diff --git a/default.nix b/default.nix
index 52c9ea7055..e086158618 100644
--- a/default.nix
+++ b/default.nix
@@ -141,7 +141,23 @@ rec {
 
   # Linting and styling tools.
   style =
-    pkgs.callPackage nix/tools/style.nix { inherit hsie; };
+    let
+      # keep old version of hlint to not deal with linter changes for now
+      nixpkgsVersionPrev = {
+        date = "2021-11-02";
+        rev = "7053541084bf5ce2921ef307e5585d39d7ba8b3f";
+        tarballHash = "1flhh5d4zy43x6060hvzjb5hi5cmc51ivc0nwmija9n8d35kcc4x";
+      };
+
+      nixpkgsPrev =
+        builtins.fetchTarball {
+          url = "https://github.com/nixos/nixpkgs/archive/${nixpkgsVersionPrev.rev}.tar.gz";
+          sha256 = nixpkgsVersionPrev.tarballHash;
+        };
+      pkgsPrev = import nixpkgsPrev { };
+      inherit (pkgsPrev) hlint;
+    in
+    pkgs.callPackage nix/tools/style.nix { inherit hlint hsie; };
 
   # Scripts for running tests.
   tests =
diff --git a/nix/hsie/default.nix b/nix/hsie/default.nix
index f0809c99ae..1f6c2297d7 100644
--- a/nix/hsie/default.nix
+++ b/nix/hsie/default.nix
@@ -28,8 +28,8 @@ let
         mkdir -p $out/bin
         ln -s $hsie $out/bin/$name
       '';
-  bashCompletion =
+  bash-completion =
     runCommand "${name}-bash-completion" { inherit bin name; }
       "$bin/bin/$name --bash-completion-script $bin/bin/$name > $out";
 in
-hsie // { inherit bashCompletion bin; }
+hsie // { inherit bash-completion bin; }
diff --git a/nix/nixpkgs-version.nix b/nix/nixpkgs-version.nix
index 805169bebc..f5f42f5f4a 100644
--- a/nix/nixpkgs-version.nix
+++ b/nix/nixpkgs-version.nix
@@ -1,6 +1,6 @@
 # Pinned version of Nixpkgs, generated with postgrest-nixpkgs-upgrade.
 {
-  date = "2021-11-02";
-  rev = "7053541084bf5ce2921ef307e5585d39d7ba8b3f";
-  tarballHash = "1flhh5d4zy43x6060hvzjb5hi5cmc51ivc0nwmija9n8d35kcc4x";
+  date = "2022-03-30";
+  rev = "9a5aa75d56ad4163521f1692469e6dc54b90068c";
+  tarballHash = "1f3wyldcx1zpyk2q6122mkg16chf9j7swwx1v6f1dg126xz1238f";
 }
diff --git a/nix/overlays/build-toolbox/build-toolbox.nix b/nix/overlays/build-toolbox/build-toolbox.nix
index a170f9a24e..e6b33e12fe 100644
--- a/nix/overlays/build-toolbox/build-toolbox.nix
+++ b/nix/overlays/build-toolbox/build-toolbox.nix
@@ -1,11 +1,11 @@
-# Creates an environment that exposes bashCompletion arguments from all checkedShellScripts
+# Creates an environment that exposes bash-completion arguments from all checkedShellScripts
 { buildEnv }:
 { name
 , tools
 , extra ? { }
 }:
 let
-  bashCompletion = builtins.map (tool: tool.bashCompletion) tools;
+  bash-completion = builtins.map (tool: tool.bash-completion) tools;
 
   env = buildEnv {
     inherit name;
@@ -13,4 +13,4 @@ let
   };
 
 in
-env // { inherit bashCompletion; } // extra
+env // { inherit bash-completion; } // extra
diff --git a/nix/overlays/checked-shell-script/checked-shell-script.nix b/nix/overlays/checked-shell-script/checked-shell-script.nix
index 7de75f5249..e3c382e6d6 100644
--- a/nix/overlays/checked-shell-script/checked-shell-script.nix
+++ b/nix/overlays/checked-shell-script/checked-shell-script.nix
@@ -58,7 +58,7 @@ let
         sed '/_positionals_count + 1/a\\t\t\t\tset -- "''${@:1:1}" "--" "''${@:2}"' -i $out
       '';
 
-  bashCompletion =
+  bash-completion =
     runCommand "${name}-completion" { } (
       ''
         ${argbash}/bin/argbash --type completion --strip all ${argsTemplate}/${name}.m4 > $out
@@ -138,4 +138,4 @@ let
   script =
     runCommand name { inherit bin name; } "ln -s $bin/bin/$name $out";
 in
-script // { inherit bin bashCompletion; }
+script // { inherit bin bash-completion; }
diff --git a/nix/overlays/haskell-packages.nix b/nix/overlays/haskell-packages.nix
index aed8262478..33a5a3cacb 100644
--- a/nix/overlays/haskell-packages.nix
+++ b/nix/overlays/haskell-packages.nix
@@ -41,41 +41,35 @@ let
           }
           { };
 
-      wai-extra =
+      configurator-pg =
         prev.callHackageDirect
           {
-            pkg = "wai-extra";
-            ver = "3.1.8";
-            sha256 = "1ha8sxc2ii7k7xs5nm06wfwqmf4f1p2acp4ya0jnx6yn6551qps4";
+            pkg = "configurator-pg";
+            ver = "0.2.6";
+            sha256 = "sha256-nkamTOpP/w0vQfOXsoQKEstW3n9qyRsv0TocrEerKlU=";
           }
           { };
 
-      wai-logger =
-        prev.callHackageDirect
+      hasql-dynamic-statements =
+        lib.dontCheck (prev.callHackageDirect
           {
-            pkg = "wai-logger";
-            ver = "2.3.7";
-            sha256 = "1d23fdbwbahr3y1vdyn57m1qhljy22pm5cpgb20dy6mlxzdb30xd";
+            pkg = "hasql-dynamic-statements";
+            ver = "0.3.1.1";
+            sha256 = "sha256-jF50GcCtEUV3TN1UsD4LaSBH6arcqfKhxOk+b+c8Bl8=";
           }
-          { };
+          { });
 
-      warp =
+      hasql-implicits =
         lib.dontCheck (prev.callHackageDirect
           {
-            pkg = "warp";
-            ver = "3.3.19";
-            sha256 = "0y3jj4bhviss6ff9lwxki0zbdcl1rb398bk4s80zvfpnpy7p94cx";
+            pkg = "hasql-implicits";
+            ver = "0.1.0.3";
+            sha256 = "sha256-IpAOVHNdXJ53B/fmo+DeNUKiBSS6Bo7Uha/krpMt64g=";
           }
           { });
 
-      hasql-dynamic-statements =
-        lib.dontCheck (lib.unmarkBroken prev.hasql-dynamic-statements);
-
-      hasql-implicits =
-        lib.dontCheck (lib.unmarkBroken prev.hasql-implicits);
-
-      ptr =
-        lib.dontCheck (lib.unmarkBroken prev.ptr);
+      hspec-wai-json =
+        lib.dontCheck (lib.unmarkBroken prev.hspec-wai-json);
     } // extraOverrides final prev;
 in
 {
diff --git a/nix/overlays/postgresql-legacy.nix b/nix/overlays/postgresql-legacy.nix
index 6e3afbdd61..248f9f4248 100644
--- a/nix/overlays/postgresql-legacy.nix
+++ b/nix/overlays/postgresql-legacy.nix
@@ -2,19 +2,18 @@ self: super:
 # Overlay that adds legacy versions of PostgreSQL that are supported by
 # PostgREST.
 {
-  # PostgreSQL 9.5 was removed from Nixpkgs with
-  # https://github.com/NixOS/nixpkgs/commit/72ab382fb6b729b0d654f2c03f5eb25b39f11fbb
+  # PostgreSQL 9.6 was removed from Nixpkgs with
+  # https://github.com/NixOS/nixpkgs/commit/757dd008b2f2926fc0f7688fa8189f930ea47521
   # We pin its parent commit to get the last version that was available.
-  # postgresql_9_5 =
-  #  let
-  #    rev = "55ac7d4580c9ab67848c98cb9519317a1cc399c8";
-  #    tarballHash = "02ffj9f8s1hwhmxj85nx04sv64qb6jm7w0122a1dz9n32fymgklj";
-  #
-  #    pinnedPkgs =
-  #      builtins.fetchTarball {
-  #        url = "https://github.com/nixos/nixpkgs/archive/${rev}.tar.gz";
-  #        sha256 = tarballHash;
-  #      };
-  #  in
-  #  (import pinnedPkgs { }).pkgs.postgresql_9_5;
+  postgresql_9_6 =
+    let
+      rev = "571cbf3d1db477058303cef8754fb85a14e90eb7";
+      tarballHash = "0q74wn418i1bn5sssacmw8ykpmqvzr0s93sj6pbs3rf6bf134fkz";
+      pinnedPkgs =
+        builtins.fetchTarball {
+          url = "https://github.com/nixos/nixpkgs/archive/${rev}.tar.gz";
+          sha256 = tarballHash;
+        };
+    in
+    (import pinnedPkgs { }).pkgs.postgresql_9_6;
 }
diff --git a/nix/patches/default.nix b/nix/patches/default.nix
index 9c9109cd8a..880a8cece9 100644
--- a/nix/patches/default.nix
+++ b/nix/patches/default.nix
@@ -21,4 +21,9 @@
   # See: https://github.com/NixOS/nixpkgs/pull/87879
   nixpkgs-openssl-split-runtime-dependencies-of-static-builds =
     ./nixpkgs-openssl-split-runtime-dependencies-of-static-builds.patch;
+
+  static-haskell-nix-ncurses =
+    ./static-haskell-nix-ncurses.patch;
+  static-haskell-nix-isexecutable =
+    ./static-haskell-nix-isexecutable.patch;
 }
diff --git a/nix/patches/nixpkgs-openssl-split-runtime-dependencies-of-static-builds.patch b/nix/patches/nixpkgs-openssl-split-runtime-dependencies-of-static-builds.patch
index 43b58f8d61..e92f656385 100644
--- a/nix/patches/nixpkgs-openssl-split-runtime-dependencies-of-static-builds.patch
+++ b/nix/patches/nixpkgs-openssl-split-runtime-dependencies-of-static-builds.patch
@@ -2,11 +2,11 @@ diff --git a/pkgs/development/libraries/openssl/default.nix b/pkgs/development/l
 index d4be8cc2428..3979698711f 100644
 --- a/pkgs/development/libraries/openssl/default.nix
 +++ b/pkgs/development/libraries/openssl/default.nix
-@@ -50,9 +50,21 @@ let
+@@ -43,9 +43,21 @@ let
        substituteInPlace crypto/async/arch/async_posix.h \
          --replace '!defined(__ANDROID__) && !defined(__OpenBSD__)' \
                    '!defined(__ANDROID__) && !defined(__OpenBSD__) && 0'
-+    '' + optionalString static
++    '' + lib.optionalString static
 +    # On static builds, the ENGINESDIR will be empty, but its path will be
 +    # compiled into the library. In order to minimize the runtime dependencies
 +    # of packages that statically link openssl, we move it into the OPENSSLDIR,
@@ -17,15 +17,15 @@ index d4be8cc2428..3979698711f 100644
 +                  'ENGINESDIR=$(OPENSSLDIR)/engines-{- $sover_dirname -}'
      '';
  
