See https://haskellstack.org for
installation and upgrade instructions.
Note: we are releasing a bit earlier than planned due to
As such, not all the binaries have been built yet, but the commonly
used 64-bit binaries of Linux static, macOS, and Windows are
In addition, the Windows installer and binary has not been
codesigned (we are awaiting validation of a new codesign
certificate), and you may see a “Windows Defender SmartScreen
prevented an unrecognized app from starting” warning when you try
to run them. If so, click on More info, and then
click on the Run anyway button that appears.
Major changes since v1.5.1
- Complete overhaul of how snapshots are defined, the
extra-deps fields, and a
number of related items. For full details, please see the writeup on
these changes. PR
#3249, see the PR description for a number of related
- Upgraded to version 2.0 of the Cabal library.
--install-ghc flag is now on by default. For
example, if you run
stack build in a directory
requiring a GHC that you do not currently have, Stack will
automatically download and install that GHC. You can explicitly set
install-ghc: false or pass the flag
--no-install-ghc to regain the previous behavior.
stack ghci no longer loads modules grouped by
package. This is always an improvement for plain ghci - it makes
loading faster and less noisy. For intero, this has the side-effect
that it will no longer load multiple packages that depend on TH
loading relative paths. TH relative paths will still work when
loading a single package into intero. See #3309
- Setting GHC options for a package via
stack.yaml will promote it to a local package,
providing for more consistency with flags and better
reproducibility. See: #849
package-indices setting with Hackage no longer
works with the
00-index.tar.gz tarball, but must use
01-index.tar.gz file to allow revised packages to
- Options passsed via
--ghci-options are now passed
to the end of the invocation of ghci, instead of the middle. This
+RTS without an accompanying
- When auto-detecting
tinfo6 is now preferred over
both versions of libtinfo are installed
- Addition of
stack build --copy-compiler-tool, to
allow tools like intero to be installed globally for a particular
- Stack will ask before saving hackage credentials to file. This
new prompt can be avoided by using the
save-hackage-creds setting. Please see #2159.
GHCRTS environment variable will no longer be
passed through to every program stack runs. Instead, it will only
be passed through commands like
ghc-options: for specific packages will now come
after the options specified for all packages / particular sets of
packages. See #3573.
pvp-bounds feature is no longer fully
functional, due to some issues with the Cabal library's printer.
with-hpack configuration option specifies an
Hpack executable to use instead of the Hpack bundled with Stack.
Please see #3179.
- It's now possible to skip tests and benchmarks using
GitSHA1 is now
StaticSHA256 and is
implemented using the
StaticSize 64 ByteString for
improved performance. See #3006
- Dependencies via HTTP(S) archives have been generalized to
allow local file path archives, as well as to support setting a
cryptographic hash (SHA256) of the contents for better
- Allow specifying
--git-branch when upgrading
- When running
stack upgrade from a file which is
different from the default executable path (e.g., on POSIX systems,
~/.local/bin/stack), it will now additionally copy the
new executable over the currently running
executable. If permission is denied (such as in
/usr/local/bin/stack), the user will be prompted to
try again using
sudo. This is intended to assist with
the user experience when the
PATH environment variable
has not been properly configured, see #3232.
stack setup for ghcjs will now install
happy if they are not present.
stack ghci --only-main flag, to skip loading
/ importing all but main modules. See the ghci documentation page
for further info.
- Allow GHC's colored output to show through. GHC colors output
starting with version 8.2.1, for older GHC this does nothing.
Sometimes GHC's heuristics would work fine even before this change,
for example in
stack ghci, but this override's GHC's
heuristics when they're broken by our collecting and processing
- Extended the
ghc-options field to support
$everything. See: #3329
- Better error message for case that
stack ghci file
targets are combined with invalid package targets. See: #3342
- For profiling now uses
instead of the deprecated
-auto-all -caf-all. See:
- Better descriptions are now available for
--help. See: #3070
- When using Nix, nix-shell now depends always on gcc to prevent
build errors when using the FFI. As ghc depends on gcc anyway, this
doesn't increase the dependency footprint.
--cwd DIR can now be passed to
exec in order to execute the program in a different
directory. See: #3264
- Plan construction will detect if you add an executable-only
package as a library dependency, resulting in much clearer error
messages. See: #2195.
