Universal build and CI testing for Haskell packages

Version on this page:0.3.1
LTS Haskell 12.19:0.3.1
Stackage Nightly 2018-11-19:0.4.1
Latest on Hackage:0.4.1

See all snapshots packcheck appears in

BSD3 licensed by Harendra Kumar
Maintained by

Module documentation for 0.3.1


Hackage Build Status Windows Build status CircleCI Coverage Status

Quick Start


To enable CI for your repo, just copy the relevant CI config file i.e. .travis.yml, appveyor.yml, or .circleci/config.yml to your package repo, add your repo to travis/appveyor/circleci and CI should just work for most packages. Uncomment the relevant lines in the CI config files to enable CI for more configs. Just modify some environment variables in the configs to control everything about the build.

Local Machine

For local use, copy to your local machine (Linux/OSX/Windows), put it in your PATH, and run it from your package directory. You can pass the same evironment variables that are used in CI files to run the exact same tests locally. Usage is as simple as:

$ cabal-new
$ cabal
$ stack

Some Key Points

  • If a CI build fails just copy and paste the command printed in the log and the same build runs on the local machine so that you can debug quickly.
  • To send coverage info to just uncomment a line in your .travis.yml.
  • If you are using hvr-ghc PPA, just use TOOLS_DIR=/opt or the path where it is installed, and you can use all the ghc/cabal versions available, automatically.
  • Conveniently control all aspects of build through command line or environment variables, including tool options or whether to enable benchmarks, haddock, coverage, install test etc. It is a very powerful tool, can do whatever you can imagine, see full reference at the end.
  • packcheck creates the source distribution and builds the package from the generated tarball to make sure that you build what you release and don’t miss adding a file to the distribution.
  • The most important part is that you can run exact same tests, in the same way, everywhere:

Out of the box support

Platforms Build Types CI Modes
Linux stack Travis
OSX cabal Appveyor
Windows cabal new-build CircleCI
Local Machine

The script can be easily adapted to any CI with a single line build command.

What is it?

The package packcheck includes a script called, it is a high level universal super build script to uniformly, consistently build and comprehensively sanity test a Haskell package across build tools (stack/cabal) and across all platforms (Linux/MacOS/Windows). You do not need to be familiar with any of the build tools to use it.

To make sure that it works everywhere without installing anything it is deliberately written in bash. Any of the parameters to control the builds can either be passed on the script command line or as environment variables for convenient use on CI systems.

packcheck is also a minimal yet complete “hello world” Haskell package with model travis and appveyor config files that can be used unmodified in any Haskell package. The CI configs can be modified declaratively, using environment variables, to adapt to any kind of build scenario you can imagine.

This model package has everything that a Haskell package usually has; including tests, benchmarks and Linux/MacOS/Windows CI already working. It can be used as a starting point to develop a new package. Beginners can use it to learn about haskell package metadata structure.

What all does it do?

An invocation of performs a whole battery of tests. packcheck is designed to be a simple to use tool for power users, you can control all aspects of the build process the way you want, see the reference section below.

Auto tool install and selection

  • Picks up the right version of GHC automatically (based on the version sepcified via an environment variable) if multiple versions are available in the PATH or from hvr-ghc style ghc/cabal installation.
  • When using stack builds, stack and ghc are installed automatically, if needed
  • For stack builds, if the package being tested does not have a stack.yaml it can even create it automatically using stack init.


  • build source
  • build benchmarks
  • build docs


  • run tests


  • run hlint

Coverage and Coveralls

  • generate coverage report
  • send coverage report to

Create and Test Source Distribution

  • create source distribution
  • build from source distribution
  • test installation after build
  • perform distribution checks

Usage Examples

You can run these commands on your local machine as well as inside a CI script. You can try these commands in the packcheck package itself:

$ ./ cabal-new GHCVER=8.4.1
$ ./ cabal GHCVER=7.10.3 CABALVER=1.22
$ cd packcheck
$ ./ stack RESOLVER=lts-11
$ ./ stack GHCVER=8.2.2
$ ./ stack RESOLVER=lts-7.24 STACK_YAML=stack-8.0.yaml STACK_BUILD_OPTIONS="--flag streamly:examples-sdl" CABALVER=1.24
# You can also do a cabal build using stack installed ghc:
$ stack exec ./ cabal RESOLVER=lts-11

Run hlint commands on the directories src and test:

$ ./ stack HLINT_COMMANDS="hlint lint src; hlint lint test"

Send coverage info of the testsuites named test1 and test2 to using hpc-coveralls.

$ ./ cabal GHCVER=8.0.2 COVERALLS_OPTIONS="test1 test2"

Full Reference

NOTE: Any of the parameters described below can either be passed on command line or as an environment variable. On a CI system you can just use a common command and control the build behavior for different builds using environment variables.