--    outputs = [ "bin" "dev" "out" "man" ] ++ optional withDocs "doc";
+-    outputs = [ "bin" "dev" "out" "man" ] ++ lib.optional withDocs "doc";
 +    outputs = [ "bin" "dev" "out" "man" ]
-+      ++ optional withDocs "doc"
++      ++ lib.optional withDocs "doc"
 +      # Separate output for the runtime dependencies of the static build.
-+      ++ optional static "etc";
++      ++ lib.optional static "etc";
      setOutputFlags = false;
      separateDebugInfo =
        !stdenv.hostPlatform.isDarwin &&
-@@ -101,7 +113,17 @@ let
+@@ -95,7 +107,17 @@ let
      configureFlags = [
        "shared" # "shared" builds both shared and static libraries
        "--libdir=lib"
@@ -44,7 +44,7 @@ index d4be8cc2428..3979698711f 100644
      ] ++ lib.optionals withCryptodev [
        "-DHAVE_CRYPTODEV"
        "-DUSE_CRYPTODEV_DIGESTS"
-@@ -131,6 +153,9 @@ let
+@@ -126,6 +148,9 @@ let
        if [ -n "$(echo $out/lib/*.so $out/lib/*.dylib $out/lib/*.dll)" ]; then
            rm "$out/lib/"*.a
        fi
@@ -54,7 +54,7 @@ index d4be8cc2428..3979698711f 100644
      '' + lib.optionalString (!stdenv.hostPlatform.isWindows)
        # Fix bin/c_rehash's perl interpreter line
        #
-@@ -152,14 +177,15 @@ let
+@@ -147,14 +172,15 @@ let
        mv $out/include $dev/
  
        # remove dependency on Perl at runtime
diff --git a/nix/patches/static-haskell-nix-isexecutable.patch b/nix/patches/static-haskell-nix-isexecutable.patch
new file mode 100644
index 0000000000..a35adc8853
--- /dev/null
+++ b/nix/patches/static-haskell-nix-isexecutable.patch
@@ -0,0 +1,18 @@
+diff --git a/survey/default.nix b/survey/default.nix
+index 46d8066..5f7950b 100644
+--- a/survey/default.nix
++++ b/survey/default.nix
+@@ -85,10 +85,9 @@ let
+   # Function that tells us if a given Haskell package has an executable.
+   # Pass only Haskell packages to this!
+   # Filter away other stuff with `isProperHaskellPackage` first.
+-  isExecutable = pkg:
+-    (pkgs.haskell.lib.overrideCabal pkg (drv: {
+-      passthru.isExecutable = drv.isExecutable or false;
+-    })).isExecutable;
++  # FIXME postgrest: original fails with our nixpkgs version, we
++  # just hardcode the check to work for a static postgrest build.
++  isExecutable = pkg: pkg.name == "postgrest";
+ 
+   # Turn e.g. `Cabal_1_2_3_4` into `1.2.3.4`.
+   cabalDottedVersion =
diff --git a/nix/patches/static-haskell-nix-ncurses.patch b/nix/patches/static-haskell-nix-ncurses.patch
new file mode 100644
index 0000000000..39c1327412
--- /dev/null
+++ b/nix/patches/static-haskell-nix-ncurses.patch
@@ -0,0 +1,13 @@
+diff --git a/survey/default.nix b/survey/default.nix
+index 46d8066..a47f214 100644
+--- a/survey/default.nix
++++ b/survey/default.nix
+@@ -1519,7 +1519,7 @@ let
+                   [
+                     "--enable-executable-static" # requires `useFixedCabal`
+                     # `enableShared` seems to be required to avoid `recompile with -fPIC` errors on some packages.
+-                    "--extra-lib-dirs=${final.ncurses.override { enableStatic = true; enableShared = true; }}/lib"
++                    "--extra-lib-dirs=${final.ncurses}/lib"
+                   ]
+                   # TODO Figure out why this and the below libffi are necessary.
+                   #      `working` and `workingStackageExecutables` don't seem to need that,
diff --git a/nix/static-haskell-package.nix b/nix/static-haskell-package.nix
index 57d5e6a1f5..1c353970ac 100644
--- a/nix/static-haskell-package.nix
+++ b/nix/static-haskell-package.nix
@@ -17,7 +17,8 @@ let
     patches.applyPatches "patched-static-haskell-nix"
       static-haskell-nix
       [
-        # No patches currently required.
+        patches.static-haskell-nix-ncurses
+        patches.static-haskell-nix-isexecutable
       ];
 
