Modernize Haskell toolchain: PureScript 0.15.16, GHC 9.8.4, latest package set

.github/workflows/ci.yml

@@ -35,7 +35,7 @@ jobs:
           key: ${{ runner.os }}-stack-${{ hashFiles('stack.yaml.lock') }}-${{ hashFiles('trypurescript.cabal') }}
 
       - name: Build server code
-        run: stack --no-terminal -j1 build
+        run: stack --no-terminal build
 
       - name: Build server assets
         if: github.event_name == 'release'
@@ -62,7 +62,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
         with:
-          node-version: "20"
+          node-version: "22"
 
       - name: Build client code
         run: |

CHANGELOG.md

@@ -11,6 +11,12 @@ New features:
 Bugfixes:
 
 Other improvements:
+- Update the PureScript compiler to [0.15.16](https://github.com/purescript/purescript/releases/tag/v0.15.16) and the package set to `psc-0.15.15-20260701` (#320 by @thomashoneyman)
+  - Since 0.15.16 was not published to Hackage, `stack.yaml` now pins the `v0.15.16` release tag on GitHub instead of a Hackage version.
+- Modernize the Haskell toolchain from Stackage `lts-20.9` (GHC 9.2.5) to `lts-23.18` (GHC 9.8.4), matching the upstream `purescript` repository (#320 by @thomashoneyman)
+- Modernize the server for scotty 0.22 and GHC 9.8, build with `-Wall`, prune unused dependencies, and update the cabal file to `cabal-version: 2.4` (#320 by @thomashoneyman)
+- Update the CI client build to Node 22, as Node 20 reached end of life in April 2026 (#320 by @thomashoneyman)
+- Raise the server's RTS heap cap from 3G to 6G to accommodate the larger package set; deploying this requires resizing the try.purescript.org droplet beyond 4GB of RAM (#320 by @thomashoneyman)
 
 ## [v2026-07-03.1](https://github.com/purescript/trypurescript/releases/tag/v2026-07-03.1)
 

client/package.json

@@ -16,7 +16,7 @@
   "devDependencies": {
     "esbuild": "^0.14.43",
     "http-server": "^14.1.0",
-    "purescript": "^0.15.2",
+    "purescript": "^0.15.16",
     "purescript-psa": "^0.8.2",
     "rimraf": "^2.5.4",
     "spago": "^0.20.9"

client/src/Try/SharedConfig.purs

@@ -6,13 +6,13 @@ module Try.SharedConfig where
 import Prelude
 
 pursVersion :: String
-pursVersion = "v0.15.13"
+pursVersion = "v0.15.16"
 
 pursReleaseUrl :: String
 pursReleaseUrl = "https://github.com/purescript/purescript/releases/tag/" <> pursVersion
 
 packageSetVersion :: String
-packageSetVersion = "0.15.13-20231219"
+packageSetVersion = "0.15.15-20260701"
 
 packageSetPackageJsonUrl :: String
 packageSetPackageJsonUrl = "https://github.com/purescript/package-sets/blob/psc-" <> packageSetVersion <> "/packages.json"

client/updateSharedConfigVersions.mjs

@@ -19,15 +19,23 @@ const stagingPackagesDhallPath = path.join("..", "staging", "packages.dhall");
 const stackYamlContent = fs.readFileSync(stackYamlPath, "utf-8");
 const packagesContent = fs.readFileSync(stagingPackagesDhallPath, "utf-8");
 
-const pursVersion = stackYamlContent.split("\n")
-  .reduce((acc, nextLine) => {
-    if (acc.found) return acc;
-    const matchResult = nextLine.match(/ +- purescript-(.+)/);
-    return matchResult
-      ? { found: true, value: matchResult[1] }
-      : acc;
-  }, { found: false })
-  .value;
+// The `purescript` extra-dep is either a Hackage dependency, e.g.
+//   - purescript-0.15.13
+// or a GitHub dependency pinned to a release tag, e.g.
+//   - github: purescript/purescript
+//     commit: v0.15.16
+const pursVersion = (() => {
+  const lines = stackYamlContent.split("\n");
+  for (let i = 0; i < lines.length; i++) {
+    const hackageMatch = lines[i].match(/ +- purescript-(.+)/);
+    if (hackageMatch) return hackageMatch[1];
+    if (/ +- github: purescript\/purescript\s*$/.test(lines[i])) {
+      const commitMatch = (lines[i + 1] ?? "").match(/ +commit: v(.+)/);
+      if (commitMatch) return commitMatch[1];
+    }
+  }
+  return undefined;
+})();
 
