diff --git a/Cabal/Distribution/Simple/ShowBuildInfo.hs b/Cabal/Distribution/Simple/ShowBuildInfo.hs
index 2a41962fb6e..9375c81efa8 100644
--- a/Cabal/Distribution/Simple/ShowBuildInfo.hs
+++ b/Cabal/Distribution/Simple/ShowBuildInfo.hs
@@ -2,7 +2,7 @@
 -- This module defines a simple JSON-based format for exporting basic
 -- information about a Cabal package and the compiler configuration Cabal
 -- would use to build it. This can be produced with the
--- @cabal new-show-build-info@ command.
+-- @cabal show-build-info@ command.
 --
 --
 -- This format is intended for consumption by external tooling and should
diff --git a/cabal-install/Distribution/Client/CmdBuild.hs b/cabal-install/Distribution/Client/CmdBuild.hs
index d4123b42ef5..702ee9ee531 100644
--- a/cabal-install/Distribution/Client/CmdBuild.hs
+++ b/cabal-install/Distribution/Client/CmdBuild.hs
@@ -8,7 +8,8 @@ module Distribution.Client.CmdBuild (
     -- * Internals exposed for testing
     TargetProblem(..),
     selectPackageTargets,
-    selectComponentTarget
+    selectComponentTarget,
+    reportTargetProblems
   ) where
 
 import Distribution.Client.ProjectOrchestration
diff --git a/cabal-install/Distribution/Client/CmdShowBuildInfo.hs b/cabal-install/Distribution/Client/CmdShowBuildInfo.hs
index cc5a41bb6cc..311595ca022 100644
--- a/cabal-install/Distribution/Client/CmdShowBuildInfo.hs
+++ b/cabal-install/Distribution/Client/CmdShowBuildInfo.hs
@@ -1,27 +1,41 @@
--- | cabal-install CLI command: build
+-- | cabal-install CLI command: show-build-info
 --
-module Distribution.Client.CmdShowBuildInfo (
-    -- * The @build@ CLI and action
-    showBuildInfoCommand,
-    showBuildInfoAction
-  ) where
+module Distribution.Client.CmdShowBuildInfo where
+-- (
+--     -- * The @show-build-info@ CLI and action
+--     showBuildInfoCommand,
+--     showBuildInfoAction
+--   )
 
+import Distribution.Client.Compat.Prelude
+         ( when, find, fromMaybe )
 import Distribution.Client.ProjectOrchestration
 import Distribution.Client.CmdErrorMessages
 import Distribution.Client.CmdInstall.ClientInstallFlags
 
 import Distribution.Client.Setup
-         ( GlobalFlags, ConfigFlags(..), ConfigExFlags, InstallFlags )
+         ( GlobalFlags, ConfigFlags(..), ConfigExFlags, InstallFlags
+         )
 import qualified Distribution.Client.Setup as Client
 import Distribution.Simple.Setup
-         ( HaddockFlags, fromFlagOrDefault, TestFlags )
+         ( HaddockFlags, TestFlags
+         , fromFlagOrDefault
+         )
 import Distribution.Simple.Command
-         ( CommandUI(..), usageAlternatives )
+         ( CommandUI(..), option, reqArg', usageAlternatives
+         )
 import Distribution.Verbosity
          ( Verbosity, silent )
 import Distribution.Simple.Utils
-         ( wrapText, die')
-import Distribution.Types.UnitId (UnitId)
+         ( wrapText, die', withTempDirectory )
+import Distribution.Types.UnitId
+         ( UnitId, mkUnitId )
+import Distribution.Types.Version
+         ( mkVersion )
+import Distribution.Types.PackageDescription
+         ( buildType )
+import Distribution.Deprecated.Text
+         ( display )
 