   patchedNixpkgs =
diff --git a/nix/tools/withTools.nix b/nix/tools/withTools.nix
index 33c38681de..e070d112ce 100644
--- a/nix/tools/withTools.nix
+++ b/nix/tools/withTools.nix
@@ -1,4 +1,4 @@
-{ bashCompletion
+{ bash-completion
 , buildToolbox
 , cabal-install
 , checkedShellScript
diff --git a/postgrest.cabal b/postgrest.cabal
index 543be2dc91..2c6fb8eaa2 100644
--- a/postgrest.cabal
+++ b/postgrest.cabal
@@ -71,7 +71,7 @@ library
   build-depends:      base                      >= 4.9 && < 4.16
                     , HTTP                      >= 4000.3.7 && < 4000.4
                     , Ranged-sets               >= 0.3 && < 0.5
-                    , aeson                     >= 1.4.7 && < 1.6
+                    , aeson                     >= 2.0.3 && < 2.1
                     , auto-update               >= 0.1.4 && < 0.2
                     , base64-bytestring         >= 1 && < 1.3
                     , bytestring                >= 0.10.8 && < 0.11
@@ -83,8 +83,8 @@ library
                     , cookie                    >= 0.4.2 && < 0.5
                     , either                    >= 4.4.1 && < 5.1
                     , gitrev                    >= 1.2 && < 1.4
-                    , hasql                     >= 1.4 && < 1.5
-                    , hasql-dynamic-statements  == 0.3.1
+                    , hasql                     >= 1.4 && < 1.6
+                    , hasql-dynamic-statements  >= 0.3.1 && < 0.4
                     , hasql-notifications       >= 0.1 && < 0.3
                     , hasql-pool                >= 0.5 && < 0.6
                     , hasql-transaction         >= 1.0.1 && < 1.1
@@ -92,7 +92,7 @@ library
                     , http-types                >= 0.12.2 && < 0.13
                     , insert-ordered-containers >= 0.2.2 && < 0.3
                     , interpolatedstring-perl6  >= 1 && < 1.1
-                    , jose                      >= 0.8.1 && < 0.9
+                    , jose                      >= 0.8.5.1 && < 0.10
                     , lens                      >= 4.14 && < 5.1
                     , lens-aeson                >= 1.0.1 && < 1.2
                     , mtl                       >= 2.2.2 && < 2.3
@@ -104,7 +104,7 @@ library
                     , regex-tdfa                >= 1.2.2 && < 1.4
                     , retry                     >= 0.7.4 && < 0.10
                     , scientific                >= 0.3.4 && < 0.4
-                    , swagger2                  >= 2.4 && < 2.7
+                    , swagger2                  >= 2.4 && < 2.9
                     , text                      >= 1.2.2 && < 1.3
                     , time                      >= 1.6 && < 1.11
                     , unordered-containers      >= 0.2.8 && < 0.3
@@ -113,6 +113,11 @@ library
                     , wai                       >= 3.2.1 && < 3.3
                     , wai-cors                  >= 0.2.5 && < 0.3
                     , wai-extra                 >= 3.1.8 && < 3.2
+                    -- We already depend on wai-logger >= 2.3.7 indirectly via wai-extra,
+                    -- but we want to depend on 2.4.0 which fixes 'unknownSocket' log output
+                    -- for unix sockets; this is tested in test/io/test_io.py. See
+                    -- https://github.com/kazu-yamamoto/logger/commit/3a71ca70afdbb93d4ecf0083eeba1fbbbcab3fc3
+                    , wai-logger                >= 2.4.0
                     , warp                      >= 3.3.19 && < 3.4
                       -- -fno-spec-constr may help keep compile time memory use in check,
                       --   see https://gitlab.haskell.org/ghc/ghc/issues/16017#note_219304
@@ -206,7 +211,7 @@ test-suite spec
                       SpecHelper
                       TestTypes
   build-depends:      base              >= 4.9 && < 4.16
-                    , aeson             >= 1.4.7 && < 1.6
+                    , aeson             >= 2.0.3 && < 2.1
                     , aeson-qq          >= 0.8.1 && < 0.9
                     , async             >= 2.1.1 && < 2.3
                     , auto-update       >= 0.1.4 && < 0.2
@@ -249,14 +254,14 @@ test-suite querycost
   main-is:            QueryCost.hs
   other-modules:      SpecHelper
   build-depends:      base              >= 4.9 && < 4.16
-                    , aeson             >= 1.4.7 && < 1.6
+                    , aeson             >= 2.0.3 && < 2.1
                     , base64-bytestring >= 1 && < 1.3
                     , bytestring        >= 0.10.8 && < 0.11
                     , case-insensitive  >= 1.2 && < 1.3
                     , containers        >= 0.5.7 && < 0.7
                     , contravariant     >= 1.4 && < 1.6
-                    , hasql             >= 1.4 && < 1.5
-                    , hasql-dynamic-statements  == 0.3.1
+                    , hasql             >= 1.4 && < 1.6
+                    , hasql-dynamic-statements >= 0.3.1 && < 0.4
                     , hasql-pool        >= 0.5 && < 0.6
                     , hasql-transaction >= 1.0.1 && < 1.1
                     , heredoc           >= 0.2 && < 0.3
diff --git a/shell.nix b/shell.nix
index 1eb663765c..a073982503 100644
--- a/shell.nix
+++ b/shell.nix
@@ -48,14 +48,14 @@ lib.overrideDerivation postgrest.env (
       ''
         export HISTFILE=.history
 
-        source ${pkgs.bashCompletion}/etc/profile.d/bash_completion.sh
+        source ${pkgs.bash-completion}/etc/profile.d/bash_completion.sh
         source ${pkgs.git}/share/git/contrib/completion/git-completion.bash
-        source ${postgrest.hsie.bashCompletion}
+        source ${postgrest.hsie.bash-completion}
 
       ''
       + builtins.concatStringsSep "\n" (
-        builtins.map (bashCompletion: "source ${bashCompletion}") (
-          builtins.concatLists (builtins.map (toolbox: toolbox.bashCompletion) toolboxes)
+        builtins.map (bash-completion: "source ${bash-completion}") (
+          builtins.concatLists (builtins.map (toolbox: toolbox.bash-completion) toolboxes)
         )
       );
   }
diff --git a/src/PostgREST/App.hs b/src/PostgREST/App.hs
index b5d9f59bd4..b4555f5b0c 100644
--- a/src/PostgREST/App.hs
+++ b/src/PostgREST/App.hs
@@ -28,7 +28,7 @@ import System.Posix.Types       (FileMode)
 
 import qualified Data.ByteString.Char8           as BS
 import qualified Data.ByteString.Lazy            as LBS
-import qualified Data.HashMap.Strict             as M
+import qualified Data.HashMap.Strict             as HM
 import qualified Data.Set                        as S
 import qualified Hasql.DynamicStatements.Snippet as SQL (Snippet)
 import qualified Hasql.Pool                      as SQL
@@ -314,7 +314,7 @@ handleCreate identifier@QualifiedIdentifier{..} context@RequestContext{..} = do
   let
     ApiRequest{..} = ctxApiRequest
     pkCols = if iPreferRepresentation /= None || isJust iPreferResolution
-      then maybe mempty tablePKCols $ M.lookup identifier $ dbTables ctxDbStructure
+      then maybe mempty tablePKCols $ HM.lookup identifier $ dbTables ctxDbStructure
       else mempty
 
   WriteQueryResult{..} <- writeQuery MutationCreate identifier True pkCols context
@@ -371,7 +371,7 @@ handleUpdate identifier context@(RequestContext _ _ ApiRequest{..} _) = do
 
 handleSingleUpsert :: QualifiedIdentifier -> RequestContext-> DbHandler Wai.Response
 handleSingleUpsert identifier context@(RequestContext _ ctxDbStructure ApiRequest{..} _) = do
-  let pkCols = maybe mempty tablePKCols $ M.lookup identifier $ dbTables ctxDbStructure
+  let pkCols = maybe mempty tablePKCols $ HM.lookup identifier $ dbTables ctxDbStructure
 
   WriteQueryResult{..} <- writeQuery MutationSingleUpsert identifier False pkCols context
 
@@ -419,7 +419,7 @@ handleInfo identifier RequestContext{..} =
     Nothing ->
       throwError Error.NotFound
   where
-    tbl = M.lookup identifier (dbTables ctxDbStructure)
+    tbl = HM.lookup identifier (dbTables ctxDbStructure)
     allOrigins = ("Access-Control-Allow-Origin", "*")
     allowH table =
       ( HTTP.hAllow
@@ -489,8 +489,8 @@ handleOpenApi headersOnly tSchema (RequestContext conf@AppConfig{..} dbStructure
            <*> SQL.statement tSchema (DbStructure.schemaDescription configDbPreparedStatements)
       OAIgnorePriv ->
         OpenAPI.encode conf dbStructure
-              (M.filterWithKey (\(QualifiedIdentifier sch _) _ ->  sch == tSchema) $ DbStructure.dbTables dbStructure)
-              (M.filterWithKey (\(QualifiedIdentifier sch _) _ ->  sch == tSchema) $ DbStructure.dbProcs dbStructure)
+              (HM.filterWithKey (\(QualifiedIdentifier sch _) _ ->  sch == tSchema) $ DbStructure.dbTables dbStructure)
+              (HM.filterWithKey (\(QualifiedIdentifier sch _) _ ->  sch == tSchema) $ DbStructure.dbProcs dbStructure)
           <$> SQL.statement tSchema (DbStructure.schemaDescription configDbPreparedStatements)
       OADisabled ->
         pure mempty
diff --git a/src/PostgREST/Auth.hs b/src/PostgREST/Auth.hs
index 093300d018..d14c50ff47 100644
--- a/src/PostgREST/Auth.hs
+++ b/src/PostgREST/Auth.hs
@@ -20,9 +20,10 @@ module PostgREST.Auth
 
 import qualified Crypto.JWT                      as JWT
 import qualified Data.Aeson                      as JSON
+import qualified Data.Aeson.Key                  as K
+import qualified Data.Aeson.KeyMap               as KM
 import qualified Data.Aeson.Types                as JSON
 import qualified Data.ByteString.Lazy.Char8      as LBS
-import qualified Data.HashMap.Strict             as M
 import qualified Data.Text.Encoding              as T
 import qualified Data.Vault.Lazy                 as Vault
 import qualified Data.Vector                     as V
@@ -45,7 +46,7 @@ import Protolude
 
 
 data AuthResult = AuthResult
-  { authClaims :: M.HashMap Text JSON.Value
+  { authClaims :: KM.KeyMap JSON.Value
   , authRole   :: Text
   }
 
@@ -78,13 +79,13 @@ parseClaims AppConfig{..} jclaims@(JSON.Object mclaims) = do
   role <- liftEither . maybeToRight JwtTokenRequired $
     unquoted <$> walkJSPath (Just jclaims) configJwtRoleClaimKey <|> configDbAnonRole
   return AuthResult
-           { authClaims = mclaims & M.insert "role" (JSON.toJSON role)
+           { authClaims = mclaims & KM.insert "role" (JSON.toJSON role)
            , authRole = role
            }
   where
     walkJSPath :: Maybe JSON.Value -> JSPath -> Maybe JSON.Value
     walkJSPath x                      []                = x
-    walkJSPath (Just (JSON.Object o)) (JSPKey key:rest) = walkJSPath (M.lookup key o) rest
+    walkJSPath (Just (JSON.Object o)) (JSPKey key:rest) = walkJSPath (KM.lookup (K.fromText key) o) rest
     walkJSPath (Just (JSON.Array ar)) (JSPIdx idx:rest) = walkJSPath (ar V.!? idx) rest
     walkJSPath _                      _                 = Nothing
 
