diff --git a/.github/workflows/nix.yml b/.github/workflows/nix.yml
index eff8fa2123..8458eea89c 100644
--- a/.github/workflows/nix.yml
+++ b/.github/workflows/nix.yml
@@ -113,8 +113,10 @@ jobs:
       run: cachix push haskell-language-server dev
     - name: Build binaries
       run: nix build --print-build-logs
-    - name: Build all binaries
-      run: nix build --print-build-logs .#all-haskell-language-server
+    # smunix: "Build all binaries" takes too long to run and doesn't contribute
+    # to caching to cachix for now; so I'm disabling it for now.
+    # - name: Build all binaries
+    #   run: nix build --print-build-logs .#all-haskell-language-server
     - name: Push binaries
       if: ${{ env.HAS_TOKEN == 'true' }}
       run: nix path-info --json | jq -r '.[].path' | cachix push haskell-language-server
diff --git a/.gitignore b/.gitignore
index 8b90d20187..61cfe5877b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -31,7 +31,7 @@ test/testdata/**/hie.yaml
 .shake/
 
 # pre-commit-hook.nix
-#.pre-commit-config.yaml
+.pre-commit-config.yaml
 
 # direnv
 /.direnv/
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 4d4ad3ccc5..39025fb2b7 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -16,7 +16,7 @@ variables:
     - GHC_VERSION: 8.10.7
       CABAL_PROJECT: cabal.project
     - GHC_VERSION: 9.0.2
-      CABAL_PROJECT: cabal-ghc90.project
+      CABAL_PROJECT: cabal.project
     - GHC_VERSION: 9.2.2
       CABAL_PROJECT: cabal-ghc92.project
     - GHC_VERSION: 9.2.1
diff --git a/bindist/ghcs b/bindist/ghcs
index 32cfc187ed..154935c5ae 100644
--- a/bindist/ghcs
+++ b/bindist/ghcs
@@ -1,6 +1,6 @@
 8.6.5,cabal.project
 8.8.4,cabal.project
 8.10.7,cabal.project
-9.0.2,cabal-ghc90.project
+9.0.2,cabal.project
 9.2.1,cabal-ghc92.project
 9.2.2,cabal-ghc92.project
diff --git a/bindist/ghcs-FreeBSD b/bindist/ghcs-FreeBSD
index cab2c69bb2..a1b4b6e0bf 100644
--- a/bindist/ghcs-FreeBSD
+++ b/bindist/ghcs-FreeBSD
@@ -1,2 +1,2 @@
 8.10.7,cabal.project
-9.0.2,cabal-ghc90.project
+9.0.2,cabal.project
diff --git a/bindist/ghcs-Msys b/bindist/ghcs-Msys
index a6210abe73..37998b56f1 100644
--- a/bindist/ghcs-Msys
+++ b/bindist/ghcs-Msys
@@ -1,4 +1,4 @@
 8.10.7,cabal.project
-9.0.2,cabal-ghc90.project
+9.0.2,cabal.project
 9.2.2,cabal-ghc92.project
 9.2.1,cabal-ghc92.project
diff --git a/cabal-ghc90.project b/cabal-ghc90.project
deleted file mode 100644
index 06e0d35262..0000000000
--- a/cabal-ghc90.project
+++ /dev/null
@@ -1,58 +0,0 @@
-packages:
-         ./
-         ./hie-compat
-         ./shake-bench
-         ./hls-graph
-         ./ghcide
-         ./hls-plugin-api
-         ./hls-test-utils
-         ./plugins/hls-tactics-plugin
-         ./plugins/hls-brittany-plugin
-         ./plugins/hls-stylish-haskell-plugin
-         ./plugins/hls-fourmolu-plugin
-         ./plugins/hls-class-plugin
-         ./plugins/hls-eval-plugin
-         ./plugins/hls-explicit-imports-plugin
-         ./plugins/hls-refine-imports-plugin
-         ./plugins/hls-hlint-plugin
-         ./plugins/hls-rename-plugin
-         ./plugins/hls-retrie-plugin
-         ./plugins/hls-haddock-comments-plugin
-         ./plugins/hls-splice-plugin
-         ./plugins/hls-qualify-imported-names-plugin
-         ./plugins/hls-floskell-plugin
-         ./plugins/hls-pragmas-plugin
-         ./plugins/hls-module-name-plugin
-         ./plugins/hls-ormolu-plugin
-         ./plugins/hls-call-hierarchy-plugin
-         ./plugins/hls-alternate-number-format-plugin
-         ./plugins/hls-selection-range-plugin
-         ./plugins/hls-change-type-signature-plugin
-
-tests: true
-
-package *
-  ghc-options: -haddock
-  test-show-details: direct
-
-write-ghc-environment-files: never
-
-index-state: 2022-04-27T09:22:49Z
-
-constraints:
-
--- although we are not building all plugins cabal solver phase is run for all packages
--- this way we track explicitly all transitive dependencies which need support for ghc-9
-allow-newer:
-
-  -- brittany: update ghc bounds in hls.cabal when those are removed
-  -- https://github.com/lspitzner/multistate/pull/8
-  multistate:base,
-  -- https://github.com/lspitzner/data-tree-print/pull/3
-  data-tree-print:base,
-  -- https://github.com/lspitzner/butcher/pull/8
-  butcher:base,
-
-  -- ghc-9.0.2 specific
-  -- for ghcide:test via ghc-typelits-knownnat
-  ghc-typelits-natnormalise:ghc-bignum
diff --git a/cabal-ghc92.project b/cabal-ghc92.project
index 136ea7365b..f0d47d04cb 100644
--- a/cabal-ghc92.project
+++ b/cabal-ghc92.project
@@ -39,7 +39,7 @@ package *
 
