The madness vendoring utility for Golang programs.


manul can be obtained using go get:

go get

What's the reason for yet another utility?

Because all other vendor utilities suffer from the following:

  • Some wrap the go binary and spoof the GOPATH env variable.
    You will have a non-go-gettable project which needs additional
    software in order to compile and run;

  • Some copy the source code of dependencies into the vendor directory:

    • It will be nearly impossible to find anything using GitHub Search,
      because you will get many false-positive results;
    • Updating dependencies will require manual intervention and committing
      a lot of modified lines straight into the main repo;
    • You will not be able to tell what version of dependency your project is
      using will by looking at repository; you have to keep versions in the
      additional ambiguous file with vendors associated with commits.
  • Various architecture problems:

    • Impossible to update all or specific vendored dependencies;
    • Impossible to rollback vendored dependencies to specific version;
    • Impossible to remove unused vendored dependencies;
    • Impossible to lock version of vendored dependency.


We all love git, it's a very powerful instrument. Why don't we use its
power for vendoring dependencies using an awesome feature, which is called
git submodule?

With git submodule you will have a git repository for each dependency.
They can be managed in the same way as main project by git.


  • No need for additional software for building/running your Go project;

  • No need for additional JSON/TOML/YAML file for storing dependencies;

  • Update vendored dependencies directly from remote origins;

  • Rollback changes in dependencies;

  • Go-gettable

git submodule might look like a Silver Bullet, but it's still clumsy to
work with manually. We want to have a powerful yet simple interface for
vendoring dependencies using this technology.

manul can do it for us.


Who needs a documentation when there are GIFs?

First of all, we should request dependencies which we have in our project.
To do this, just run manul with -Q (query) flag. It will output all the
project imports (dependencies), like this:

first query

For example, we have six dependencies, let's lock versions of critical
dependencies by adding submodules: in our case it's zhash and blackfriday

For locking versions (installing dependencies) we should use -I (install)
flag and specify dependencies, which we wish to install:

install two dependencies

After installation we can have a look for vendored and non-vendored
dependencies by using flag -Q. After previous step we should see git commits
along with two already vendored dependencies (zhash and blackfriday):

query after install

Let's install submodules for remaining dependencies, go the limit! Just run
manul with flag -I without specifying any dependencies, manul will
install all detected dependencies with skipping already vendored:

install all dependencies

Wow, that was crazy! Now, to update some vendored dependencies, for example,
docopt-go package, manul should be invoked with the flag -U and import path

update docopt

manul can be used to remove specified submodules of vendored dependencies
by using -R (remove) flag and specifying dependencies import path:


By the way, manul can detect and remove unused vendored dependencies using -C
(clean) flag:

unused dependencies

manul can also get you a specific version of a dependency by using a commit-ish, for example:

  • manul -I will install foo at the specified commit
  • manul -U will update it to this-tag version.

Let's summarize:

  • -I [<dependency>...] - install git submodules for specified/all dependencies;
  • -U [<dependency>...] - update specified/all already vendored dependencies;
  • -R [<dependency>...] - remove git submodules for specified/all dependencies;
  • -Q [<dependency>...] - list all used dependencies;
  • -C - detect and remove all git submodules for unused vendored dependencies.

You can see similar help message by passing -h or --help flag.