@@ -92,7 +93,7 @@ parseClaims AppConfig{..} jclaims@(JSON.Object mclaims) = do
     unquoted (JSON.String t) = t
     unquoted v = T.decodeUtf8 . LBS.toStrict $ JSON.encode v
 -- impossible case - just added to please -Wincomplete-patterns
-parseClaims _ _ = return AuthResult { authClaims = M.empty, authRole = mempty }
+parseClaims _ _ = return AuthResult { authClaims = KM.empty, authRole = mempty }
 
 -- | Validate authorization header.
 --   Parse and store JWT claims for future use in the request.
diff --git a/src/PostgREST/DbStructure.hs b/src/PostgREST/DbStructure.hs
index 33e3b20982..6a2a5b583a 100644
--- a/src/PostgREST/DbStructure.hs
+++ b/src/PostgREST/DbStructure.hs
@@ -27,7 +27,7 @@ module PostgREST.DbStructure
   ) where
 
 import qualified Data.Aeson          as JSON
-import qualified Data.HashMap.Strict as M
+import qualified Data.HashMap.Strict as HM
 import qualified Data.Set            as S
 import qualified Hasql.Decoders      as HD
 import qualified Hasql.Encoders      as HE
@@ -100,16 +100,16 @@ queryDbStructure schemas extraSearchPath prepared = do
     , dbProcs = procs
     }
   where
-    relsToMap = map sort . M.fromListWith (++) . map ((\(x, fSch, y) -> ((x, fSch), [y])) . addKey)
+    relsToMap = map sort . HM.fromListWith (++) . map ((\(x, fSch, y) -> ((x, fSch), [y])) . addKey)
     addKey rel = (relTable rel, qiSchema $ relForeignTable rel, rel)
 
 -- | Remove db objects that belong to an internal schema(not exposed through the API) from the DbStructure.
 removeInternal :: [Schema] -> DbStructure -> DbStructure
 removeInternal schemas dbStruct =
   DbStructure {
-      dbTables        = M.filterWithKey (\(QualifiedIdentifier sch _) _ -> sch `elem` schemas) $ dbTables dbStruct
+      dbTables        = HM.filterWithKey (\(QualifiedIdentifier sch _) _ -> sch `elem` schemas) $ dbTables dbStruct
     , dbRelationships = filter (\r -> qiSchema (relForeignTable r) `elem` schemas && not (hasInternalJunction r)) <$>
-                        M.filterWithKey (\(QualifiedIdentifier sch _, _) _ -> sch `elem` schemas ) (dbRelationships dbStruct)
+                        HM.filterWithKey (\(QualifiedIdentifier sch _, _) _ -> sch `elem` schemas ) (dbRelationships dbStruct)
     , dbProcs         = dbProcs dbStruct -- procs are only obtained from the exposed schemas, no need to filter them.
     }
   where
@@ -119,7 +119,7 @@ removeInternal schemas dbStruct =
 
 decodeTables :: HD.Result TablesMap
 decodeTables =
- M.fromList . map (\tbl@Table{tableSchema, tableName} -> (QualifiedIdentifier tableSchema tableName, tbl)) <$> HD.rowList tblRow
+ HM.fromList . map (\tbl@Table{tableSchema, tableName} -> (QualifiedIdentifier tableSchema tableName, tbl)) <$> HD.rowList tblRow
  where
   tblRow = Table
     <$> column HD.text
@@ -176,7 +176,7 @@ viewKeyDepFromRow (s1,t1,s2,v2,cons,consType,sCols) = ViewKeyDependency (Qualifi
 decodeProcs :: HD.Result ProcsMap
 decodeProcs =
   -- Duplicate rows for a function means they're overloaded, order these by least args according to ProcDescription Ord instance
-  map sort . M.fromListWith (++) . map ((\(x,y) -> (x, [y])) . addKey) <$> HD.rowList procRow
+  map sort . HM.fromListWith (++) . map ((\(x,y) -> (x, [y])) . addKey) <$> HD.rowList procRow
   where
     procRow = ProcDescription
               <$> column HD.text
@@ -385,7 +385,7 @@ addM2MRels :: TablesMap -> [Relationship] -> [Relationship]
 addM2MRels tbls rels = rels ++ catMaybes
   [ let
       jtCols = S.fromList $ (fst <$> cols) ++ (fst <$> fcols)
-      pkCols = S.fromList $ maybe mempty tablePKCols $ M.lookup jt1 tbls
+      pkCols = S.fromList $ maybe mempty tablePKCols $ HM.lookup jt1 tbls
     in if S.isSubsetOf jtCols pkCols
       then Just $ Relationship t ft (t == ft) (M2M $ Junction jt1 cons1 cons2 (swap <$> cols) (swap <$> fcols)) tblIsView fTblisView
       else Nothing
diff --git a/src/PostgREST/DbStructure/Proc.hs b/src/PostgREST/DbStructure/Proc.hs
index 3ec5817a9d..a62f436afb 100644
--- a/src/PostgREST/DbStructure/Proc.hs
+++ b/src/PostgREST/DbStructure/Proc.hs
@@ -15,7 +15,7 @@ module PostgREST.DbStructure.Proc
   ) where
 
 import qualified Data.Aeson          as JSON
-import qualified Data.HashMap.Strict as M
+import qualified Data.HashMap.Strict as HM
 
 import PostgREST.DbStructure.Identifiers (QualifiedIdentifier (..),
                                           Schema, TableName)
@@ -66,7 +66,7 @@ instance Ord ProcDescription where
 
 -- | A map of all procs, all of which can be overloaded(one entry will have more than one ProcDescription).
 -- | It uses a HashMap for a faster lookup.
-type ProcsMap = M.HashMap QualifiedIdentifier [ProcDescription]
+type ProcsMap = HM.HashMap QualifiedIdentifier [ProcDescription]
 
 procReturnsScalar :: ProcDescription -> Bool
 procReturnsScalar proc = case proc of
diff --git a/src/PostgREST/DbStructure/Relationship.hs b/src/PostgREST/DbStructure/Relationship.hs
index 0a50c9741e..37f839dbcb 100644
--- a/src/PostgREST/DbStructure/Relationship.hs
+++ b/src/PostgREST/DbStructure/Relationship.hs
@@ -9,7 +9,7 @@ module PostgREST.DbStructure.Relationship
   ) where
 
 import qualified Data.Aeson          as JSON
-import qualified Data.HashMap.Strict as M
+import qualified Data.HashMap.Strict as HM
 
 import PostgREST.DbStructure.Identifiers (FieldName,
                                           QualifiedIdentifier, Schema)
@@ -53,4 +53,4 @@ data Junction = Junction
   deriving (Eq, Ord, Generic, JSON.ToJSON)
 
 -- | Key based on the source table and the foreign table schema
-type RelationshipsMap = M.HashMap (QualifiedIdentifier, Schema)  [Relationship]
+type RelationshipsMap = HM.HashMap (QualifiedIdentifier, Schema)  [Relationship]
diff --git a/src/PostgREST/DbStructure/Table.hs b/src/PostgREST/DbStructure/Table.hs
index 3c6ab5a201..31a0770dd3 100644
--- a/src/PostgREST/DbStructure/Table.hs
+++ b/src/PostgREST/DbStructure/Table.hs
@@ -8,7 +8,7 @@ module PostgREST.DbStructure.Table
   ) where
 
 import qualified Data.Aeson          as JSON
-import qualified Data.HashMap.Strict as M
+import qualified Data.HashMap.Strict as HM
 
 import PostgREST.DbStructure.Identifiers (FieldName,
                                           QualifiedIdentifier (..),
@@ -46,4 +46,4 @@ data Column = Column
   }
   deriving (Eq, Show, Ord, Generic, JSON.ToJSON)
 
-type TablesMap = M.HashMap QualifiedIdentifier Table
+type TablesMap = HM.HashMap QualifiedIdentifier Table
diff --git a/src/PostgREST/GucHeader.hs b/src/PostgREST/GucHeader.hs
index 23f9db3904..2deba6999e 100644
--- a/src/PostgREST/GucHeader.hs
+++ b/src/PostgREST/GucHeader.hs
@@ -5,8 +5,9 @@ module PostgREST.GucHeader
   ) where
 
 import qualified Data.Aeson           as JSON
+import qualified Data.Aeson.Key       as K
+import qualified Data.Aeson.KeyMap    as KM
 import qualified Data.CaseInsensitive as CI
-import qualified Data.HashMap.Strict  as M
 
 import Network.HTTP.Types.Header (Header)
 
@@ -21,8 +22,8 @@ newtype GucHeader = GucHeader (CI.CI ByteString, ByteString)
 
 instance JSON.FromJSON GucHeader where
   parseJSON (JSON.Object o) =
-    case M.toList o of
-      [(k, JSON.String s)] -> pure $ GucHeader (CI.mk $ toUtf8 k, toUtf8 s)
+    case KM.toList o of
+      [(k, JSON.String s)] -> pure $ GucHeader (CI.mk $ toUtf8 $ K.toText k, toUtf8 s)
       _ -> mzero
   parseJSON _ = mzero
 
diff --git a/src/PostgREST/Middleware.hs b/src/PostgREST/Middleware.hs
index a32ee0808f..507202d225 100644
--- a/src/PostgREST/Middleware.hs
+++ b/src/PostgREST/Middleware.hs
@@ -10,8 +10,10 @@ module PostgREST.Middleware
   ) where
 
 import qualified Data.Aeson                        as JSON
+import qualified Data.Aeson.Key                    as K
+import qualified Data.Aeson.KeyMap                 as KM
 import qualified Data.ByteString.Lazy.Char8        as LBS
-import qualified Data.HashMap.Strict               as M
+import qualified Data.HashMap.Strict               as HM
 import qualified Data.Text                         as T
 import qualified Data.Text.Encoding                as T
 import qualified Hasql.Decoders                    as HD
@@ -38,7 +40,7 @@ import PostgREST.Request.Preferences
 import Protolude
 
