diff --git a/Changelog.md b/Changelog.md
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,3 +1,7 @@
+20250316 haskell-debug-adapter-0.0.42.0
+  * [PR] Use hie-bios to generalize build command #37
+
+
 20250209 haskell-debug-adapter-0.0.41.0
   * [MODIFY] Improved debug console output.
 
diff --git a/haskell-debug-adapter.cabal b/haskell-debug-adapter.cabal
--- a/haskell-debug-adapter.cabal
+++ b/haskell-debug-adapter.cabal
@@ -1,13 +1,11 @@
 cabal-version: 1.12
 
--- This file has been generated from package.yaml by hpack version 0.35.2.
+-- This file has been generated from package.yaml by hpack version 0.37.0.
 --
 -- see: https://github.com/sol/hpack
---
--- hash: 31df6f8a3983d139dd38dfb23e6a70668fe0e158220e5b7a993db5050d161c30
 
 name:           haskell-debug-adapter
-version:        0.0.41.0
+version:        0.0.42.0
 synopsis:       Haskell Debug Adapter.
 description:    Please see README.md
 category:       Development
@@ -55,7 +53,7 @@
       Haskell.Debug.Adapter.TH.Utility
       Haskell.Debug.Adapter.Type
       Haskell.Debug.Adapter.Utility
-      -- Haskell.Debug.Adapter.Watch
+      Haskell.Debug.Adapter.Watch
       Paths_haskell_debug_adapter
   hs-source-dirs:
       src
@@ -111,9 +109,10 @@
     , data-default
     , directory
     , filepath
-    -- , fsnotify
+    , fsnotify
     , ghci-dap >=0.0.23.0
     , haskell-dap >=0.0.16.0
+    , hie-bios >=0.13
     , hslogger
     , lens
     , mtl
@@ -185,10 +184,11 @@
     , data-default
     , directory
     , filepath
-    -- , fsnotify
+    , fsnotify
     , ghci-dap >=0.0.23.0
     , haskell-dap >=0.0.16.0
     , haskell-debug-adapter
+    , hie-bios >=0.13
     , hslogger
     , lens
     , mtl
@@ -263,10 +263,11 @@
     , data-default
     , directory
     , filepath
-    -- , fsnotify
+    , fsnotify
     , ghci-dap >=0.0.23.0
     , haskell-dap >=0.0.16.0
     , haskell-debug-adapter
+    , hie-bios >=0.13
     , hslogger
     , hspec
     , lens
diff --git a/src/Haskell/Debug/Adapter/State/Init/Launch.hs b/src/Haskell/Debug/Adapter/State/Init/Launch.hs
--- a/src/Haskell/Debug/Adapter/State/Init/Launch.hs
+++ b/src/Haskell/Debug/Adapter/State/Init/Launch.hs
@@ -1,8 +1,11 @@
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 
 module Haskell.Debug.Adapter.State.Init.Launch where
 
+import Control.Monad
 import Control.Monad.IO.Class
 import Control.Monad.Except
 import Control.Monad.State
@@ -14,6 +17,7 @@
 import qualified Data.ByteString.Lazy as LB
 import qualified Data.List as L
 import qualified Data.Version as V
+import qualified System.Directory as D
 
 import qualified Haskell.DAP as DAP
 import qualified Haskell.Debug.Adapter.Utility as U
@@ -23,6 +27,9 @@
 import qualified Haskell.Debug.Adapter.Logger as L
 import qualified Haskell.Debug.Adapter.GHCi as P
 
+import qualified HIE.Bios as HIE
+import qualified HIE.Bios.Types as HIE
+import qualified HIE.Bios.Environment as HIE
 
 -- |
 --   Any errors should be critical. don't catch anything here.
@@ -48,11 +55,11 @@
 
   -- must start here. can not start in the entry of GHCiRun State.
   -- because there is a transition from DebugRun to GHCiRun.
-  startGHCi req
+  flags <- startGHCi req
   setPrompt
   launchCmd req
   setMainArgs
-  loadStarupFile
+  loadStarupFile flags
 
   -- dont send launch response here.
   -- it must send after configuration done response.
@@ -127,39 +134,81 @@
   liftIO $ L.setUpLogger (DAP.logFileLaunchRequestArguments args) logPR
 