$ --help


For example:
./ stack RESOLVER=lts-10.0 GHC_OPTIONS="-O0 -Werror"

Control parameters can either be passed on command line or exported
as environment variables. Parameters marked DESTRUCTIVE may modify
your global user config or state.

stack                   : build using stack
cabal                   : build using cabal
cabal-new               : build using cabal new-build
clean                   : remove the .packcheck directory
cleanall                : remove .packcheck, .stack-work, .cabal-sandbox directories
help                    : show this help message

Selecting tool versions
GHCVER                  : [a.b.c] GHC version prefix (may not be enforced when using stack)
CABALVER                : [a.b.c.d] Cabal version (prefix) to use
RESOLVER                : Stack resolver to use for stack builds or cabal builds using stack
STACKVER                : [a.b.c.d] Stack version (prefix) to use
STACK_UPGRADE           : [y] DESTRUCTIVE! Upgrades stack to latest version

Where to find the required tools
PATH                    : [path] Set PATH explicitly for predictable builds
TOOLS_DIR               : [dir] Find ghc|cabal by version as in TOOLS_DIR/ghc/8.4.1/bin

Specifying common tool options
GHC_OPTIONS             : Specify GHC options to use
SDIST_OPTIONS           : Arguments to stack/cabal sdist command
CABAL_REINIT_CONFIG     : [y] DESTRUCTIVE! Remove old config to avoid incompatibility issues

Specifying what to build
DISABLE_BENCH           : [y] Do not build benchmarks, default is to build but not run
DISABLE_TEST            : [y] Do not run tests, default is to run tests
DISABLE_DOCS            : [y] Do not build haddocks, default is to build docs
DISABLE_SDIST_BUILD     : [y] Do not build from source distribution
DISABLE_DIST_CHECKS     : [y] Do not perform source distribution checks
ENABLE_INSTALL          : [y] DESTRUCTIVE! Install the package after building

stack options
STACK_YAML              : Alternative stack config, cannot be a path, just the file name
STACK_OPTIONS           : ADDITIONAL stack global options (e.g. -v) to append
STACK_BUILD_OPTIONS     : ADDITIONAL stack build command options to append

cabal options
CABAL_NEWBUILD_OPTIONS  : ADDITIONAL cabal new-build options to append
CABAL_NEWBUILD_TARGETS  : cabal new-build targets, default is 'all'
CABAL_CONFIGURE_OPTIONS : ADDITIONAL cabal old style configure options to append
CABAL_CHECK_RELAX       : [y] Do not fail if cabal check fails on the package.
CABAL_NO_SANDBOX        : [y] DESTRUCTIVE! Clobber (force install) global cabal ghc package db
CABAL_HACKAGE_MIRROR    : [y] DESTRUCTIVE! Specify an alternative mirror, modifies the cabal config file.

Coverage options
COVERALLS_OPTIONS       : hpc-coveralls args and options, usually just test suite names
COVERAGE                : [y] Just generate coverage information

hlint options
HLINT_COMMANDS          : hlint commands e.g.'hlint lint src; hlint lint test'

Diagnostics options
CHECK_ENV               : [y] Treat unknown env variables as error, used with env -i
BASE_TIME               : System time to be used as base for timeline reporting

Options marked DESTRUCTIVE! are fine in a CI environment. But on a local machine sometimes it may not be desirable as it will change the state of your global cabal config, so consider that before using these options.

By default cabal builds are done using sandboxes. It creates any temporary files or build artifacts inside .packcheck directory. See the clean and cleanall commands to release the temporary space.

stack is automatically installed and can be used to do cabal builds as well. If you specify BUILD=cabal-new and RESOLVER at the same time then the cabal build uses stack installed cabal and ghc, both are installed automatically when needed.

For pure cabal builds i.e. when BUILD=cabal-new and RESOLVER is not specified, cabal and ghc must be pre-installed on the system before building.


There may be issues due to some environment variables unknowingly set or some command line parameters or env variables being misspelled and therefore silently ignored. To avoid any such issues the robust way to invoke packcheck is to use a clean environment using env -i and passing CHECK_ENV=y parameter. When this parameter is set unwanted/misspelled variables are detected and reported.

$ env -i CHECK_ENV=y ./ stack

For performance diagnostics packcheck prints the time elapsed from the beginning at each build step performed.



  • Disable hpc-coveralls by default


  • Add support for circle CI
  • Add support for multi-package stack as well as cabal repos
  • Add a version command
  • Add CABAL_NEWBUILD_TARGETS envvar to build specific targets
  • Add GHC 8.6.1 in build matrices


  • Add a new environment var option DISABLE_DIST_CHECKS to disable source distribution checks. This can be used as a workaround for a bug in stack causing “stack sdist” to fail.
  • For stack builds, use the same options (STACK_BUILD_OPTIONS) for install test as for build so that an extra rebuild does not occur during install.
  • Workaround to avoid depending on cabal info command; in certain cases this command crashes cabal. See issue #13.



  • Add cabal new-build support. Use cabal-new to use it.
  • Add knobs to disable tests or doc builds (DISABLE_TEST, DISABLE_DOCS)
  • Now you can specify multiple versions of GHC in PATH and packcheck automatically finds the right one based on GHCVER envvar.
  • Add TOOLS_DIR option to specify hvr-ghc style installation of ghc and cabal. A correct version of GHC is automatically picked from this directory.
  • GHCVER and CABALVER variables are now optional in travis config if you specify the cabal and ghc PPAs under apt sources.
  • Run autoreconf if there is a in the package dir


  • TEST_INSTALL option is deprecated, use ENABLE_INSTALL instead


Breaking Changes

  • Make STACK_BUILD_OPTIONS and CABAL_CONFIGURE_OPTIONS append to the existing build/configure options instead of overriding them.
  • Do not enforce specific stack version in CI configs - this is done to avoid failures due to github API limits when upgrading or downgrading.

Bug Fixes

  • Avoid build failures in cases when cabal-install has to be installed and its dependencies may conflict with the current project dependencies.


  • Better documentation in travis and appveyor configs
  • Reduce the number of builds in default config from 11 to 6


  • Enhancement: Nix support; fix bash location to make it work on NixOS and potentially on other systems.


  • Initial release
Depends on 1 package:
comments powered byDisqus