 -- | Runs local(transaction scoped) GUCs for every request, plus the pre-request function
-runPgLocals :: AppConfig   -> M.HashMap Text JSON.Value -> Text ->
+runPgLocals :: AppConfig   -> KM.KeyMap JSON.Value -> Text ->
                (ApiRequest -> ExceptT Error SQL.Transaction Wai.Response) ->
                ApiRequest  -> ByteString -> PgVersion -> ExceptT Error SQL.Transaction Wai.Response
 runPgLocals conf claims role app req jsonDbS actualPgVersion = do
@@ -57,7 +59,7 @@ runPgLocals conf claims role app req jsonDbS actualPgVersion = do
                    then setConfigLocal "request.cookie." <$> iCookies req
                    else setConfigLocalJson "request.cookies" (iCookies req)
     claimsSql = if usesLegacyGucs
-                  then setConfigLocal "request.jwt.claim." <$> [(toUtf8 c, toUtf8 $ unquoted v) | (c,v) <- M.toList claims]
+                  then setConfigLocal "request.jwt.claim." <$> [(toUtf8 $ K.toText c, toUtf8 $ unquoted v) | (c,v) <- KM.toList claims]
                   else [setConfigLocal mempty ("request.jwt.claims", LBS.toStrict $ JSON.encode claims)]
     roleSql = [setConfigLocal mempty ("role", toUtf8 role)]
     appSettingsSql = setConfigLocal mempty <$> (join bimap toUtf8 <$> configAppSettings conf)
@@ -116,6 +118,6 @@ setConfigLocalJson :: ByteString -> [(ByteString, ByteString)] -> [SQL.Snippet]
 setConfigLocalJson prefix keyVals = [setConfigLocal mempty (prefix, gucJsonVal keyVals)]
   where
     gucJsonVal :: [(ByteString, ByteString)] -> ByteString
-    gucJsonVal = LBS.toStrict . JSON.encode . M.fromList . arrayByteStringToText
+    gucJsonVal = LBS.toStrict . JSON.encode . HM.fromList . arrayByteStringToText
     arrayByteStringToText :: [(ByteString, ByteString)] -> [(Text,Text)]
     arrayByteStringToText keyVal = (T.decodeUtf8 *** T.decodeUtf8) <$> keyVal
diff --git a/src/PostgREST/OpenAPI.hs b/src/PostgREST/OpenAPI.hs
index 0a446adff7..71363046f7 100644
--- a/src/PostgREST/OpenAPI.hs
+++ b/src/PostgREST/OpenAPI.hs
@@ -9,7 +9,7 @@ module PostgREST.OpenAPI (encode) where
 import qualified Data.Aeson            as JSON
 import qualified Data.ByteString.Char8 as BS
 import qualified Data.ByteString.Lazy  as LBS
-import qualified Data.HashMap.Strict   as M
+import qualified Data.HashMap.Strict   as HM
 import qualified Data.HashSet.InsOrd   as Set
 import qualified Data.Text             as T
 import qualified Data.Text.Encoding    as T
@@ -41,13 +41,13 @@ import PostgREST.ContentType
 
 import Protolude hiding (Proxy, get)
 
-encode :: AppConfig -> DbStructure -> TablesMap -> M.HashMap k [ProcDescription] -> Maybe Text -> LBS.ByteString
+encode :: AppConfig -> DbStructure -> TablesMap -> HM.HashMap k [ProcDescription] -> Maybe Text -> LBS.ByteString
 encode conf dbStructure tables procs schemaDescription =
   JSON.encode $
     postgrestSpec
       (dbRelationships dbStructure)
-      (concat $ M.elems procs)
-      (snd <$> M.toList tables)
+      (concat $ HM.elems procs)
+      (snd <$> HM.toList tables)
       (proxyUri conf)
       schemaDescription
 
@@ -100,7 +100,7 @@ makeProperty tbl rels col = (colName col, Inline s)
         rel = find (\case
           Relationship{relCardinality=(M2O _ relColumns)} -> [colName col] == (fst <$> relColumns)
           _                                               -> False
-          ) $ fromMaybe mempty $ M.lookup (QualifiedIdentifier (tableSchema tbl) (tableName tbl), tableSchema tbl) rels
+          ) $ fromMaybe mempty $ HM.lookup (QualifiedIdentifier (tableSchema tbl) (tableName tbl), tableSchema tbl) rels
         fCol = (headMay . (\r -> snd <$> relColumns (relCardinality r)) =<< rel)
         fTbl = qiName . relForeignTable <$> rel
         fTblCol = (,) <$> fTbl <*> fCol
diff --git a/src/PostgREST/Request/ApiRequest.hs b/src/PostgREST/Request/ApiRequest.hs
index ef82ba25e4..8dc4c5d899 100644
--- a/src/PostgREST/Request/ApiRequest.hs
+++ b/src/PostgREST/Request/ApiRequest.hs
@@ -18,13 +18,16 @@ module PostgREST.Request.ApiRequest
   ) where
 
 import qualified Data.Aeson            as JSON
+import qualified Data.Aeson.Key        as K
+import qualified Data.Aeson.KeyMap     as KM
 import qualified Data.ByteString.Char8 as BS
 import qualified Data.ByteString.Lazy  as LBS
 import qualified Data.CaseInsensitive  as CI
 import qualified Data.Csv              as CSV
-import qualified Data.HashMap.Strict   as M
+import qualified Data.HashMap.Strict   as HM
 import qualified Data.List             as L
 import qualified Data.List.NonEmpty    as NonEmptyList
+import qualified Data.Map.Strict       as M
 import qualified Data.Set              as S
 import qualified Data.Text.Encoding    as T
 import qualified Data.Vector           as V
@@ -129,10 +132,10 @@ toRpcParamValue proc (k, v) | prmIsVariadic k = (k, Variadic [v])
 jsonRpcParams :: ProcDescription -> [(Text, Text)] -> Payload
 jsonRpcParams proc prms =
   if not $ pdHasVariadic proc then -- if proc has no variadic param, save steps and directly convert to json
-    ProcessedJSON (JSON.encode $ M.fromList $ second JSON.toJSON <$> prms) (S.fromList $ fst <$> prms)
+    ProcessedJSON (JSON.encode $ HM.fromList $ second JSON.toJSON <$> prms) (S.fromList $ fst <$> prms)
   else
-    let paramsMap = M.fromListWith mergeParams $ toRpcParamValue proc <$> prms in
-    ProcessedJSON (JSON.encode paramsMap) (S.fromList $ M.keys paramsMap)
+    let paramsMap = HM.fromListWith mergeParams $ toRpcParamValue proc <$> prms in
+    ProcessedJSON (JSON.encode paramsMap) (S.fromList $ HM.keys paramsMap)
   where
     mergeParams :: RpcParamValue -> RpcParamValue -> RpcParamValue
     mergeParams (Variadic a) (Variadic b) = Variadic $ b ++ a
@@ -153,7 +156,7 @@ targetToJsonRpcParams target params =
 -}
 data ApiRequest = ApiRequest {
     iAction               :: Action                           -- ^ Similar but not identical to HTTP verb, e.g. Create/Invoke both POST
-  , iRange                :: M.HashMap Text NonnegRange       -- ^ Requested range of rows within response
+  , iRange                :: HM.HashMap Text NonnegRange      -- ^ Requested range of rows within response
   , iTopLevelRange        :: NonnegRange                      -- ^ Requested range of rows from the top level
   , iTarget               :: Target                           -- ^ The target, be it calling a proc or accessing a table
   , iPayload              :: Maybe Payload                    -- ^ Data sent by client and used for mutation actions
@@ -252,13 +255,13 @@ apiRequest conf@AppConfig{..} dbStructure req reqBody queryparams@QueryParams{..
       json <- csvToJson <$> first BS.pack (CSV.decodeByName reqBody)
       note "All lines must have same number of fields" $ payloadAttributes (JSON.encode json) json
     (CTUrlEncoded, _) ->
-      let paramsMap = M.fromList $ (T.decodeUtf8 *** JSON.String . T.decodeUtf8) <$> parseSimpleQuery (LBS.toStrict reqBody) in
-      Right $ ProcessedJSON (JSON.encode paramsMap) $ S.fromList (M.keys paramsMap)
+      let paramsMap = HM.fromList $ (T.decodeUtf8 *** JSON.String . T.decodeUtf8) <$> parseSimpleQuery (LBS.toStrict reqBody) in
+      Right $ ProcessedJSON (JSON.encode paramsMap) $ S.fromList (HM.keys paramsMap)
     (CTTextPlain, True) -> Right $ RawPay reqBody
     (CTTextXML, True) -> Right $ RawPay reqBody
     (CTOctetStream, True) -> Right $ RawPay reqBody
     (ct, _) -> Left $ "Content-Type not acceptable: " <> ContentType.toMime ct
-  topLevelRange = fromMaybe allRange $ M.lookup "limit" ranges -- if no limit is specified, get all the request rows
+  topLevelRange = fromMaybe allRange $ HM.lookup "limit" ranges -- if no limit is specified, get all the request rows
   action =
     case method of
       -- The HEAD method is identical to GET except that the server MUST NOT return a message-body in the response
@@ -335,12 +338,12 @@ apiRequest conf@AppConfig{..} dbStructure req reqBody queryparams@QueryParams{..
   lookupHeader    = flip lookup hdrs
   Preferences.Preferences{..} = Preferences.fromHeaders hdrs
   headerRange = rangeRequested hdrs
-  limitRange = fromMaybe allRange (M.lookup "limit" qsRanges)
+  limitRange = fromMaybe allRange (HM.lookup "limit" qsRanges)
   headerAndLimitRange = rangeIntersection headerRange limitRange
 