 write-ghc-environment-files: never
 
-index-state: 2022-04-27T09:22:49Z
+index-state: 2022-04-30T21:02:45Z
 
 constraints:
   -- These plugins don't build/work on GHC92 yet
diff --git a/cabal.project b/cabal.project
index ea1114f19a..3afb72dfac 100644
--- a/cabal.project
+++ b/cabal.project
@@ -37,21 +37,15 @@ optional-packages: vendored/*/*.cabal
 tests: true
 
 package *
-  -- ghc 8.10 cannot build ghc-lib 9.2 with --haddock
-  -- ghc-options: -haddock
+  -- ghc 8.10.7 fails to build ghc-lib-9.2.2
+  -- ghc-options: --haddock
   test-show-details: direct
 
 write-ghc-environment-files: never
 
-index-state: 2022-04-27T09:22:49Z
+index-state: 2022-04-30T21:02:45Z
 
 constraints:
-    hyphenation +embed,
-    -- remove this when hlint sets ghc-lib to true by default
-    -- https://github.com/ndmitchell/hlint/issues/1376
-    hlint +ghc-lib
+  hyphenation +embed,
+  hls-hlint-plugin +ghc-lib,
 
-allow-newer:
-    -- for shake-bench
-    Chart-diagrams:diagrams-core,
-    SVGFonts:diagrams-core
diff --git a/configuration-ghc-810.nix b/configuration-ghc-810.nix
new file mode 100644
index 0000000000..49be331855
--- /dev/null
+++ b/configuration-ghc-810.nix
@@ -0,0 +1,58 @@
+{ pkgs, inputs }:
+
+let
+  disabledPlugins = [
+    "hls-brittany-plugin"
+    "hls-hlint-plugin"
+    "hls-stylish-haskell-plugin"
+    "hls-haddock-comments-plugin"
+    "hls-tactics-plugin"
+    # That one is not technically a plugin, but by putting it in this list, we
+    # get it removed from the top level list of requirement and it is not pull
+    # in the nix shell.
+    "shake-bench"
+  ];
+
+  hpkgsOverride = hself: hsuper:
+    with pkgs.haskell.lib; {
+      hlsDisabledPlugins = disabledPlugins;
+
+      ghc-lib = hself.ghc-lib_8_10_7_20220219;
+      ghc-lib-parser = hself.ghc-lib-parser_8_10_7_20220219;
+
+      fourmolu = hself.callCabal2nix "fourmolu" inputs.fourmolu-0300 { };
+
+      stylish-haskell = hself.callCabal2nixWithOptions "stylish-haskell"
+        inputs.stylish-haskell-01220 (pkgs.lib.concatStringsSep " " [ ]) { };
+
+      aeson = hself.callCabal2nixWithOptions "aeson" inputs.aeson-1520
+        (pkgs.lib.concatStringsSep " " [ ]) { };
+
+      brittany = hself.callCabal2nixWithOptions "brittany" inputs.brittany-01312
+        (pkgs.lib.concatStringsSep " " [ ]) { };
+
+      hls-hlint-plugin = hself.callCabal2nixWithOptions "hls-hlint-plugin"
+        ./plugins/hls-hlint-plugin
+        (pkgs.lib.concatStringsSep " " [ "-f-hlint34" "-fhyphenation" ]) { };
+
+      # Re-generate HLS drv excluding some plugins
+      haskell-language-server =
+        hself.callCabal2nixWithOptions "haskell-language-server" ./.
+        (pkgs.lib.concatStringsSep " " [
+          "-fpedantic"
+          "-f-hlint"
+          "-f-fourmolu"
+          "-f-ormolu"
+        ]) { };
+
+      # YOLO
+      mkDerivation = args:
+        hsuper.mkDerivation (args // {
+          jailbreak = true;
+          doCheck = false;
+        });
+    };
+in {
+  inherit disabledPlugins;
+  tweakHpkgs = hpkgs: hpkgs.extend hpkgsOverride;
+}
diff --git a/configuration-ghc-88.nix b/configuration-ghc-88.nix
new file mode 100644
index 0000000000..49be331855
--- /dev/null
+++ b/configuration-ghc-88.nix
@@ -0,0 +1,58 @@
+{ pkgs, inputs }:
+
+let
+  disabledPlugins = [
+    "hls-brittany-plugin"
+    "hls-hlint-plugin"
+    "hls-stylish-haskell-plugin"
+    "hls-haddock-comments-plugin"
+    "hls-tactics-plugin"
+    # That one is not technically a plugin, but by putting it in this list, we
+    # get it removed from the top level list of requirement and it is not pull
+    # in the nix shell.
+    "shake-bench"
+  ];
+
+  hpkgsOverride = hself: hsuper:
+    with pkgs.haskell.lib; {
+      hlsDisabledPlugins = disabledPlugins;
+
+      ghc-lib = hself.ghc-lib_8_10_7_20220219;
+      ghc-lib-parser = hself.ghc-lib-parser_8_10_7_20220219;
+
+      fourmolu = hself.callCabal2nix "fourmolu" inputs.fourmolu-0300 { };
+
+      stylish-haskell = hself.callCabal2nixWithOptions "stylish-haskell"
+        inputs.stylish-haskell-01220 (pkgs.lib.concatStringsSep " " [ ]) { };
+
+      aeson = hself.callCabal2nixWithOptions "aeson" inputs.aeson-1520
+        (pkgs.lib.concatStringsSep " " [ ]) { };
+
+      brittany = hself.callCabal2nixWithOptions "brittany" inputs.brittany-01312
+        (pkgs.lib.concatStringsSep " " [ ]) { };
+
+      hls-hlint-plugin = hself.callCabal2nixWithOptions "hls-hlint-plugin"
+        ./plugins/hls-hlint-plugin
+        (pkgs.lib.concatStringsSep " " [ "-f-hlint34" "-fhyphenation" ]) { };
+
+      # Re-generate HLS drv excluding some plugins
+      haskell-language-server =
+        hself.callCabal2nixWithOptions "haskell-language-server" ./.
+        (pkgs.lib.concatStringsSep " " [
+          "-fpedantic"
+          "-f-hlint"
+          "-f-fourmolu"
+          "-f-ormolu"
+        ]) { };
+
+      # YOLO
+      mkDerivation = args:
+        hsuper.mkDerivation (args // {
+          jailbreak = true;
+          doCheck = false;
+        });
+    };
+in {
+  inherit disabledPlugins;
+  tweakHpkgs = hpkgs: hpkgs.extend hpkgsOverride;
+}
diff --git a/configuration-ghc-90.nix b/configuration-ghc-90.nix
new file mode 100644
index 0000000000..bbf7eafbb1
--- /dev/null
+++ b/configuration-ghc-90.nix
@@ -0,0 +1,45 @@
+{ pkgs, inputs }:
+
+let
+  disabledPlugins = [ "hls-brittany-plugin" "hls-stylish-haskell-plugin" ];
+
+  hpkgsOverride = hself: hsuper:
+    with pkgs.haskell.lib; {
+      hlsDisabledPlugins = disabledPlugins;
+
+      # ptr-poker breaks on MacOS without SSE2 optimizations
+      # https://github.com/nikita-volkov/ptr-poker/issues/11
+      ptr-poker = hself.callCabal2nix "ptr-poker" inputs.ptr-poker { };
+
+      ghc-lib = hself.ghc-lib_9_2_2_20220307;
+      ghc-lib-parser = hself.ghc-lib-parser_9_2_2_20220307;
+      ghc-lib-parser-ex = hself.ghc-lib-parser-ex_9_2_0_3;
+
+      Cabal = hself.Cabal_3_6_3_0;
+      ormolu = hself.ormolu_0_4_0_0;
+      fourmolu = hself.fourmolu_0_6_0_0;
+
+      # Hlint is still broken
+      hlint = doJailbreak (hself.callCabal2nix "hlint" inputs.hlint-34 { });
+
+      hls-hlint-plugin = hself.callCabal2nixWithOptions "hls-hlint-plugin"
+        ./plugins/hls-hlint-plugin
+        (pkgs.lib.concatStringsSep " " [ "-fhlint34" "-fghc-lib" ]) { };
+
+      # Re-generate HLS drv excluding some plugins
+      haskell-language-server =
+        hself.callCabal2nixWithOptions "haskell-language-server" ./.
+        (pkgs.lib.concatStringsSep " " [ "-f-brittany" "-f-stylishhaskell" ])
+        { };
+
+      # YOLO
+      mkDerivation = args:
+        hsuper.mkDerivation (args // {
+          jailbreak = true;
+          doCheck = false;
+        });
+    };
+in {
+  inherit disabledPlugins;
+  tweakHpkgs = hpkgs: hpkgs.extend hpkgsOverride;
+}
diff --git a/configuration-ghc-901.nix b/configuration-ghc-901.nix
deleted file mode 100644
index 789a5d2e19..0000000000
--- a/configuration-ghc-901.nix
+++ /dev/null
@@ -1,36 +0,0 @@
-# nix version of cabal-ghc901.project
-{ pkgs }:
-
-let
-  disabledPlugins = [
-    "hls-brittany-plugin"
-    "hls-stylish-haskell-plugin"
-  ];
-
-  hpkgsOverride = hself: hsuper:
-    with pkgs.haskell.lib;
-    {
-      hlsDisabledPlugins = disabledPlugins;
-
-      fourmolu = hself.fourmolu_0_4_0_0;
-      primitive-extras = hself.primitive-extras_0_10_1_2;
-
-      # Re-generate HLS drv excluding some plugins
-      haskell-language-server =
-        hself.callCabal2nixWithOptions "haskell-language-server" ./.
-        (pkgs.lib.concatStringsSep " " [
-          "-f-brittany"
-          "-f-stylishhaskell"
-        ]) { };
-
-      # YOLO
-      mkDerivation = args:
-        hsuper.mkDerivation (args // {
-          jailbreak = true;
-          doCheck = false;
-        });
-    };
-in {
-  inherit disabledPlugins;
-  tweakHpkgs = hpkgs: hpkgs.extend hpkgsOverride;
-}
diff --git a/configuration-ghc-921.nix b/configuration-ghc-92.nix
similarity index 69%
rename from configuration-ghc-921.nix
rename to configuration-ghc-92.nix
index d8660da1d9..b44e0fba67 100644
--- a/configuration-ghc-921.nix
+++ b/configuration-ghc-92.nix
@@ -1,4 +1,3 @@
-# nix version of cabal-ghc901.project
 { pkgs, inputs }:
 