 const packageSetVersion = packagesContent
   .match(/https:\/\/github.com\/purescript\/package-sets\/releases\/download\/psc-([^\/]+)\/packages.dhall/)[1];

deploy/start

@@ -4,4 +4,7 @@ set -ex
 set -o noglob
 export XDG_CACHE_HOME="$PWD/.spago-cache"
 spago install
-exec trypurescript +RTS -N2 -A128m -M3G -RTS 8081 $(spago sources)
+# Note: the heap cap below must fit within the droplet's RAM; the package set
+# as of psc-0.15.15-20260701 (641 packages) needs more than the 3G that
+# sufficed for psc-0.15.13-20231219 (459 packages).
+exec trypurescript +RTS -N2 -A128m -M6G -RTS 8081 $(spago sources)

server/Main.hs

@@ -6,26 +6,20 @@
 
 module Main (main) where
 
-import           Control.Monad (unless, foldM)
-import           Control.Monad.Error.Class (throwError)
-import           Control.Monad.IO.Class (liftIO)
-import           Control.Monad.Logger (runLogger')
+import           Control.Monad (foldM)
 import qualified Control.Monad.State as State
 import           Control.Monad.Trans (lift)
 import           Control.Monad.Trans.Except (ExceptT(..), runExceptT)
-import           Control.Monad.Trans.Reader (runReaderT)
 import           Control.Monad.Writer.Strict (runWriterT)
 import qualified Data.Aeson as A
 import           Data.Aeson ((.=))
-import           Data.Bifunctor (first, second, bimap)
+import           Data.Bifunctor (second, bimap)
 import qualified Data.ByteString.Lazy as BL
-import           Data.Default (def)
 import           Data.Function (on)
 import qualified Data.IORef as IORef
 import           Data.List (nubBy)
 import qualified Data.List.NonEmpty as NE
 import qualified Data.Map as M
-import           Data.Set (Set)
 import qualified Data.Set as Set
 import           Data.Text (Text)
 import qualified Data.Text as T
@@ -50,6 +44,7 @@ import           System.Environment (getArgs)
 import           System.Exit (exitFailure)
 import           System.FilePath.Glob (glob)
 import qualified System.IO as IO
+import           Text.Read (readMaybe)
 import           Web.Scotty
 import qualified Web.Scotty as Scotty
 
@@ -162,7 +157,7 @@ server allModuleNames externs initNamesEnv initEnv port = do
 
     post "/compile" $ do
       code <- T.decodeUtf8 . BL.toStrict <$> body
-      response <- lift $ compile code
+      response <- liftIO $ compile code
       Scotty.setHeader "Access-Control-Allow-Origin" "*"
       case response of
         Left err ->
@@ -171,7 +166,7 @@ server allModuleNames externs initNamesEnv initEnv port = do
           Scotty.json $ A.object [ "js" .= comp, "warnings" .= warnings ]
 
     get "/search" $ do
-      query <- param "q"
+      query <- queryParam "q"
       Scotty.setHeader "Access-Control-Allow-Origin" "*"
       Scotty.setHeader "Content-Type" "application/json"
       case tryParseType query of
@@ -191,7 +186,7 @@ server allModuleNames externs initNamesEnv initEnv port = do
                                  ]
 
 getOpts :: Int -> Scotty.Options
-getOpts port = def
+getOpts port = Scotty.defaultOptions
   { settings =
       Warp.setHost "127.0.0.1"
       $ Warp.setPort port
@@ -204,9 +199,9 @@ lookupAllConstructors env = P.everywhereOnTypesM $ \case
     other -> pure other
   where
     lookupConstructor :: P.Environment -> P.ProperName 'P.TypeName -> [P.Qualified (P.ProperName 'P.TypeName)]
-    lookupConstructor env nm =
+    lookupConstructor env' nm =
       [ q
-      | (q@(P.Qualified (N.ByModuleName _) thisNm), _) <- M.toList (P.types env)
+      | (q@(P.Qualified (N.ByModuleName _) thisNm), _) <- M.toList (P.types env')
       , thisNm == nm
       ]
 