   -- Bypass all the ranges and send only the limit zero range (0 <= x <= -1) if
   -- limit=0 is present in the query params (not allowed for the Range header)
-  ranges = M.insert "limit" (if hasLimitZero limitRange then limitZeroRange else headerAndLimitRange) qsRanges
+  ranges = HM.insert "limit" (if hasLimitZero limitRange then limitZeroRange else headerAndLimitRange) qsRanges
   -- The only emptyRange allowed is the limit zero range
   isInvalidRange = topLevelRange == emptyRange && not (hasLimitZero limitRange)
 
@@ -357,7 +360,7 @@ mutuallyAgreeable sProduces cAccepts =
      then listToMaybe sProduces
      else exact
 
-type CsvData = V.Vector (M.HashMap Text LBS.ByteString)
+type CsvData = V.Vector (M.Map Text LBS.ByteString)
 
 {-|
   Converts CSV like
@@ -375,7 +378,7 @@ csvToJson :: (CSV.Header, CsvData) -> JSON.Value
 csvToJson (_, vals) =
   JSON.Array $ V.map rowToJsonObj vals
  where
-  rowToJsonObj = JSON.Object .
+  rowToJsonObj = JSON.Object . KM.fromMapText .
     M.map (\str ->
         if str == "NULL"
           then JSON.Null
@@ -389,9 +392,9 @@ payloadAttributes raw json =
     JSON.Array arr ->
       case arr V.!? 0 of
         Just (JSON.Object o) ->
-          let canonicalKeys = S.fromList $ M.keys o
+          let canonicalKeys = S.fromList $ K.toText <$> KM.keys o
               areKeysUniform = all (\case
-                JSON.Object x -> S.fromList (M.keys x) == canonicalKeys
+                JSON.Object x -> S.fromList (K.toText <$> KM.keys x) == canonicalKeys
                 _ -> False) arr in
           if areKeysUniform
             then Just $ ProcessedJSON raw canonicalKeys
@@ -399,7 +402,7 @@ payloadAttributes raw json =
         Just _ -> Nothing
         Nothing -> Just emptyPJArray
 
-    JSON.Object o -> Just $ ProcessedJSON raw (S.fromList $ M.keys o)
+    JSON.Object o -> Just $ ProcessedJSON raw (S.fromList $ K.toText <$> KM.keys o)
 
     -- truncate everything else to an empty array.
     _ -> Just emptyPJArray
@@ -449,7 +452,7 @@ findProc qi argumentsKeys paramsAsSingleObject allProcs contentType isInvPost =
     ([proc], _)  -> Right proc
     (procs, _)   -> Left $ AmbiguousRpc (toList procs)
   where
-    matchProc = overloadedProcPartition $ M.lookupDefault mempty qi allProcs -- first find the proc by name
+    matchProc = overloadedProcPartition $ HM.lookupDefault mempty qi allProcs -- first find the proc by name
     -- The partition obtained has the form (overloadedProcs,fallbackProcs)
     -- where fallbackProcs are functions with a single unnamed parameter
     overloadedProcPartition procs = foldr select ([],[]) procs
diff --git a/src/PostgREST/Request/DbRequestBuilder.hs b/src/PostgREST/Request/DbRequestBuilder.hs
index ab7fe5d285..8d9fe2e3c5 100644
--- a/src/PostgREST/Request/DbRequestBuilder.hs
+++ b/src/PostgREST/Request/DbRequestBuilder.hs
@@ -21,7 +21,7 @@ module PostgREST.Request.DbRequestBuilder
   , callRequest
   ) where
 
-import qualified Data.HashMap.Strict as M
+import qualified Data.HashMap.Strict as HM
 import qualified Data.Set            as S
 
 import Data.Either.Combinators (mapLeft)
@@ -206,7 +206,7 @@ findRel schema allRels origin target hint =
               -- /users?select=tasks!users_tasks(*) many-to-many between users and tasks
               matchJunction hnt relCardinality -- users_tasks
             )
-      ) $ fromMaybe mempty $ M.lookup (QualifiedIdentifier schema origin, schema) allRels
+      ) $ fromMaybe mempty $ HM.lookup (QualifiedIdentifier schema origin, schema) allRels
 
 -- previousAlias is only used for the case of self joins
 addJoinConditions :: Maybe Alias -> ReadRequest -> Either ApiRequestError ReadRequest
@@ -283,7 +283,7 @@ addRanges ApiRequest{..} rReq =
     _              -> foldr addRangeToNode (Right rReq) =<< ranges
   where
     ranges :: Either ApiRequestError [(EmbedPath, NonnegRange)]
-    ranges = first QueryParamError $ QueryParams.pRequestRange `traverse` M.toList iRange
+    ranges = first QueryParamError $ QueryParams.pRequestRange `traverse` HM.toList iRange
 
     addRangeToNode :: (EmbedPath, NonnegRange) -> Either ApiRequestError ReadRequest -> Either ApiRequestError ReadRequest
     addRangeToNode = updateNode (\r (Node (q,i) f) -> Node (q{range_=r}, i) f)
diff --git a/src/PostgREST/Request/QueryParams.hs b/src/PostgREST/Request/QueryParams.hs
index d03d72a286..4ebb5d9a58 100644
--- a/src/PostgREST/Request/QueryParams.hs
+++ b/src/PostgREST/Request/QueryParams.hs
@@ -13,7 +13,7 @@ module PostgREST.Request.QueryParams
   ) where
 
 import qualified Data.ByteString.Char8         as BS
-import qualified Data.HashMap.Strict           as M
+import qualified Data.HashMap.Strict           as HM
 import qualified Data.List                     as L
 import qualified Data.Set                      as S
 import qualified Data.Text                     as T
@@ -78,7 +78,7 @@ data QueryParams =
     -- ^ Canonical representation of the query params, sorted alphabetically
     , qsParams         :: [(Text, Text)]
     -- ^ Parameters for RPC calls
-    , qsRanges         :: M.HashMap Text (Range Integer)
+    , qsRanges         :: HM.HashMap Text (Range Integer)
     -- ^ Ranges derived from &limit and &offset params
     , qsOrder          :: [(EmbedPath, [OrderTerm])]
     -- ^ &order parameters for each level
@@ -192,8 +192,8 @@ parse qs =
     isEmbedPath = T.isInfixOf "."
     replaceLast x s = T.intercalate "." $ L.init (T.split (=='.') s) <> [x]
 
-    ranges :: M.HashMap Text (Range Integer)
-    ranges = M.unionWith f limitParams offsetParams
+    ranges :: HM.HashMap Text (Range Integer)
+    ranges = HM.unionWith f limitParams offsetParams
       where
         f rl ro = Range (BoundaryBelow o) (BoundaryAbove $ o + l - 1)
           where
@@ -201,10 +201,10 @@ parse qs =
             o = rangeOffset ro
 
         limitParams =
-          M.fromList [(k, restrictRange (readMaybe v) allRange) | (k,v) <- limits]
+          HM.fromList [(k, restrictRange (readMaybe v) allRange) | (k,v) <- limits]
 
         offsetParams =
-          M.fromList [(k, maybe allRange rangeGeq (readMaybe v)) | (k,v) <- offsets]
+          HM.fromList [(k, maybe allRange rangeGeq (readMaybe v)) | (k,v) <- offsets]
 
 operator :: Text -> Maybe SimpleOperator
 operator = \case
diff --git a/stack.yaml b/stack.yaml
index 4cf15d5b75..6f27a3c917 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -11,9 +11,23 @@ nix:
 