 let
@@ -14,19 +13,22 @@ let
   ];
 
   hpkgsOverride = hself: hsuper:
-    with pkgs.haskell.lib;
-    {
+    with pkgs.haskell.lib; {
       hlsDisabledPlugins = disabledPlugins;
 
-      fourmolu = hself.callCabal2nix "fourmolu" inputs.fourmolu {};
-      primitive-extras = hself.primitive-extras_0_10_1_2;
-      ghc-exactprint = hself.callCabal2nix "ghc-exactprint" inputs.ghc-exactprint {};
-      constraints-extras = hself.callCabal2nix "constraints-extras" inputs.constraints-extras {};
-      retrie = hself.callCabal2nix "retrie" inputs.retrie {};
+      fourmolu = hself.callCabal2nix "fourmolu" inputs.fourmolu { };
+      ghc-exactprint =
+        hself.callCabal2nix "ghc-exactprint" inputs.ghc-exactprint-150 { };
+      constraints-extras =
+        hself.callCabal2nix "constraints-extras" inputs.constraints-extras { };
+      retrie = hself.callCabal2nix "retrie" inputs.retrie { };
+
+      # ptr-poker breaks on MacOS without SSE2 optimizations
+      # https://github.com/nikita-volkov/ptr-poker/issues/11
+      ptr-poker = hself.callCabal2nix "ptr-poker" inputs.ptr-poker { };
 