 import qualified Data.Map as Map
 import qualified Distribution.Simple.Setup as Cabal
@@ -31,67 +45,78 @@ import qualified Distribution.Client.InstallPlan as InstallPlan
 import Distribution.Client.ProjectPlanning.Types
 import Distribution.Client.ProjectPlanning (
   setupHsConfigureFlags, setupHsConfigureArgs,
-  setupHsBuildFlags, setupHsBuildArgs, 
+  setupHsBuildFlags, setupHsBuildArgs,
   setupHsScriptOptions
   )
 import Distribution.Client.DistDirLayout (distBuildDirectory)
 import Distribution.Client.Types ( PackageLocation(..), GenericReadyPackage(..) )
 import Distribution.Client.JobControl (newLock, Lock)
 import Distribution.Simple.Configure (tryGetPersistBuildConfig)
-import Data.List (find)
+import qualified Distribution.Client.CmdInstall as CmdInstall
 
-showBuildInfoCommand :: CommandUI (ConfigFlags, ConfigExFlags, InstallFlags, HaddockFlags, TestFlags)
-showBuildInfoCommand = Client.installCommand {
-  commandName         = "new-show-build-info",
+import System.Directory (getTemporaryDirectory)
+import System.FilePath ((</>))
+
+showBuildInfoCommand :: CommandUI ShowBuildInfoFlags
+showBuildInfoCommand = CmdInstall.installCommand {
+  commandName         = "show-build-info",
   commandSynopsis     = "Show project build information",
-  commandUsage        = usageAlternatives "new-show-build-info" [ "[TARGETS] [FLAGS]" ],
+  commandUsage        = usageAlternatives "show-build-info" [ "[TARGETS] [FLAGS]" ],
   commandDescription  = Just $ \_ -> wrapText $
-        "Build one or more targets from within the project. The available "
-     ++ "targets are the packages in the project as well as individual "
-     ++ "components within those packages, including libraries, executables, "
-     ++ "test-suites or benchmarks. Targets can be specified by name or "
-     ++ "location. If no target is specified then the default is to build "
-     ++ "the package in the current directory.\n\n"
-
-     ++ "Dependencies are built or rebuilt as necessary. Additional "
-     ++ "configuration flags can be specified on the command line and these "
-     ++ "extend the project configuration from the 'cabal.project', "
-     ++ "'cabal.project.local' and other files.",
+        "Provides detailed json output for the given package.\n"
+     ++ "Contains information about the different build components and compiler flags.\n",
   commandNotes        = Just $ \pname ->
         "Examples:\n"
-     ++ "  " ++ pname ++ " new-build\n"
-     ++ "    Build the package in the current directory or all packages in the project\n"
-     ++ "  " ++ pname ++ " new-build pkgname\n"
-     ++ "    Build the package named pkgname in the project\n"
-     ++ "  " ++ pname ++ " new-build ./pkgfoo\n"
-     ++ "    Build the package in the ./pkgfoo directory\n"
-     ++ "  " ++ pname ++ " new-build cname\n"
-     ++ "    Build the component named cname module Distribution.Client.InstallPlanin the project\n"
-     ++ "  " ++ pname ++ " new-build cname --module Distribution.Client.InstallPlanenable-profiling\n"
-     ++ "    Build the component in profilingmodule Distribution.Client.InstallPlan mode (including dependencies as needed)\n\n"
-
-     ++ cmdCommonHelpTextNewBuildBeta
+     ++ "  " ++ pname ++ " show-build-info\n"
+     ++ "    Shows build information about the current package\n"
+     ++ "  " ++ pname ++ " show-build-info .\n"
+     ++ "    Shows build information about the current package\n"
+     ++ "  " ++ pname ++ " show-build-info ./pkgname \n"
+     ++ "    Shows build information about the package located in './pkgname'\n"
+     ++ cmdCommonHelpTextNewBuildBeta,
+  commandOptions = \showOrParseArgs ->
+      Client.liftOptions buildInfoInstallCommandFlags (\pf flags -> flags { buildInfoInstallCommandFlags = pf }) (commandOptions CmdInstall.installCommand showOrParseArgs)
+      ++
+      [ option [] ["buildinfo-json-output"]
+              "Write the result to the given file instead of stdout"
+              buildInfoOutputFile (\pf flags -> flags { buildInfoOutputFile = pf })
+              (reqArg' "FILE" Just (maybe [] pure)),
+        option [] ["unit-ids-json"]
+              "Show build-info only for selected unit-id's."
+              buildInfoUnitIds (\pf flags -> flags { buildInfoUnitIds = pf })
+              (reqArg' "UNIT-ID" (Just . words) (fromMaybe []))
+      ],
+  commandDefaultFlags = defaultShowBuildInfoFlags
+
    }
 