- Addition of
script to pass options directly to GHC. See: #3454
- Add hpack
package.yaml to build Stack itself
ignore-revision-mismatch setting. See:
- Log when each individual test suite finishes. See: #3552.
- Avoid spurious rebuilds when using
not watching files for executable, test and benchmark components
that aren't a target. See: #3483.
- Stack will now try to detect the width of the running terminal
(only on POSIX for the moment) and use that to better display
output messages. Work is ongoing, so some messages will not be
optimal yet. The terminal width can be overriden with the new
--terminal-width command-line option (this works even
- Passing non local packages as targets to
ghci will now cause them to be used as
args along with package hiding.
- Detect when user changed .cabal file instead of package.yaml.
This was implemented upstream in hpack. See #3383.
- Automatically run
autoreconf -i as necessary when
configure script is missing. See #3534
- GHC bindists can now be identified by their SHA256 checksum in
addition to their SHA1 checksum, allowing for more security in
- For filesystem setup-info paths, it's no longer assumed that
the directory is writable, instead a temp dir is used. See #3188.
stack hoogle correctly generates Hoogle databases.
stack --docker-help is now clearer about –docker
implying system-ghc: true, rather than both –docker and
stack haddock now includes package names for all
modules in the Haddock index page. See: #2886
- Fixed an issue where Stack wouldn't detect missing Docker
images properly with newer Docker versions. #3171
- Previously, cabal files with just test-suite could cause build
to fail (#2862)
- If an invalid snapshot file has been detected (usually due to
mismatched hashes), Stack will delete the downloaded file and
recommend either retrying or filing an issue upstream. See #3319.
- Modified the flag parser within Stack to match the behavior of
Cabal's flag parser, which allows multiple sequential dashes. See
- Now clears the hackage index cache if it is older than the
downloaded index. Fixes potential issue if stack was interrupted
when updating index. See #3033
- The Stack install script now respects the
option. See #3366.
stack script can now handle relative paths to
source files. See #3372.
- Fixes explanation of why a target is needed by the build plan,
when the target is an extra dependency from the commandline. See
- Previously, if you delete a yaml file from ~/.stack/build-plan,
it would trust the etag and not re-download. Fixed in this
stack --docker in parallel now correctly
locks the sqlite database. See #3400.
- docs.haskellstack.org RTD documentation search is replaced by
the mkdocs search. Please see #3376.
stack clean now works with nix. See #3468.
stack build --only-dependencies no longer builds
local project packages that are depended on. See #3476.
- Properly handle relative paths stored in the precompiled cache
files. See #3431.
- In some cases, Cabal does not realize that it needs to
reconfigure, and must be told to do so automatically. This would
manifest as a “shadowed dependency” error message. We now force a
reconfigure whenever a dependency is built, even if the package ID
remained the same. See #2781.
--pvp-bounds is enabled for sdist or upload,
internal dependencies could cause errors when uploaded to hackage.
This is fixed, see #3290
- Fixes a bug where nonexistent hackage versions would cause
stack to suggest the same package name, without giving version
info. See #3562
- Fixes a bug that has existed since 1.5.0, where
setup --upgrade-cabal would say that Cabal is already the
latest version, when it wasn't.
- Ensure that an
extra-dep from a local directory is
not treated as a
$locals for GHC options purposes. See
- Building all executables only happens once instead of every
time. See #3229
for more info.
Thanks to all our contributors for this release:
- Aaron McDaid
- Adam McCullough
- Alexey Zabelin
- Ashley Towns
- Chris Done
- Chris Martin
- Deni Bertovic
- Dmitry Ivanov
- Echo Nolan
- Emanuel Borsboom
- Felix Yan
- Filippo Vitale
- Gábor Lipták
- Ivan Lazar Miljenovic
- Joshua Simmons
- Judah Jacobson
- Khan Thompson
- Lizao Li
- Luke Murphy
- Martin Kolinek
- Mathieu Boespflug
- Matt Audesse
- Matthias Heinzel
- Michael Sloan
- Michael Snoyman
- Neil Mitchell
- Oleg Grenrus
- Paolo G. Giarrusso
- Reuben D'Netto
- Roman Cheplyaka
- Samuli Thomasson
- Scott Fleischman
- Shea Levy
- Simon Jakobi
- Tom Sydney Kerckhove
- Walter Franzini
Do you like this blog post and need help with DevOps, Rust or functional programming? Contact us.