       # Hlint is still broken
-      hlint = doJailbreak (hself.callCabal2nix "hlint" inputs.hlint {});
-      hiedb = hself.hiedb_0_4_1_0;
+      hlint = doJailbreak (hself.callCabal2nix "hlint" inputs.hlint { });
 
       # Re-generate HLS drv excluding some plugins
       haskell-language-server =
diff --git a/docs/requirements.txt b/docs/requirements.txt
index 66d33da6c1..b46859cb93 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,4 +1,4 @@
 Sphinx==4.0.2
 sphinx-rtd-theme==0.5.2
 myst-parser==0.15.1
-docutils<0.17
+docutils<0.19
diff --git a/docs/troubleshooting.md b/docs/troubleshooting.md
index 68642dada1..192ea006f8 100644
--- a/docs/troubleshooting.md
+++ b/docs/troubleshooting.md
@@ -174,7 +174,7 @@ cabal update && cabal install :pkg:haskell-language-server
 If you are compiling with a ghc version with a specific `cabal-ghc${ghcVersion}.project` in the repo you will have to use it. For example for ghc-9.0.x:
 
 ```bash
-cabal update && cabal install :pkg:haskell-language-server --project-file=cabal-ghc90.project
+cabal update && cabal install pkg:haskell-language-server
 ```
 
 Or with `stack`:
@@ -192,7 +192,7 @@ ghcup compile hls -v 1.6.1.0 --ghc 8.10.7
 as it uses cabal underneath you might need to use a specific cabal.project for some ghc versions:
 
 ```bash
-ghcup compile hls -v 1.6.1.0 --ghc 9.0.2 --cabal-project cabal-ghc90.project
+ghcup compile hls -v 1.6.1.0 --ghc 9.0.2
 ```
 