 
--- |
---
-startGHCi :: DAP.LaunchRequest -> AppContext ()
+-- | Starts GHCi and returns the list of arguments it passed to invoke it.
+startGHCi :: DAP.LaunchRequest -> AppContext [String]
 startGHCi req = do
   let args = DAP.argumentsLaunchRequest req
       initPmpt = maybe _GHCI_PROMPT id (DAP.ghciInitialPromptLaunchRequestArguments args)
       envs = DAP.ghciEnvLaunchRequestArguments args
-      cmdStr = DAP.ghciCmdLaunchRequestArguments args
-      cmdList = filter (not.null) $ U.split " " cmdStr
-      cmd  = head cmdList
 
-  U.debugEV _LOG_APP $ show cmdList
+      -- Ignore ghciCmd LaunchRequestArguments
+      -- Instead, use `hie-bios` to do the Right Thing across projects without complicated user input.
+      -- Eventually, get rid of this option from haskell-dap.
+      cmdStr = DAP.ghciCmdLaunchRequestArguments args
+      (cmd:cmdOpts) = filter (not.null) $ U.split " " cmdStr
 
-  opts <- addWithGHC (tail cmdList)
+      startup_file = DAP.startupLaunchRequestArguments args
 
   appStores <- get
   cwd <- U.liftIOE $ readMVar $ appStores^.workspaceAppStores
 
+  -- Use hie-bios when Cmd is exactly "ghci-dap"
+  flags <- if cmdStr /= "ghci-dap" then addWithGHC cmdOpts else do
+    isExist <- U.liftIOE $ D.doesFileExist startup_file
+    when (False == isExist) $ do
+      U.sendErrorEventLF $ "file not found. [" ++ startup_file ++ "]"
+      -- throwError $ "file not found. [" ++ startup_file ++ "]"
+
+    explicitCradle <- U.liftIOE $ HIE.findCradle startup_file
+    cradle <- U.liftIOE $ maybe (HIE.loadImplicitCradle mempty startup_file)
+                                (HIE.loadCradle mempty) explicitCradle
+
+    libdir <- U.liftIOE (HIE.getRuntimeGhcLibDir cradle) >>= unwrapCradleResult "Failed to get runtime GHC libdir"
+
+    -- getCompilerOptions depends on CWD being the proper root dir.
+    let compilerOpts = D.withCurrentDirectory cwd $
+#if MIN_VERSION_hie_bios(0,14,0)
+                          HIE.getCompilerOptions startup_file HIE.LoadFile cradle
+#else
+                          HIE.getCompilerOptions startup_file [] cradle
+#endif
+    HIE.ComponentOptions {HIE.componentOptions = flags} <- U.liftIOE compilerOpts >>= unwrapCradleResult "Failed to get compiler options using hie-bios cradle"
+
+    return $
+#if __GLASGOW_HASKELL__ >= 913
+      -- fwrite-if-simplified-core requires a recent bug fix regarding GHCi loading
+      ["-fwrite-if-simplified-core"] ++
+#endif
+      ["--interactive", "-B"++libdir] ++ flags
+
+  U.debugEV _LOG_APP $ show flags
+
   U.liftIOE $ L.debugM _LOG_APP $ "ghci initial prompt [" ++ initPmpt ++ "]."
 
   U.sendConsoleEventLF $ "CWD: " ++ cwd
-  U.sendConsoleEventLF $ "CMD: " ++ L.intercalate " " (cmd : opts)
+  U.sendConsoleEventLF $ "CMD: " ++ L.intercalate " " (cmd:flags)
   U.sendConsoleEventLF ""
 
-  P.startGHCi cmd opts cwd envs
+  P.startGHCi cmd flags cwd envs
+
   U.sendErrorEventLF $ "Now, waiting for an initial prompt(\""++initPmpt++"\")" ++ " from ghci."
   U.sendConsoleEventLF ""
   res <- P.expectInitPmpt initPmpt
 
   updateGHCiVersion res
 
+  return flags
+
   where
+    unwrapCradleResult m = \case
+      HIE.CradleNone     -> panic (error m) "HIE.CradleNone"
+      HIE.CradleFail err -> panic (error m) (unlines $ HIE.cradleErrorStderr err)
+      HIE.CradleSuccess x -> return x
 
+    panic exit m = do
+      U.sendErrorEvent m
+      exit
+
     updateGHCiVersion acc = case parse verParser "getGHCiVersion" (unlines acc) of
       Right v -> do
         U.debugEV _LOG_APP $ "GHCi version is " ++ V.showVersion v
@@ -226,12 +275,16 @@
     return ()
 
