# GHC 9.0.1 released

**URL:** <https://discourse.haskell.org/t/ghc-9-0-1-released/1840>\
**Category:** Announcements\
**Created:** [February 4, 2021, 5:58pm UTC](https://discourse.haskell.org/t/ghc-9-0-1-released/1840 "2021-02-04T17:58:58Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![bgamari](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.haskell.org/bgamari/32/3599_2.png) [@bgamari](https://discourse.haskell.org/u/bgamari)\
**Post date:** [February 4, 2021, 5:58pm UTC](https://discourse.haskell.org/t/ghc-9-0-1-released/1840/1 "2021-02-04T17:58:58Z")

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The GHC team is very pleased to announce the availability of GHC 9.0.1.  
Source and binary distributions are available at the [usual  
place](https://downloads.haskell.org/ghc/9.0.1/).

In addition to numerous bug fixes, GHC 9.0.1 will bring a number of new  
features:

- A first cut of the new `LinearTypes` [language extension](https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0111-linear-types.rst), allowing use  
of linear function syntax and linear record fields.

- A new bignum library, `ghc-bignum`, improving portability and allowing GHC  
to be more easily used with integer libraries other than GMP.

- Improvements in code generation, resulting in considerable  
runtime performance improvements in some programs.

- Improvements in pattern-match checking, allowing more precise  
detection of redundant cases and reduced compilation time.

- Implementation of the “simplified subsumption” [proposal](https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0287-simplify-subsumption.rst)  
simplifying the type system and paving the way for QuickLook  
impredicativity in GHC 9.2.

- Implementation of the `QualifiedDo` [extension](https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0216-qualified-do.rst), allowing more  
convenient overloading of `do` syntax.

- An experimental new IO manager implementation for Windows platforms, both  
improving performance and fixing many of the quirks with the old manager built  
on POSIX-emulation.

- Improvements in compilation time.

And many more. See the [release notes](https://downloads.haskell.org/ghc/9.0.1/docs/html/users_guide/9.0.1-notes.html) for a full accounting of the  
changes in this release.

As always, feel free to report any issues you encounter via  
[gitlab.haskell.org](https://gitlab.haskell.org/ghc/ghc/-/issues/new).