 ### Preprocessors
diff --git a/docutils.nix b/docutils.nix
new file mode 100644
index 0000000000..1c47e1455d
--- /dev/null
+++ b/docutils.nix
@@ -0,0 +1,32 @@
+{ stdenv, lib, fetchPypi, buildPythonPackage, isPy3k, python }:
+
+buildPythonPackage rec {
+  pname = "docutils";
+  version = "0.17.1";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "686577d2e4c32380bb50cbb22f575ed742d58168cee37e99117a854bcd88f125";
+  };
+
+  # Only Darwin needs LANG, but we could set it in general.
+  # It's done here conditionally to prevent mass-rebuilds.
+  checkPhase = lib.optionalString (isPy3k && stdenv.isDarwin)
+    ''LANG="en_US.UTF-8" LC_ALL="en_US.UTF-8" '' + ''
+      ${python.interpreter} test/alltests.py
+    '';
+
+  # Create symlinks lacking a ".py" suffix, many programs depend on these names
+  postFixup = ''
+    for f in $out/bin/*.py; do
+      ln -s $(basename $f) $out/bin/$(basename $f .py)
+    done
+  '';
+
+  meta = with lib; {
+    description = "Python Documentation Utilities";
+    homepage = "http://docutils.sourceforge.net/";
+    license = with licenses; [ publicDomain bsd2 psfl gpl3Plus ];
+    maintainers = with maintainers; [ AndersonTorres ];
+  };
+}
diff --git a/flake.lock b/flake.lock
index b1d15496c1..c73bd0fc2b 100644
--- a/flake.lock
+++ b/flake.lock
@@ -1,5 +1,29 @@
 {
   "nodes": {
+    "aeson-1520": {
+      "flake": false,
+      "locked": {
+        "narHash": "sha256-btKp7CTOgC0wT33lROffARW9qr1jx9oKE5EWydaR52c=",
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/aeson-1.5.2.0/aeson-1.5.2.0.tar.gz"
+      },
+      "original": {
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/aeson-1.5.2.0/aeson-1.5.2.0.tar.gz"
+      }
+    },
+    "brittany-01312": {
+      "flake": false,
+      "locked": {
+        "narHash": "sha256-4rDE2bu4C8cv1D6lkTtLxMwLRyDfIK70BnptSrygK60=",
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/brittany-0.13.1.2/brittany-0.13.1.2.tar.gz"
+      },
+      "original": {
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/brittany-0.13.1.2/brittany-0.13.1.2.tar.gz"
+      }
+    },
     "constraints-extras": {
       "flake": false,
       "locked": {
@@ -15,11 +39,11 @@
     "flake-compat": {
       "flake": false,
       "locked": {
-        "lastModified": 1641205782,
-        "narHash": "sha256-4jY7RCWUoZ9cKD8co0/4tFARpWB+57+r1bLLvXNJliY=",
+        "lastModified": 1650374568,
+        "narHash": "sha256-Z+s0J8/r907g149rllvwhb4pKi8Wam5ij0st8PwAh+E=",
         "owner": "edolstra",
         "repo": "flake-compat",
-        "rev": "b7547d3eed6f32d06102ead8991ec52ab0a4f1a7",
+        "rev": "b4a34015c698c7793d592d66adbab377907a2be8",
         "type": "github"
       },
       "original": {
@@ -30,11 +54,11 @@
     },
     "flake-utils": {
       "locked": {
-        "lastModified": 1629481132,
-        "narHash": "sha256-JHgasjPR0/J1J3DRm4KxM4zTyAj4IOJY8vIl75v/kPI=",
+        "lastModified": 1649676176,
+        "narHash": "sha256-OWKJratjt2RW151VUlJPRALb7OU2S5s+f0vLj4o1bHM=",
         "owner": "numtide",
         "repo": "flake-utils",
-        "rev": "997f7efcb746a9c140ce1f13c72263189225f482",
+        "rev": "a4b154ebbdc88c8498a5c7b01589addc9e9cb678",
         "type": "github"
       },
       "original": {
@@ -45,11 +69,26 @@
     },
     "flake-utils_2": {
       "locked": {
-        "lastModified": 1638122382,
-        "narHash": "sha256-sQzZzAbvKEqN9s0bzWuYmRaA03v40gaJ4+iL1LXjaeI=",
+        "lastModified": 1649676176,
+        "narHash": "sha256-OWKJratjt2RW151VUlJPRALb7OU2S5s+f0vLj4o1bHM=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "a4b154ebbdc88c8498a5c7b01589addc9e9cb678",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "flake-utils_3": {
+      "locked": {
+        "lastModified": 1644229661,
+        "narHash": "sha256-1YdnJAsNy69bpcjuoKdOYQX0YxZBiCYZo4Twxerqv7k=",
         "owner": "numtide",
         "repo": "flake-utils",
-        "rev": "74f7e4319258e287b0f9cb95426c9853b282730b",
+        "rev": "3cecb5b042f7f209c56ffd8371b2711a290ec797",
         "type": "github"
       },
       "original": {
@@ -70,6 +109,18 @@
         "url": "https://hackage.haskell.org/package/fourmolu-0.5.0.1/fourmolu-0.5.0.1.tar.gz"
       }
     },
+    "fourmolu-0300": {
+      "flake": false,
+      "locked": {
+        "narHash": "sha256-SFBwhkXfDArITiBSxGSp2qf8gl+yBpWHglBB5aKeaBU=",
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/fourmolu-0.3.0.0/fourmolu-0.3.0.0.tar.gz"
+      },
+      "original": {
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/fourmolu-0.3.0.0/fourmolu-0.3.0.0.tar.gz"
+      }
+    },
     "ghc-exactprint": {
       "flake": false,
       "locked": {
@@ -82,14 +133,26 @@
         "url": "https://hackage.haskell.org/package/ghc-exactprint-1.4.1/ghc-exactprint-1.4.1.tar.gz"
       }
     },
+    "ghc-exactprint-150": {
+      "flake": false,
+      "locked": {
+        "narHash": "sha256-f+WmS86c7B0dx2SMABIMm66z6sbRVWdqSZ1QBBEpUMw=",
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/ghc-exactprint-1.5.0/ghc-exactprint-1.5.0.tar.gz"
+      },
+      "original": {
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/ghc-exactprint-1.5.0/ghc-exactprint-1.5.0.tar.gz"
+      }
+    },
     "gitignore": {
       "flake": false,
       "locked": {
-        "lastModified": 1611672876,
-        "narHash": "sha256-qHu3uZ/o9jBHiA3MEKHJ06k7w4heOhA+4HCSIvflRxo=",
+        "lastModified": 1646480205,
+        "narHash": "sha256-kekOlTlu45vuK2L9nq8iVN17V3sB0WWPqTTW3a2SQG0=",
         "owner": "hercules-ci",
         "repo": "gitignore.nix",
-        "rev": "211907489e9f198594c0eb0ca9256a1949c9d412",
+        "rev": "bff2832ec341cf30acb3a4d3e2e7f1f7b590116a",
         "type": "github"
       },
       "original": {
@@ -101,13 +164,13 @@
     "hie-bios": {
       "flake": false,
       "locked": {
-        "narHash": "sha256-nd+FfUQVZNxJfKZkAWA3dF0JwRgXntL+1gGvyNHDbKc=",
+        "narHash": "sha256-5RqspT27rb/tMBwrKr4VfSSbq0+c0LMNuaKlTun0Kkk=",
         "type": "tarball",
-        "url": "https://hackage.haskell.org/package/hie-bios-0.9.0/hie-bios-0.9.0.tar.gz"
+        "url": "https://hackage.haskell.org/package/hie-bios-0.9.1/hie-bios-0.9.1.tar.gz"
       },
       "original": {
         "type": "tarball",
-        "url": "https://hackage.haskell.org/package/hie-bios-0.9.0/hie-bios-0.9.0.tar.gz"
+        "url": "https://hackage.haskell.org/package/hie-bios-0.9.1/hie-bios-0.9.1.tar.gz"
       }
     },
     "hlint": {
@@ -122,6 +185,18 @@
         "url": "https://hackage.haskell.org/package/hlint-3.3.6/hlint-3.3.6.tar.gz"
       }
     },
+    "hlint-34": {
+      "flake": false,
+      "locked": {
+        "narHash": "sha256-mDncRtVkjWnUbZc1fgDMGcGjy8CFNxUF8z2HGuuN7GU=",
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/hlint-3.4/hlint-3.4.tar.gz"
+      },
+      "original": {
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/hlint-3.4/hlint-3.4.tar.gz"
+      }
+    },
     "implicit-hie-cradle": {
       "flake": false,
       "locked": {
@@ -170,13 +245,30 @@
         "url": "https://hackage.haskell.org/package/lsp-types-1.4.0.1/lsp-types-1.4.0.1.tar.gz"
       }
     },
+    "myst-parser": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1650933355,
+        "narHash": "sha256-Osd3urvH1bn9w/6sAMyLKHO7gxuYePpGJ9y8ReBfp4E=",
+        "owner": "smunix",
+        "repo": "MyST-Parser",
+        "rev": "57d0d78169a0e157406c35df951bdffdf94b4f9b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "smunix",
+        "ref": "fix.hls-docutils",
+        "repo": "MyST-Parser",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1639357775,
-        "narHash": "sha256-mJJFCPqZi1ZO3CvgEfN2nFAYv4uAJSRnTKzLFi61+WA=",
+        "lastModified": 1650792148,
+        "narHash": "sha256-n1MZSZIzvP70BJ56tV8GwQ5L0wHt/nTH9UkF5HTGB/4=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "c473cc8714710179df205b153f4e9fa007107ff9",