@@ -216,15 +211,15 @@ lookupAllConstructors env = P.everywhereOnTypesM $ \case
 replaceTypeVariablesAndDesugar :: (Text -> Int -> P.SourceType) -> P.SourceType -> P.SourceType
 replaceTypeVariablesAndDesugar f ty = State.evalState (P.everywhereOnTypesM go ty) (0, M.empty) where
   go = \case
-    P.ParensInType _ ty -> pure ty
+    P.ParensInType _ inner -> pure inner
     P.TypeVar _ s -> do
-      (next, m) <- State.get
+      (n, m) <- State.get
       case M.lookup s m of
         Nothing -> do
-          let ty = f s next
-          State.put (next + 1, M.insert s ty m)
-          pure ty
-        Just ty -> pure ty
+          let unknown = f s n
+          State.put (n + 1, M.insert s unknown m)
+          pure unknown
+        Just unknown -> pure unknown
     other -> pure other
 
 tryParseType :: Text -> Maybe P.SourceType
@@ -242,16 +237,24 @@ main :: IO ()
 main = do
   -- Stop mangled "Compiling ModuleName" text
   IO.hSetBuffering IO.stderr IO.LineBuffering
-  (portString : inputGlobs) <- getArgs
-  let port = read portString
-  inputFiles <- concat <$> traverse glob inputGlobs
-  e <- runExceptT $ do
-    modules <- ExceptT $ I.loadAllModules inputFiles
-    (exts, env) <- ExceptT . I.runMake . I.make $ map (second CST.pureResult) modules
-    namesEnv <- fmap fst . runWriterT $ foldM P.externsEnv P.primEnv exts
-    let
-      allModuleNames = fmap (P.getModuleName . snd) modules
-    pure (allModuleNames, exts, namesEnv, env)
-  case e of
-    Left err -> print err >> exitFailure
-    Right (allModuleNames, exts, namesEnv, env) -> server allModuleNames exts namesEnv env port
+  args <- getArgs
+  case args of
+    portString : inputGlobs
+      | Just port <- readMaybe portString -> run port inputGlobs
+    _ -> do
+      IO.hPutStrLn IO.stderr "Usage: trypurescript PORT INPUT_GLOB..."
+      exitFailure
+  where
+  run :: Int -> [String] -> IO ()
+  run port inputGlobs = do
+    inputFiles <- concat <$> traverse glob inputGlobs
+    e <- runExceptT $ do
+      modules <- ExceptT $ I.loadAllModules inputFiles
+      (exts, env) <- ExceptT . I.runMake . I.make $ map (second CST.pureResult) modules
+      namesEnv <- fmap fst . runWriterT $ foldM P.externsEnv P.primEnv exts
+      let
+        allModuleNames = fmap (P.getModuleName . snd) modules
+      pure (allModuleNames, exts, namesEnv, env)
+    case e of
+      Left err -> print err >> exitFailure
+      Right (allModuleNames, exts, namesEnv, env) -> server allModuleNames exts namesEnv env port

stack.yaml

@@ -1,16 +1,24 @@
-resolver: lts-20.9
+resolver: lts-23.18
+
 packages:
   - "."
 
 extra-deps:
-  - purescript-0.15.13
+  # purescript 0.15.16 was not uploaded to Hackage, so we pin its release tag
+  # on GitHub instead. Note that `client/updateSharedConfigVersions.mjs`
+  # derives the compiler version from the `commit` value below.
+  - github: purescript/purescript
+    commit: v0.15.16
+
+  # The extra dependencies below mirror the `extra-deps` listed in the
+  # purescript repository's stack.yaml at the version pinned above.
   - language-javascript-0.7.0.0
-  - process-1.6.13.1
-  # The Cabal library is not in Stackage
-  - Cabal-3.6.3.0
-  # Protolude is not yet in resolver snapshot
-  - protolude-0.3.1
+  - bower-json-1.1.0.0
+  - these-1.2.1
+  - aeson-better-errors-0.9.1.3
+  - github: purescript/cheapskate
+    commit: 633c69024e061ad956f1aecfc137fb99a7a7a20b
 
 flags:
-  these:
-    assoc: false
+  aeson-pretty:
+    lib-only: true

stack.yaml.lock

@@ -1,16 +1,20 @@
 # This file was autogenerated by Stack.
 # You should not edit this file by hand.
 # For more information, please see the documentation at:
-#   https://docs.haskellstack.org/en/stable/lock_files
+#   https://docs.haskellstack.org/en/stable/topics/lock_files
 
