env.get("GITHUB_TOKEN")) match {
        case (Some(user), Some(token)) => GitConfig(remote, user, token)
        case _                         => GitConfig(remote)
  } else {
      (sys.env.get("SSH_IDENTITY"), sys.env.get("SSH_PASSPHRASE")) match {
        case (Some(identity), Some(passphrase)) => GitConfig(remote)
          .withIdentityFile(file(identity), Some((_: File) => passphrase))
        case (Some(identity), None)             => GitConfig(remote)
        case _                                  => GitConfig(remote)

How does it work

TODO: topology example images


Authentication Issues

SSH with Public/Private Key Authentication

org.eclipse.jgit.api.errors.TransportException: <repo>: Auth fail
org.eclipse.jgit.api.errors.TransportException: <repo>: invalid privatekey: [B@26619706

The private key might be in a format not supported by jsch, the library used by sbt-trickle. From Stack Overflow:

Recent versions of OpenSSH (7.8 and newer) generate keys in new OpenSSH format by default, which start with:


JSch does not support this key format.

You can use ssh-keygen to convert the key to the classic OpenSSH format:

ssh-keygen -p -f file -m pem


The name was inspired by the Mammoth Terraces on Yellowstone National Park, but sbt-terraces just didn't evoke the right image.