+        "rev": "ab83c5d70528f1edc7080dead3a5dee61797b3ff",
         "type": "github"
       },
       "original": {
@@ -188,11 +280,26 @@
     },
     "nixpkgs_2": {
       "locked": {
-        "lastModified": 1641016545,
-        "narHash": "sha256-JMNwvnBzG0RjGG3eH27Y5/GlJ9ryeCdGJfqGbqxnmZY=",
+        "lastModified": 1650933476,
+        "narHash": "sha256-kBefFyATME/AGGFMudAltOeKYnSc3YDOI0YgDjjIhzw=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "6f05cfdb1e78d36c0337516df674560e4b51c79b",
+        "rev": "7deb7b084d6959f4076bcf0ff4aa0a120f1d31ca",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_3": {
+      "locked": {
+        "lastModified": 1645655918,
+        "narHash": "sha256-ZfbEFRW7o237+A1P7eTKhXje435FCAoe0blj2n20Was=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "77a7a4197740213879b9a1d2e1788c6c8ade4274",
         "type": "github"
       },
       "original": {
@@ -200,17 +307,37 @@
         "type": "indirect"
       }
     },
-    "pre-commit-hooks": {
+    "poetry2nix": {
       "inputs": {
         "flake-utils": "flake-utils_2",
         "nixpkgs": "nixpkgs_2"
       },
       "locked": {
-        "lastModified": 1624971177,
-        "narHash": "sha256-Amf/nBj1E77RmbSSmV+hg6YOpR+rddCbbVgo5C7BS0I=",
+        "lastModified": 1650693998,
+        "narHash": "sha256-rypGV9HND1VsR/DEtD4O3cPcwCJVfIiTKvEbYskQSqg=",
+        "owner": "nix-community",
+        "repo": "poetry2nix",
+        "rev": "8cfd980262181bd3ef15899708ceeb2e3f33958b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-community",
+        "ref": "master",
+        "repo": "poetry2nix",
+        "type": "github"
+      }
+    },
+    "pre-commit-hooks": {
+      "inputs": {
+        "flake-utils": "flake-utils_3",
+        "nixpkgs": "nixpkgs_3"
+      },
+      "locked": {
+        "lastModified": 1649054408,
+        "narHash": "sha256-wz8AH7orqUE4Xog29WMTqOYBs0DMj2wFM8ulrTRVgz0=",
         "owner": "cachix",
         "repo": "pre-commit-hooks.nix",
-        "rev": "397f0713d007250a2c7a745e555fa16c5dc8cadb",
+        "rev": "e5e7b3b542e7f4f96967966a943d7e1c07558042",
         "type": "github"
       },
       "original": {
@@ -219,6 +346,18 @@
         "type": "github"
       }
     },
+    "ptr-poker": {
+      "flake": false,
+      "locked": {
+        "narHash": "sha256-ll3wuUjkhTE8Grcs8LfGpdiuyobrSBmwgjqPOTlrPac=",
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/ptr-poker-0.1.2.8/ptr-poker-0.1.2.8.tar.gz"
+      },
+      "original": {
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/ptr-poker-0.1.2.8/ptr-poker-0.1.2.8.tar.gz"
+      }
+    },
     "retrie": {
       "flake": false,
       "locked": {
@@ -233,21 +372,60 @@
     },
     "root": {
       "inputs": {
+        "aeson-1520": "aeson-1520",
+        "brittany-01312": "brittany-01312",
         "constraints-extras": "constraints-extras",
         "flake-compat": "flake-compat",
         "flake-utils": "flake-utils",
         "fourmolu": "fourmolu",
+        "fourmolu-0300": "fourmolu-0300",
         "ghc-exactprint": "ghc-exactprint",
+        "ghc-exactprint-150": "ghc-exactprint-150",
         "gitignore": "gitignore",
         "hie-bios": "hie-bios",
         "hlint": "hlint",
+        "hlint-34": "hlint-34",
         "implicit-hie-cradle": "implicit-hie-cradle",
         "lsp": "lsp",
         "lsp-test": "lsp-test",
         "lsp-types": "lsp-types",
+        "myst-parser": "myst-parser",
         "nixpkgs": "nixpkgs",
+        "poetry2nix": "poetry2nix",
         "pre-commit-hooks": "pre-commit-hooks",
-        "retrie": "retrie"
+        "ptr-poker": "ptr-poker",
+        "retrie": "retrie",
+        "sphinx_rtd_theme": "sphinx_rtd_theme",
+        "stylish-haskell-01220": "stylish-haskell-01220"
+      }
+    },
+    "sphinx_rtd_theme": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1628276861,
+        "narHash": "sha256-fzqi0QfDSiN8YXtAiWXIoOlyHZQI4V32uOKZjPfWeWY=",
+        "owner": "readthedocs",
+        "repo": "sphinx_rtd_theme",
+        "rev": "34f81daaf52466366c80003db293d50075c1b896",
+        "type": "github"
+      },
+      "original": {
+        "owner": "readthedocs",
+        "repo": "sphinx_rtd_theme",
+        "rev": "34f81daaf52466366c80003db293d50075c1b896",
+        "type": "github"
+      }
+    },
+    "stylish-haskell-01220": {
+      "flake": false,
+      "locked": {
+        "narHash": "sha256-uQIvhz/xRbKLHe9et+tHUVE9To5vt1Pz3+vvDEqJaLI=",
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/stylish-haskell-0.12.2.0/stylish-haskell-0.12.2.0.tar.gz"
+      },
+      "original": {
+        "type": "tarball",
+        "url": "https://hackage.haskell.org/package/stylish-haskell-0.12.2.0/stylish-haskell-0.12.2.0.tar.gz"
       }
     }
   },
diff --git a/flake.nix b/flake.nix
index 1676dbed47..ba822865b0 100644
--- a/flake.nix
+++ b/flake.nix
@@ -35,6 +35,10 @@
       url = "https://hackage.haskell.org/package/lsp-test-0.14.0.2/lsp-test-0.14.0.2.tar.gz";
       flake = false;
     };
+    ghc-exactprint-150 = {
+      url = "https://hackage.haskell.org/package/ghc-exactprint-1.5.0/ghc-exactprint-1.5.0.tar.gz";
+      flake = false;
+    };
     ghc-exactprint = {
       url = "https://hackage.haskell.org/package/ghc-exactprint-1.4.1/ghc-exactprint-1.4.1.tar.gz";
       flake = false;
@@ -51,10 +55,34 @@
       url = "https://hackage.haskell.org/package/fourmolu-0.5.0.1/fourmolu-0.5.0.1.tar.gz";
       flake = false;
     };
+    fourmolu-0300 = {
+      url = "https://hackage.haskell.org/package/fourmolu-0.3.0.0/fourmolu-0.3.0.0.tar.gz";
+      flake = false;
+    };
+    aeson-1520= {
+      url = "https://hackage.haskell.org/package/aeson-1.5.2.0/aeson-1.5.2.0.tar.gz";
+      flake = false;
+    };
+    brittany-01312 = {
+      url = "https://hackage.haskell.org/package/brittany-0.13.1.2/brittany-0.13.1.2.tar.gz";
+      flake = false;
+    };
     hlint = {
       url = "https://hackage.haskell.org/package/hlint-3.3.6/hlint-3.3.6.tar.gz";
       flake = false;
     };
+    hlint-34 = {
+      url = "https://hackage.haskell.org/package/hlint-3.4/hlint-3.4.tar.gz";
+      flake = false;
+    };
+    ptr-poker = {
+      url = "https://hackage.haskell.org/package/ptr-poker-0.1.2.8/ptr-poker-0.1.2.8.tar.gz";
+      flake = false;
+    };
+    stylish-haskell-01220 = {
+      url = "https://hackage.haskell.org/package/stylish-haskell-0.12.2.0/stylish-haskell-0.12.2.0.tar.gz";
+      flake = false;
+    };
     implicit-hie-cradle = {
       url = "https://hackage.haskell.org/package/implicit-hie-cradle-0.3.0.5/implicit-hie-cradle-0.3.0.5.tar.gz";
       flake = false;
@@ -63,11 +91,21 @@
       url = "https://hackage.haskell.org/package/hie-bios-0.9.1/hie-bios-0.9.1.tar.gz";
       flake = false;
     };
+    myst-parser = {
+      url = "github:smunix/MyST-Parser?ref=fix.hls-docutils"; 
+      flake = false;
+    };
+    # For https://github.com/readthedocs/sphinx_rtd_theme/pull/1185, otherwise lists are broken locally
+    sphinx_rtd_theme = {
+      url = "github:readthedocs/sphinx_rtd_theme?rev=34f81daaf52466366c80003db293d50075c1b896";
+      flake = false;
+    };
+    poetry2nix.url = "github:nix-community/poetry2nix/master";
   };
   outputs =
     inputs@{ self, nixpkgs, flake-compat, flake-utils, pre-commit-hooks, gitignore, ... }:
     {
-      overlay = final: prev:
+      overlays.default = final: prev:
         with prev;
         let
           haskellOverrides = hself: hsuper: {
@@ -114,8 +152,6 @@
               github = overrideCabal hsuper.github (drv: { patches = []; });
               # GHCIDE requires hie-bios ^>=0.9.1
               hie-bios = hself.callCabal2nix "hie-bios" inputs.hie-bios {};
-              # We need an older version
-              hiedb = hself.hiedb_0_4_1_0;
 