 packages:
 - completed:
-    hackage: purescript-0.15.13@sha256:ed7e4d3561ff6cbc7f950af2450a51f71648c47fece8b9a2b5100f0157a47615,21378
+    name: purescript
     pantry-tree:
-      sha256: f91a02104c2bb596613dca4cf460e8e218488791b8d2f1d0641cd0e73c9eb072
-      size: 159072
+      sha256: c16a7cd421dd7b39a4cd19e062bc5243e4573ce29531e8c6734c1e50c107be07
+      size: 149027
+    sha256: 36abaef46aa3cd0316d924c872987aa186d95654d05aa66060948ab47b161f18
+    size: 891651
+    url: https://github.com/purescript/purescript/archive/v0.15.16.tar.gz
+    version: 0.15.16
   original:
-    hackage: purescript-0.15.13
+    url: https://github.com/purescript/purescript/archive/v0.15.16.tar.gz
 - completed:
     hackage: language-javascript-0.7.0.0@sha256:3eab0262b8ac5621936a4beab6a0f97d0e00a63455a8b0e3ac1547b4088dae7d,3898
     pantry-tree:
@@ -19,29 +23,40 @@ packages:
   original:
     hackage: language-javascript-0.7.0.0
 - completed:
-    hackage: process-1.6.13.1@sha256:c8bb8b7c993ff72d771381b3b56852dd154bce51880a24789c11f57b0688d353,2963
+    hackage: bower-json-1.1.0.0@sha256:a136aaca67bf0d15c336f5864f7e9d40ebe046ca2cb4b25bc4895617ea35f9f6,1864
     pantry-tree:
-      sha256: 58117b15fa330c79b3bca6b29c65f815e45840f79cc0915d3434f25e54ac8fa5
-      size: 1543
+      sha256: 3acd48e7012f246ad44c7c17cd6340362b1dc448c1d93156280814e76d9e0589
+      size: 419
   original:
-    hackage: process-1.6.13.1
+    hackage: bower-json-1.1.0.0
 - completed:
-    hackage: Cabal-3.6.3.0@sha256:ff97c442b0c679c1c9876acd15f73ac4f602b973c45bde42b43ec28265ee48f4,12459
+    hackage: these-1.2.1@sha256:35c57aede96c15ea1fed559ac287b1168eb2b2869d79e62ed8c845780b7ea136,2294
     pantry-tree:
-      sha256: b250a53bdb56844f047a2927833bb565b936a289abfa85dfc2a63148d776368a
-      size: 19757
+      sha256: dc6366ac715dfdf5338a615f71b9ed0542c403a6afcbedcddbc879e947aea6b3
+      size: 351
   original:
-    hackage: Cabal-3.6.3.0
+    hackage: these-1.2.1
 - completed:
-    hackage: protolude-0.3.1@sha256:1cc9e5a5c26c33a43c52b554443dd9779fef13974eaa0beec7ca6d2551b400da,2647
+    hackage: aeson-better-errors-0.9.1.3@sha256:1bfdda3982368cafc7317b9f0c1f7267a6b0bbac9515ae1fad37f2b19178f567,2071
     pantry-tree:
-      sha256: 6452a6ca8d395f7d810139779bb0fd16fc1dbb00f1862630bc08ef5a100430f9
-      size: 1645
+      sha256: 1c14247866dfb8052506c179e4725b8a7ce1472a4fb227d61576d862d9494551
+      size: 492
   original:
-    hackage: protolude-0.3.1
+    hackage: aeson-better-errors-0.9.1.3
+- completed:
+    name: cheapskate
+    pantry-tree:
+      sha256: b130a35ad29a61ac64c2d29bb09309ddf07b139342c67ef01ccc59ad4167d529
+      size: 12069
+    sha256: 2b495e2b6d571c33b91ebb76c1b7fe9c9b56ff90ca0804106a3260f2bbdc9a9a
+    size: 62489
+    url: https://github.com/purescript/cheapskate/archive/633c69024e061ad956f1aecfc137fb99a7a7a20b.tar.gz
+    version: 0.1.1.2
+  original:
+    url: https://github.com/purescript/cheapskate/archive/633c69024e061ad956f1aecfc137fb99a7a7a20b.tar.gz
 snapshots:
 - completed:
-    sha256: c11fcbeb1aa12761044755b1109d16952ede2cb6147ebde777dd5cb38f784501
-    size: 649333
-    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/20/9.yaml
-  original: lts-20.9
+    sha256: d133abe75e408a407cce3f032c96ac1bbadf474a93b5156ebf4135b53382d56b
+    size: 683827
+    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/23/18.yaml
+  original: lts-23.18

staging/packages.dhall

@@ -1,6 +1,6 @@
 let upstream =
-      https://github.com/purescript/package-sets/releases/download/psc-0.15.13-20231219/packages.dhall
-        sha256:35b9271b0a49390a9681995c609dbf7357402a1f209e0549d840bca295abe57b
+      https://github.com/purescript/package-sets/releases/download/psc-0.15.15-20260701/packages.dhall
+        sha256:bb62858371c55d439baa6bcf463ab70cfe8753d5e1f0520b0955468c018213d6
 
 in  upstream
-  with metadata.version = "v0.15.13"
+  with metadata.version = "v0.15.16"