+data ShowBuildInfoFlags = ShowBuildInfoFlags
+    { buildInfoInstallCommandFlags :: (ConfigFlags, ConfigExFlags, InstallFlags, HaddockFlags, TestFlags, ClientInstallFlags)
+    , buildInfoOutputFile :: Maybe FilePath
+    , buildInfoUnitIds :: Maybe [String]
+    }
+
+defaultShowBuildInfoFlags :: ShowBuildInfoFlags
+defaultShowBuildInfoFlags = ShowBuildInfoFlags
+    { buildInfoInstallCommandFlags = (mempty, mempty, mempty, mempty, mempty, mempty)
+    , buildInfoOutputFile = Nothing
+    , buildInfoUnitIds = Nothing
+    }
 
--- | The @build@ command does a lot. It brings the install plan up to date,
+-- | The @show-build-info@ command does a lot. It brings the install plan up to date,
 -- selects that part of the plan needed by the given or implicit targets and
 -- then executes the plan.
 --
 -- For more details on how this works, see the module
 -- "Distribution.Client.ProjectOrchestration"
 --
-showBuildInfoAction :: (ConfigFlags, ConfigExFlags, InstallFlags, HaddockFlags, TestFlags)
-            -> [String] -> GlobalFlags -> IO ()
-showBuildInfoAction (configFlags, configExFlags, installFlags, haddockFlags, testFlags)
-            targetStrings globalFlags = do
-
-  baseCtx <- establishProjectBaseContext verbosity cliConfig
-  let baseCtx' = baseCtx {
-                    buildSettings = (buildSettings baseCtx) {
-                      buildSettingDryRun = True
-                    }
-                  }
+showBuildInfoAction :: ShowBuildInfoFlags -> [String] -> GlobalFlags -> IO ()
+showBuildInfoAction (ShowBuildInfoFlags (configFlags, configExFlags, installFlags, haddockFlags, testFlags, clientInstallFlags) fileOutput unitIds)
+  targetStrings globalFlags = do
+  baseCtx <- establishProjectBaseContext verbosity cliConfig OtherCommand
+  let baseCtx' = baseCtx
+        { buildSettings = (buildSettings baseCtx) { buildSettingDryRun = True }
+        }
 
   targetSelectors <- either (reportTargetSelectorProblems verbosity) return
                   =<< readTargetSelectors (localPackages baseCtx') Nothing targetStrings
@@ -113,79 +138,127 @@ showBuildInfoAction (configFlags, configExFlags, installFlags, haddockFlags, tes
       return (elaboratedPlan, targets)
 
   scriptLock <- newLock
-  showTargets verbosity baseCtx' buildCtx scriptLock
-  
+  showTargets fileOutput unitIds verbosity baseCtx' buildCtx scriptLock
   where
     -- Default to silent verbosity otherwise it will pollute our json output
     verbosity = fromFlagOrDefault silent (configVerbosity configFlags)
     cliConfig = commandLineFlagsToProjectConfig
                   globalFlags configFlags configExFlags
-                  installFlags defaultClientInstallFlags
+                  installFlags clientInstallFlags
                   haddockFlags
                   testFlags
 