               lsp = hsuper.callCabal2nix "lsp" inputs.lsp {};
               lsp-types = hsuper.callCabal2nix "lsp-types" inputs.lsp-types {};
@@ -171,7 +207,7 @@
       let
         pkgs = import nixpkgs {
           inherit system;
-          overlays = [ self.overlay ];
+          overlays = [ self.overlays.default inputs.poetry2nix.overlay ];
           config = { allowBroken = true; };
         };
 
@@ -206,29 +242,46 @@
           };
         };
 
-        ghc901Config = (import ./configuration-ghc-901.nix) { inherit pkgs; };
-        ghc921Config = (import ./configuration-ghc-921.nix) { inherit pkgs inputs; };
+        ghc88Config = (import ./configuration-ghc-88.nix) { inherit pkgs inputs; };
+        ghc810Config = (import ./configuration-ghc-810.nix) { inherit pkgs inputs; };
+        ghc902Config = (import ./configuration-ghc-90.nix) { inherit pkgs inputs; };
+        ghc922Config = (import ./configuration-ghc-92.nix) { inherit pkgs inputs; };
 
         # GHC versions
-        ghcDefault = pkgs.hlsHpkgs ("ghc"
-          + pkgs.lib.replaceStrings [ "." ] [ "" ]
-          pkgs.haskellPackages.ghc.version);
-        ghc884 = pkgs.hlsHpkgs "ghc884";
-        ghc8107 = pkgs.hlsHpkgs "ghc8107";
-        ghc901 = ghc901Config.tweakHpkgs (pkgs.hlsHpkgs "ghc901");
-        ghc921 = ghc921Config.tweakHpkgs (pkgs.hlsHpkgs "ghc921");
+        supportedGHCs = let
+          ghcVersion = "ghc" + (pkgs.lib.replaceStrings ["."] [""] pkgs.haskellPackages.ghc.version);
+          cases = {
+            ghc884  = ghc88Config.tweakHpkgs (pkgs.hlsHpkgs "ghc884");
+            ghc8107 = ghc810Config.tweakHpkgs (pkgs.hlsHpkgs "ghc8107");
+            ghc902 = ghc902Config.tweakHpkgs (pkgs.hlsHpkgs "ghc902");
+            ghc922 = ghc922Config.tweakHpkgs (pkgs.hlsHpkgs "ghc922");
+          };
+          in { default = cases."${ghcVersion}"; } // cases;
+
+        ghc884 = supportedGHCs.ghc884;
+        ghc8107 = supportedGHCs.ghc8107;
+        ghc902 = supportedGHCs.ghc902;
+        ghc922 = supportedGHCs.ghc922;
+        ghcDefault = supportedGHCs.default;
 