 
--- |
---
-loadStarupFile :: AppContext ()
-loadStarupFile = do
+-- | Takes as an argument the list of flags used to invoke GHCi to determine
+-- if the main module has already been loaded. If it hasn't, loads the main file.
+loadStarupFile :: [String] -> AppContext ()
+loadStarupFile flags = do
   file <- view startupAppStores <$> get
-  SU.loadHsFile file
+  when (not $ any (\lf -> lf `L.isSuffixOf` file) flags) $
+    -- We only load the file if it hasn't already been given as an argument;
+    -- Otherwise, we'll force loading the main module and all of its dependencies a second time.
+    -- That is incredibly painful in large projects (like GHC).
+    SU.loadHsFile file
 
   let cmd  = ":dap-context-modules "
 
@@ -240,9 +293,6 @@
 
   return ()
 
-
--- |
---
 addWithGHC :: [String] -> AppContext [String]
 addWithGHC [] = return []
 addWithGHC cmds
@@ -259,7 +309,6 @@
     withGhciExists (x:xs)
       | L.isPrefixOf "--with-ghc=" x = True
       | otherwise = withGhciExists xs
-
 
 -- |
 --
diff --git a/src/Haskell/Debug/Adapter/Watch.hs b/src/Haskell/Debug/Adapter/Watch.hs
new file mode 100644
--- /dev/null
+++ b/src/Haskell/Debug/Adapter/Watch.hs
@@ -0,0 +1,90 @@
+{-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE CPP #-}
+
+module Haskell.Debug.Adapter.Watch where
+
+import Control.Monad.IO.Class
+import qualified System.FSNotify as S
+import Control.Lens
+import Control.Concurrent (threadDelay)
+import Control.Concurrent.MVar
+import Control.Monad.State.Lazy
+import qualified System.Log.Logger as L
+import Control.Monad.Except
+import qualified Data.List as L
+
+import Haskell.Debug.Adapter.Type
+import Haskell.Debug.Adapter.Utility
+import Haskell.Debug.Adapter.Constant
+
+import System.FilePath
+
+#if __GLASGOW_HASKELL__ >= 906
+import Control.Monad
+#endif
+-- |
+--
+run :: AppStores -> IO ()
+run appData = do
+  L.debugM _LOG_WATCH "start watch app"
+  _ <- runApp appData app
+  L.debugM _LOG_WATCH "end watch app"
+
+
+-- |
+--
+app :: AppContext ()
+app = flip catchError errHdl $ do
+  liftIO $ L.infoM _LOG_WATCH "wait getting workspace path."
+  ws <- getWS
+  liftIO $ L.infoM _LOG_WATCH $ "start watching " ++ ws
+
+  reqStore <- view reqStoreAppStores <$> get
+  let conf = S.defaultConfig
+  liftIO $ S.withManagerConf conf $ goIO ws reqStore
+  
+  where
+    -- |
+    --
+    errHdl msg = do
+      criticalEV _LOG_REQUEST msg
+      addEvent CriticalExitEvent
+
+    -- |
+    --
+    goIO ws reqStore mgr = do
+      S.watchTree mgr ws hsFilter (action reqStore)
+      forever $ threadDelay _1_SEC
+
+    -- |
+    --
+    hsFilter ev = (L.isSuffixOf _HS_FILE_EXT (S.eventPath ev))
+               && (not (L.isInfixOf (pathSeparator:".") (S.eventPath ev)))
+
+    -- |
+    --
+    action mvar ev@(S.Added{}) = sendRequest mvar ev
+    action mvar ev@(S.Modified{}) = sendRequest mvar ev
+    action _ _ = return ()
+
+    -- |
+    --
+    sendRequest mvar ev = do
+      L.debugM _LOG_WATCH $ "detect. " ++ show ev
+      let req = WrapRequest $ InternalLoadRequest 
+              $ HdaInternalLoadRequest $ S.eventPath ev
+      reqs <- takeMVar mvar
+      putMVar mvar (req : reqs)
+  
+
+    -- |
+    -- 
+    getWS :: AppContext FilePath
+    getWS = do
+      wsMVar <- view workspaceAppStores <$> get
+      ws <- liftIO $ readMVar wsMVar
+      if not (null ws) then return ws
+        else do
+          liftIO $ threadDelay _1_SEC
+          getWS
+