 extra-deps:
   - hasql-dynamic-statements-0.3.1@sha256:c3a2c89c4a8b3711368dbd33f0ccfe46a493faa7efc2c85d3e354c56a01dfc48,2673
-  - hasql-implicits-0.1.0.2@sha256:5d54e09cb779a209681b139fb3cc726bae75134557932156340cc0a56dd834a8,1361
+  - hasql-implicits-0.1.0.3@sha256:0015b563ca0e34242f34c5ab518648a02f01b577a469d2d24caced301e7aa33f,1361
   - protolude-0.3.1@sha256:1cc9e5a5c26c33a43c52b554443dd9779fef13974eaa0beec7ca6d2551b400da,2647
   - ptr-0.16.8.1@sha256:525219ec5f5da5c699725f7efcef91b00a7d44120fc019878b85c09440bf51d6,2686
   - wai-extra-3.1.8@sha256:bf3dbe8f4c707b502b2a88262ed71c807220651597b76b56983f864af6197890,7280
-  - wai-logger-2.3.7@sha256:19a0dc5122e22d274776d80786fb9501956f5e75b8f82464bbdad5604d154d82,1671
+  - wai-logger-2.4.0@sha256:630b3d573dce5c6a84dfb372d69f8d15f9dbb52d6a04df43e57a44f0ca0eab0a,1671
   - warp-3.3.19@sha256:c6a47029537d42844386170d732cdfe6d85b2f4279bbaefdd9b50caff6faeebb,10910
+  - aeson-2.0.3.0@sha256:130bda8e10dc6dd159b79b306abb10025d7f8b5d9cbc2f7d6d7e6768a0272058,5845
+  - OneTuple-0.3.1@sha256:a848c096c9d29e82ffdd30a9998aa2931cbccb3a1bc137539d80f6174d31603e,2262
+  - attoparsec-0.14.4@sha256:79584bdada8b730cb5138fca8c35c76fbef75fc1d1e01e6b1d815a5ee9843191,5810
+  - indexed-traversable-0.1.2@sha256:d66228887242f93ccb4fc7101a1e25a6560c8e4708f6e9ee1d3dd21901756c65,2519
+  - primitive-0.7.4.0@sha256:89b88a3e08493b7727fa4089b0692bfbdf7e1e666ef54635f458644eb8358764,2857
+  - semialign-1.2.0.1@sha256:0e179b4d3a8eff79001d374d6c91917c6221696b9620f0a4d86852fc6a9b9501,2836
+  - text-short-0.1.5@sha256:962c6228555debdc46f758d0317dea16e5240d01419b42966674b08a5c3d8fa6,3498
+  - time-compat-1.9.6.1@sha256:42d8f2e08e965e1718917d54ad69e1d06bd4b87d66c41dc7410f59313dba4ed1,5033
+  - base-orphans-0.8.6@sha256:eb6758d0160d607e0c45dbd6b196f515b9a589fd4f6d2f926929dd5d56282d37,3175
+  - hashable-1.3.5.0@sha256:3a2beeafb220f9de706568a7e4a5b3c762cc4c9f25c94d7ef795b8c2d6a691d7,4240
+  - swagger2-2.8@sha256:8166e453462ac6a903e761f27fa25f34074aa20f936bf311e3205e441f3f6b2d,4446
+  - postgresql-binary-0.12.4.2@sha256:c0435803744923d022b01a0a518a680cc2bbb0272893adf6a86b84f0a0ef6455,5690
+  - jose-0.9@sha256:0a312116d10cbddc915b77dbf82958307702e8716f3366bf7d166776498857e2,3251
+  - base64-bytestring-1.2.1.0@sha256:50ec0e229255d4c45cbdd568da011311b8887f304b931564886016f4984334d8,2396
diff --git a/stack.yaml.lock b/stack.yaml.lock
index 540508c290..2fd7a60392 100644
--- a/stack.yaml.lock
+++ b/stack.yaml.lock
@@ -5,57 +5,155 @@
 