         # For markdown support
-        myst-parser = pkgs.python3Packages.callPackage ./myst-parser.nix {};
-        sphinx_rtd_theme = pkgs.python3Packages.sphinx_rtd_theme.overrideAttrs (oldAttrs: {
-          # For https://github.com/readthedocs/sphinx_rtd_theme/pull/1185, otherwise lists are broken locally
-          src = pkgs.fetchFromGitHub {
-            owner = "readthedocs";
-            repo = "sphinx_rtd_theme";
-            rev = "34f81daaf52466366c80003db293d50075c1b896";
-            sha256 = "0rkrsvvqr6g2p3v5vq88jhfp5sd0r1jqjh3vc5y26jn30z8s4fkz";
-          };
-        });
+        myst-parser = pkgs.poetry2nix.mkPoetryEnv {
+          projectDir = inputs.myst-parser;
+          python = pkgs.python39;
+          overrides = [ 
+            pkgs.poetry2nix.defaultPoetryOverrides
+          ];
+        };
+        sphinx_rtd_theme = pkgs.poetry2nix.mkPoetryEnv {
+          projectDir = inputs.sphinx_rtd_theme;
+          python = pkgs.python39;
+          overrides = [ 
+            pkgs.poetry2nix.defaultPoetryOverrides
+            (self: super: {
+              docutils = pkgs.python3Packages.callPackage ./docutils.nix {};
+            })
+          ];
+        };
         pythonWithPackages = pkgs.python3.withPackages (ps: [ps.sphinx myst-parser sphinx_rtd_theme ps.pip]);
 
         docs = pkgs.stdenv.mkDerivation {
@@ -270,6 +323,7 @@
             capstone tracy
             # ormolu
             # stylish-haskell
+            pre-commit
             ];
 
 
@@ -280,7 +334,7 @@
             export PATH=$PATH:$HOME/.local/bin
 
             # Enable the shell hooks
-            ${(pre-commit-check ghcDefault).shellHook}
+            ${self.checks.${system}.pre-commit-check.shellHook}
 
             # If the cabal project file is not the default one.
             # Print a warning and generate an alias.
@@ -336,8 +390,8 @@
           haskell-language-server-dev = mkDevShell ghcDefault "cabal.project";
           haskell-language-server-884-dev = mkDevShell ghc884 "cabal.project";
           haskell-language-server-8107-dev = mkDevShell ghc8107 "cabal.project";
-          haskell-language-server-901-dev = mkDevShell ghc901 "cabal-ghc90.project";
-          haskell-language-server-921-dev = mkDevShell ghc921 "cabal-ghc92.project";
+          haskell-language-server-902-dev = mkDevShell ghc902 "cabal.project";
+          haskell-language-server-922-dev = mkDevShell ghc922 "cabal-ghc92.project";
         };
 
         # Developement shell, haskell packages are also provided by nix
@@ -345,21 +399,26 @@
           haskell-language-server-dev-nix = mkDevShellWithNixDeps ghcDefault "cabal.project";
           haskell-language-server-884-dev-nix = mkDevShellWithNixDeps ghc884 "cabal.project";
           haskell-language-server-8107-dev-nix = mkDevShellWithNixDeps ghc8107 "cabal.project";
-          haskell-language-server-901-dev-nix = mkDevShellWithNixDeps ghc901 "cabal-ghc90.project";
-          haskell-language-server-921-dev-nix = mkDevShellWithNixDeps ghc921 "cabal-ghc92.project";
+          haskell-language-server-902-dev-nix = mkDevShellWithNixDeps ghc902 "cabal.project";
+          haskell-language-server-922-dev-nix = mkDevShellWithNixDeps ghc922 "cabal-ghc92.project";
         };
 
         allPackages = {
           haskell-language-server = mkExe ghcDefault;
           haskell-language-server-884 = mkExe ghc884;
           haskell-language-server-8107 = mkExe ghc8107;
-          haskell-language-server-901 = mkExe ghc901;
-          haskell-language-server-921 = mkExe ghc921;
+          haskell-language-server-902 = mkExe ghc902;
+          haskell-language-server-922 = mkExe ghc922;
         };
 
-        devShells = simpleDevShells // nixDevShells;
+        devShells = simpleDevShells // nixDevShells // {
+          default = simpleDevShells.haskell-language-server-dev;
+          inherit (self.checks.${system}.pre-commit-check) shellHook;
+        };
 
         packages = allPackages // {
+          default = allPackages.haskell-language-server;
+
           # See https://github.com/NixOS/nix/issues/5591
           # nix flake cannot build a list/set of derivation in one command.
           # Using a linkFarmFromDrvs, I'm creating a unique entry point to
@@ -377,9 +436,10 @@
           docs = docs;
         };
 
-        defaultPackage = packages.haskell-language-server;
+        checks = { pre-commit-check = pre-commit-check ghcDefault; };
 
-        devShell = devShells.haskell-language-server-dev;
+        devShell = devShells.default;
+        defaultPackage = packages.default;
       });
 
   nixConfig = {
diff --git a/hie-compat/hie-compat.cabal b/hie-compat/hie-compat.cabal
index 13b0cb3ef1..0683c7a628 100644
--- a/hie-compat/hie-compat.cabal
+++ b/hie-compat/hie-compat.cabal
@@ -24,7 +24,7 @@ library
   default-language:    Haskell2010
   build-depends:
      base < 4.17, array, bytestring, containers, directory, filepath, transformers
-  if flag(ghc-lib)
+  if flag(ghc-lib) && impl(ghc < 9)
     build-depends: ghc-lib < 9.0
   else
     build-depends: ghc, ghc-boot