4 files changed, 24 insertions, 14 deletions
diff --git a/src/CabalHelper/Compiletime/Compile.hs b/src/CabalHelper/Compiletime/Compile.hs
index e468c1b..e5d7dcd 100644
--- a/src/CabalHelper/Compiletime/Compile.hs
+++ b/src/CabalHelper/Compiletime/Compile.hs
@@ -112,7 +112,7 @@ compileHelper'
     => CompHelperEnv' UnpackedCabalVersion
     -> IO (Either ExitCode FilePath)
 compileHelper' CompHelperEnv {..} = do
-  ghcVer <- ghcVersion
+  ghcVer <- GhcVersion <$> getGhcVersion
   Just (prepare, comp) <- case cheCabalVer of
     cabalVer@CabalHEAD {} -> runMaybeT $ msum  $ map (\f -> f ghcVer cabalVer)
       [ compileWithCabalV2GhcEnv'
@@ -217,7 +217,7 @@ compileHelper' CompHelperEnv {..} = do
    compileWithCabalV2GhcEnv' :: Env => GhcVersion -> UnpackedCabalVersion -> MaybeT IO (IO (), Compile)
    compileWithCabalV2GhcEnv' ghcVer cabalVer = do
        _ <- maybe mzero pure cheDistV2 -- bail if this isn't a v2-build project
-       CabalInstallVersion instVer <- liftIO cabalInstallVersion
+       instVer <- liftIO getCabalInstallVersion
        guard $ instVer >= (Version [2,4,1,0] [])
        --  ^ didn't test with older versions
        guard $ ghcVer  >= (GhcVersion (Version [8,0] []))
diff --git a/src/CabalHelper/Compiletime/Program/CabalInstall.hs b/src/CabalHelper/Compiletime/Program/CabalInstall.hs
index 40f0561..36d6c63 100644
--- a/src/CabalHelper/Compiletime/Program/CabalInstall.hs
+++ b/src/CabalHelper/Compiletime/Program/CabalInstall.hs
@@ -57,11 +57,16 @@ newtype CabalInstallVersion = CabalInstallVersion { cabalInstallVer :: Version }
 
 data HEAD = HEAD deriving (Eq, Show)
 
-cabalInstallVersion :: (Verbose, Progs) => IO CabalInstallVersion
-cabalInstallVersion = do
-  CabalInstallVersion . parseVer . trim
+getCabalInstallVersion :: (Verbose, Progs) => IO Version
+getCabalInstallVersion = do
+  parseVer . trim
     <$> readProcess' (cabalProgram ?progs) ["--numeric-version"] ""
 
+getCabalInstallBuiltinCabalVersion :: (Verbose, Progs) => IO Version
+getCabalInstallBuiltinCabalVersion =
+    parseVer . trim <$> readProcess' (cabalProgram ?progs)
+        ["act-as-setup", "--", "--numeric-version"] ""
+
 installCabalLibV1 :: Env => GhcVersion -> UnpackedCabalVersion -> IO PackageDbDir
 installCabalLibV1 ghcVer cabalVer = do
   withSystemTempDirectory "cabal-helper.install-cabal-tmp" $ \tmpdir -> do
@@ -117,7 +122,7 @@ callCabalInstallV1
   ghcVer
   unpackedCabalVer
   = do
-  civ@CabalInstallVersion {..} <- cabalInstallVersion
+  cabalInstallVer <- getCabalInstallVersion
   cabal_opts <- return $ concat
       [
         [ "--package-db=clear"
@@ -140,7 +145,7 @@ callCabalInstallV1
 
   callProcessStderr (Just "/") [] (cabalProgram ?progs) cabal_opts
 
-  runSetupHs ghcVer db srcdir unpackedCabalVer civ
+  runSetupHs ghcVer db srcdir unpackedCabalVer $ CabalInstallVersion cabalInstallVer
 
   hPutStrLn stderr "done"
 
@@ -221,7 +226,7 @@ installCabalLibV2 _ghcVer cv (PackageEnvFile env_file) = do
         return $ ("Cabal-"++showVersion cabalVer, "/")
       CabalHEAD (_commitid, CabalSourceDir srcdir) -> do
         return (".", srcdir)
-    CabalInstallVersion {..} <- cabalInstallVersion
+    cabalInstallVer <- getCabalInstallVersion
     cabal_opts <- return $ concat
         [ if cabalInstallVer >= Version [1,20] []
              then ["--no-require-sandbox"]
diff --git a/src/CabalHelper/Compiletime/Program/GHC.hs b/src/CabalHelper/Compiletime/Program/GHC.hs
index 9ab0b33..7723a1f 100644
--- a/src/CabalHelper/Compiletime/Program/GHC.hs
+++ b/src/CabalHelper/Compiletime/Program/GHC.hs
@@ -60,16 +60,16 @@ newtype GhcVersion = GhcVersion { unGhcVersion :: Version }
 showGhcVersion :: GhcVersion -> String
 showGhcVersion (GhcVersion v) = showVersion v
 
-ghcVersion :: (Verbose, Progs) => IO GhcVersion
-ghcVersion = GhcVersion .
+getGhcVersion :: (Verbose, Progs) => IO Version
+getGhcVersion =
   parseVer . trim <$> readProcess' (ghcProgram ?progs) ["--numeric-version"] ""
 
 ghcLibdir :: (Verbose, Progs) => IO FilePath
 ghcLibdir = do
   trim <$> readProcess' (ghcProgram ?progs) ["--print-libdir"] ""
 
-ghcPkgVersion :: (Verbose, Progs) => IO Version
-ghcPkgVersion =
+getGhcPkgVersion :: (Verbose, Progs) => IO Version
+getGhcPkgVersion =
   parseVer . trim . dropWhile (not . isDigit)
     <$> readProcess' (ghcPkgProgram ?progs) ["--version"] ""
 
@@ -85,9 +85,9 @@ createPkgDb cabalVer = do
 getPrivateCabalPkgDb :: (Verbose, Progs) => ResolvedCabalVersion -> IO PackageDbDir
 getPrivateCabalPkgDb cabalVer = do
   appdir <- appCacheDir
-  ghcVer <- ghcVersion
+  ghcVer <- getGhcVersion
   let db_path =
-        appdir </> "ghc-" ++ showGhcVersion ghcVer ++ ".package-dbs"
+        appdir </> "ghc-" ++ showVersion ghcVer ++ ".package-dbs"
                </> "Cabal-" ++ showResolvedCabalVersion cabalVer
   return $ PackageDbDir db_path
 
diff --git a/src/CabalHelper/Compiletime/Program/Stack.hs b/src/CabalHelper/Compiletime/Program/Stack.hs
index dc0b0e5..fe817cb 100644
--- a/src/CabalHelper/Compiletime/Program/Stack.hs
+++ b/src/CabalHelper/Compiletime/Program/Stack.hs
@@ -38,8 +38,13 @@ import Prelude
 
 import CabalHelper.Compiletime.Types
 import CabalHelper.Compiletime.Types.RelativePath
+import CabalHelper.Compiletime.Process
 import CabalHelper.Shared.Common
 
+getStackVersion :: (Verbose, Progs) => IO Version
+getStackVersion =
+  parseVer . trim <$> readProcess' (stackProgram ?progs) [ "--numeric-version" ] ""
+
 getPackage :: QueryEnvI c 'Stack -> CabalFile -> IO (Package 'Stack)
 getPackage qe cabal_file@(CabalFile cabal_file_path) = do
   let pkgdir = takeDirectory cabal_file_path