 packages:
 - completed:
+    hackage: hasql-dynamic-statements-0.3.1@sha256:c3a2c89c4a8b3711368dbd33f0ccfe46a493faa7efc2c85d3e354c56a01dfc48,2673
     pantry-tree:
-      sha256: b1b9a6a26ec765e5fe29f9a670a5c9ec7067ea00dee8491f0819284ff0201b6f
       size: 641
-    hackage: hasql-dynamic-statements-0.3.1@sha256:c3a2c89c4a8b3711368dbd33f0ccfe46a493faa7efc2c85d3e354c56a01dfc48,2673
+      sha256: b1b9a6a26ec765e5fe29f9a670a5c9ec7067ea00dee8491f0819284ff0201b6f
   original:
     hackage: hasql-dynamic-statements-0.3.1@sha256:c3a2c89c4a8b3711368dbd33f0ccfe46a493faa7efc2c85d3e354c56a01dfc48,2673
 - completed:
+    hackage: hasql-implicits-0.1.0.3@sha256:0015b563ca0e34242f34c5ab518648a02f01b577a469d2d24caced301e7aa33f,1361
     pantry-tree:
-      sha256: 2f00d1467d0e226b966c2cd7bac433c8948e2f7bbdf8a44936029f66fc20b5f3
-      size: 310
-    hackage: hasql-implicits-0.1.0.2@sha256:5d54e09cb779a209681b139fb3cc726bae75134557932156340cc0a56dd834a8,1361
+      size: 264
+      sha256: da00659415431d41abb76cd7dbba2c283922432f67f25c9d7ebf21d72402c22f
   original:
-    hackage: hasql-implicits-0.1.0.2@sha256:5d54e09cb779a209681b139fb3cc726bae75134557932156340cc0a56dd834a8,1361
+    hackage: hasql-implicits-0.1.0.3@sha256:0015b563ca0e34242f34c5ab518648a02f01b577a469d2d24caced301e7aa33f,1361
 - completed:
+    hackage: protolude-0.3.1@sha256:1cc9e5a5c26c33a43c52b554443dd9779fef13974eaa0beec7ca6d2551b400da,2647
     pantry-tree:
-      sha256: 6452a6ca8d395f7d810139779bb0fd16fc1dbb00f1862630bc08ef5a100430f9
       size: 1645
-    hackage: protolude-0.3.1@sha256:1cc9e5a5c26c33a43c52b554443dd9779fef13974eaa0beec7ca6d2551b400da,2647
+      sha256: 6452a6ca8d395f7d810139779bb0fd16fc1dbb00f1862630bc08ef5a100430f9
   original:
     hackage: protolude-0.3.1@sha256:1cc9e5a5c26c33a43c52b554443dd9779fef13974eaa0beec7ca6d2551b400da,2647
 - completed:
+    hackage: ptr-0.16.8.1@sha256:525219ec5f5da5c699725f7efcef91b00a7d44120fc019878b85c09440bf51d6,2686
     pantry-tree:
-      sha256: d2b8440a738719ef8430ec38fe33b129e3940e4ccf2c016a727a1110a43656bb
       size: 1089
-    hackage: ptr-0.16.8.1@sha256:525219ec5f5da5c699725f7efcef91b00a7d44120fc019878b85c09440bf51d6,2686
+      sha256: d2b8440a738719ef8430ec38fe33b129e3940e4ccf2c016a727a1110a43656bb
   original:
     hackage: ptr-0.16.8.1@sha256:525219ec5f5da5c699725f7efcef91b00a7d44120fc019878b85c09440bf51d6,2686
 - completed:
+    hackage: wai-extra-3.1.8@sha256:bf3dbe8f4c707b502b2a88262ed71c807220651597b76b56983f864af6197890,7280
     pantry-tree:
-      sha256: a544ea95288d188e893322a8e6d68f2b1f844f772dbea1f26e5c0c1a74694f56
       size: 4053
-    hackage: wai-extra-3.1.8@sha256:bf3dbe8f4c707b502b2a88262ed71c807220651597b76b56983f864af6197890,7280
+      sha256: a544ea95288d188e893322a8e6d68f2b1f844f772dbea1f26e5c0c1a74694f56
   original:
     hackage: wai-extra-3.1.8@sha256:bf3dbe8f4c707b502b2a88262ed71c807220651597b76b56983f864af6197890,7280
 - completed:
+    hackage: wai-logger-2.4.0@sha256:630b3d573dce5c6a84dfb372d69f8d15f9dbb52d6a04df43e57a44f0ca0eab0a,1671
     pantry-tree:
-      sha256: 52b5abf5c4c09bcfbc06e01f761a75c32cbd3e6ba23c8843981933fcc31ed53c
       size: 474
-    hackage: wai-logger-2.3.7@sha256:19a0dc5122e22d274776d80786fb9501956f5e75b8f82464bbdad5604d154d82,1671
+      sha256: e65ce23ad056ec07ff620d52b9c36c73a68d422dfca28e12e4c0d234f143389c
   original:
-    hackage: wai-logger-2.3.7@sha256:19a0dc5122e22d274776d80786fb9501956f5e75b8f82464bbdad5604d154d82,1671
+    hackage: wai-logger-2.4.0@sha256:630b3d573dce5c6a84dfb372d69f8d15f9dbb52d6a04df43e57a44f0ca0eab0a,1671
 - completed:
+    hackage: warp-3.3.19@sha256:c6a47029537d42844386170d732cdfe6d85b2f4279bbaefdd9b50caff6faeebb,10910
     pantry-tree:
-      sha256: 99ff839445ba2c9e29a294b45904e3f4575336c7d2b4504ce310d611661c761d
       size: 3973
-    hackage: warp-3.3.19@sha256:c6a47029537d42844386170d732cdfe6d85b2f4279bbaefdd9b50caff6faeebb,10910
+      sha256: 99ff839445ba2c9e29a294b45904e3f4575336c7d2b4504ce310d611661c761d
   original:
     hackage: warp-3.3.19@sha256:c6a47029537d42844386170d732cdfe6d85b2f4279bbaefdd9b50caff6faeebb,10910
+- completed:
+    hackage: aeson-2.0.3.0@sha256:130bda8e10dc6dd159b79b306abb10025d7f8b5d9cbc2f7d6d7e6768a0272058,5845
+    pantry-tree:
+      size: 38191
+      sha256: bccfc5a7259a27aad7e4193f367c3d7d67799f42632fdcb90241c1e9fbb0cf40
+  original:
+    hackage: aeson-2.0.3.0@sha256:130bda8e10dc6dd159b79b306abb10025d7f8b5d9cbc2f7d6d7e6768a0272058,5845
+- completed:
+    hackage: OneTuple-0.3.1@sha256:a848c096c9d29e82ffdd30a9998aa2931cbccb3a1bc137539d80f6174d31603e,2262
+    pantry-tree:
+      size: 506
+      sha256: a685b08622f1fe0641e4f228a290878a1db4f7ef3eb63d00b10e8632097d1e6f
+  original:
+    hackage: OneTuple-0.3.1@sha256:a848c096c9d29e82ffdd30a9998aa2931cbccb3a1bc137539d80f6174d31603e,2262
+- completed:
+    hackage: attoparsec-0.14.4@sha256:79584bdada8b730cb5138fca8c35c76fbef75fc1d1e01e6b1d815a5ee9843191,5810
+    pantry-tree:
+      size: 5039
+      sha256: 5b8e087f73d334019252606b1f64b986cef61946a085ccb77c6bc4d038691c48
+  original:
+    hackage: attoparsec-0.14.4@sha256:79584bdada8b730cb5138fca8c35c76fbef75fc1d1e01e6b1d815a5ee9843191,5810
+- completed:
+    hackage: indexed-traversable-0.1.2@sha256:d66228887242f93ccb4fc7101a1e25a6560c8e4708f6e9ee1d3dd21901756c65,2519
+    pantry-tree:
+      size: 495
+      sha256: 7edfd8672d45016089df7227d9f6452117632a7236d4e71b24a2a1041cab4701
+  original:
+    hackage: indexed-traversable-0.1.2@sha256:d66228887242f93ccb4fc7101a1e25a6560c8e4708f6e9ee1d3dd21901756c65,2519
+- completed:
+    hackage: primitive-0.7.4.0@sha256:89b88a3e08493b7727fa4089b0692bfbdf7e1e666ef54635f458644eb8358764,2857
+    pantry-tree:
+      size: 1655
+      sha256: 71a850c658b70e869da19f61615d87d9d6ecec597f0e3d4b498da56559114829
+  original:
+    hackage: primitive-0.7.4.0@sha256:89b88a3e08493b7727fa4089b0692bfbdf7e1e666ef54635f458644eb8358764,2857
+- completed:
+    hackage: semialign-1.2.0.1@sha256:0e179b4d3a8eff79001d374d6c91917c6221696b9620f0a4d86852fc6a9b9501,2836
+    pantry-tree:
+      size: 537
+      sha256: 635bbbb517f0c063a4bc2e9e6efdb0e598b9d9fd467f52df81ab3a4af1fd923b
+  original:
+    hackage: semialign-1.2.0.1@sha256:0e179b4d3a8eff79001d374d6c91917c6221696b9620f0a4d86852fc6a9b9501,2836
+- completed:
+    hackage: text-short-0.1.5@sha256:962c6228555debdc46f758d0317dea16e5240d01419b42966674b08a5c3d8fa6,3498
+    pantry-tree:
+      size: 727
+      sha256: 1fc6561c4acb94a41e58cd8f8c7cce161c18c5629dac63a54a9c62f9c778c52b
+  original:
+    hackage: text-short-0.1.5@sha256:962c6228555debdc46f758d0317dea16e5240d01419b42966674b08a5c3d8fa6,3498
+- completed:
+    hackage: time-compat-1.9.6.1@sha256:42d8f2e08e965e1718917d54ad69e1d06bd4b87d66c41dc7410f59313dba4ed1,5033
+    pantry-tree:
+      size: 4113
+      sha256: b262c5ae8d72d2073d12e1de1863abd234fad8c138df28f32bb51bc232ced608
+  original:
+    hackage: time-compat-1.9.6.1@sha256:42d8f2e08e965e1718917d54ad69e1d06bd4b87d66c41dc7410f59313dba4ed1,5033
+- completed:
+    hackage: base-orphans-0.8.6@sha256:eb6758d0160d607e0c45dbd6b196f515b9a589fd4f6d2f926929dd5d56282d37,3175
+    pantry-tree:
+      size: 1272
+      sha256: f889d6903383305688e6e703982bfdc985649b7d4538429e44f98f99d8f73c07
+  original:
+    hackage: base-orphans-0.8.6@sha256:eb6758d0160d607e0c45dbd6b196f515b9a589fd4f6d2f926929dd5d56282d37,3175
+- completed:
+    hackage: hashable-1.3.5.0@sha256:3a2beeafb220f9de706568a7e4a5b3c762cc4c9f25c94d7ef795b8c2d6a691d7,4240
+    pantry-tree:
+      size: 1248
+      sha256: 4df2f6b536a0fcc5f7d562cb29e373f27dc4a2747452ac5cc74c1599cab22fc5
+  original:
+    hackage: hashable-1.3.5.0@sha256:3a2beeafb220f9de706568a7e4a5b3c762cc4c9f25c94d7ef795b8c2d6a691d7,4240
+- completed:
+    hackage: swagger2-2.8@sha256:8166e453462ac6a903e761f27fa25f34074aa20f936bf311e3205e441f3f6b2d,4446
+    pantry-tree:
+      size: 2192
+      sha256: 1c3f5503292e0323a2fd925250ac534e0d8d32c1c3fcae3e0c61c35e12a78e83
+  original:
+    hackage: swagger2-2.8@sha256:8166e453462ac6a903e761f27fa25f34074aa20f936bf311e3205e441f3f6b2d,4446
+- completed:
+    hackage: postgresql-binary-0.12.4.2@sha256:c0435803744923d022b01a0a518a680cc2bbb0272893adf6a86b84f0a0ef6455,5690
+    pantry-tree:
+      size: 1665
+      sha256: db2520640f426cdec35a1d4f5072cf6cf50a971cc2c5c5972104605f4307b831
+  original:
+    hackage: postgresql-binary-0.12.4.2@sha256:c0435803744923d022b01a0a518a680cc2bbb0272893adf6a86b84f0a0ef6455,5690
+- completed:
+    hackage: jose-0.9@sha256:0a312116d10cbddc915b77dbf82958307702e8716f3366bf7d166776498857e2,3251
+    pantry-tree:
+      size: 2105
+      sha256: b787b8fa8a0ffe381a55a8b66f088d80ed7be0bc5acaf2c54cee78c4ab5fee1b
+  original:
+    hackage: jose-0.9@sha256:0a312116d10cbddc915b77dbf82958307702e8716f3366bf7d166776498857e2,3251
+- completed:
+    hackage: base64-bytestring-1.2.1.0@sha256:50ec0e229255d4c45cbdd568da011311b8887f304b931564886016f4984334d8,2396
+    pantry-tree:
+      size: 850
+      sha256: 1154783dd163be45502456716ca44c4244d0aa6e7cf1aa4e7763efb3485a509c
+  original:
+    hackage: base64-bytestring-1.2.1.0@sha256:50ec0e229255d4c45cbdd568da011311b8887f304b931564886016f4984334d8,2396
 snapshots:
 - completed:
-    sha256: 87842ecbaa8ca9cee59a7e6be52369dbed82ed075cb4e0d152614a627e8fd488
     size: 586069
     url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/18/14.yaml
+    sha256: 87842ecbaa8ca9cee59a7e6be52369dbed82ed075cb4e0d152614a627e8fd488
   original: lts-18.14
diff --git a/test/io/test_io.py b/test/io/test_io.py
index ef31c036f4..bf4f4cb915 100644
--- a/test/io/test_io.py
+++ b/test/io/test_io.py
@@ -922,7 +922,7 @@ def test_log_level(level, has_output, defaultenv):
         assert response.status_code == 200
         if has_output[0]:
             assert re.match(
-                r'unknownSocket - postgrest_test_anonymous \[.+\] "GET / HTTP/1.1" 200 - "" "python-requests/.+"',
+                r'- - postgrest_test_anonymous \[.+\] "GET / HTTP/1.1" 200 - "" "python-requests/.+"',
                 postgrest.process.stdout.readline().decode(),
             )
 
@@ -930,7 +930,7 @@ def test_log_level(level, has_output, defaultenv):
         assert response.status_code == 404
         if has_output[1]:
             assert re.match(
-                r'unknownSocket - postgrest_test_anonymous \[.+\] "GET /unknown HTTP/1.1" 404 - "" "python-requests/.+"',
+                r'- - postgrest_test_anonymous \[.+\] "GET /unknown HTTP/1.1" 404 - "" "python-requests/.+"',
                 postgrest.process.stdout.readline().decode(),
             )
 
@@ -938,7 +938,7 @@ def test_log_level(level, has_output, defaultenv):
         assert response.status_code == 500
         if has_output[2]:
             assert re.match(
-                r'unknownSocket - - \[.+\] "GET / HTTP/1.1" 500 - "" "python-requests/.+"',
+                r'- - - \[.+\] "GET / HTTP/1.1" 500 - "" "python-requests/.+"',
                 postgrest.process.stdout.readline().decode(),
             )