 -- Pretty nasty piecemeal out of json, but I can't see a way to retrieve output of the setupWrapper'd tasks
-showTargets :: Verbosity -> ProjectBaseContext -> ProjectBuildContext -> Lock -> IO ()
-showTargets verbosity baseCtx buildCtx lock = do
-  putStr "["
-  mapM_ showSeparated (zip [0..] targets)
-  putStrLn "]"
+showTargets :: Maybe FilePath -> Maybe [String] -> Verbosity -> ProjectBaseContext -> ProjectBuildContext -> Lock -> IO ()
+showTargets fileOutput unitIds verbosity baseCtx buildCtx lock = do
+  tempDir <- getTemporaryDirectory
+  withTempDirectory verbosity tempDir "show-build-info" $ \dir -> do
+    mapM_ (doShowInfo dir) targets
+    case fileOutput of
+      Nothing -> outputResult dir putStr targets
+      Just fp -> do
+        writeFile fp ""
+        outputResult dir (appendFile fp) targets
+
     where configured = [p | InstallPlan.Configured p <- InstallPlan.toList (elaboratedPlanOriginal buildCtx)]
-          targets = fst <$> (Map.toList . targetsMap $ buildCtx)
-          doShowInfo unitId = showInfo verbosity baseCtx buildCtx lock configured unitId
-          showSeparated (idx, unitId)
-              | idx == length targets - 1 = doShowInfo unitId
-              | otherwise = doShowInfo unitId >> putStrLn "," 
-
-showInfo :: Verbosity -> ProjectBaseContext -> ProjectBuildContext -> Lock -> [ElaboratedConfiguredPackage] -> UnitId -> IO ()
-showInfo verbosity baseCtx buildCtx lock pkgs targetUnitId
-  | Nothing <- mbPkg = die' verbosity $ "No unit " ++ show targetUnitId 
-  | Just pkg <- mbPkg = do
-    let shared = elaboratedShared buildCtx
-        install = elaboratedPlanOriginal buildCtx
-        dirLayout = distDirLayout baseCtx
-        buildDir = distBuildDirectory dirLayout (elabDistDirParams shared pkg)
-        flags = setupHsBuildFlags pkg shared verbosity buildDir
-        args = setupHsBuildArgs pkg
-        srcDir = case (elabPkgSourceLocation pkg) of
-          LocalUnpackedPackage fp -> fp
-          _ -> ""
-        scriptOptions = setupHsScriptOptions 
-            (ReadyPackage pkg) 
-            install 
-            shared 
-            dirLayout
-            srcDir 
-            buildDir 
-            False 
-            lock
-        configureFlags = setupHsConfigureFlags (ReadyPackage pkg) shared verbosity buildDir
-        configureArgs = setupHsConfigureArgs pkg
-    --Configure the package if there's no existing config
-    lbi <- tryGetPersistBuildConfig buildDir
-    case lbi of
-      Left _ -> setupWrapper 
-                  verbosity 
-                  scriptOptions 
-                  (Just $ elabPkgDescription pkg) 
-                  (Cabal.configureCommand defaultProgramDb) 
-                  (const $ configureFlags)
-                  (const configureArgs)
-      Right _ -> pure ()
-    setupWrapper 
-      verbosity 
-      scriptOptions 
-      (Just $ elabPkgDescription pkg) 
-      (Cabal.showBuildInfoCommand defaultProgramDb) 
-      (const flags) 
-      (const args)
-    where mbPkg = find ((targetUnitId ==) . elabUnitId) pkgs
-
--- | This defines what a 'TargetSelector' means for the @write-autogen-files@ command.
+          targets = maybe (fst <$> (Map.toList . targetsMap $ buildCtx)) (map mkUnitId) unitIds
+          doShowInfo :: FilePath -> UnitId -> IO ()
+          doShowInfo dir unitId =
+              showInfo
+                (dir </> unitIdToFilePath unitId)
+                verbosity
+                baseCtx
+                buildCtx
+                lock
+                configured
+                unitId
+
+          outputResult :: FilePath -> (String -> IO ()) -> [UnitId] -> IO ()
+          outputResult dir printer units = do
+              let unroll [] = return ()
+                  unroll [x] = do
+                    content <- readFile (dir </> unitIdToFilePath x)
+                    printer content
+                  unroll (x:xs) = do
+                    content <- readFile (dir </> unitIdToFilePath x)
+                    printer content
+                    printer ","
+                    unroll xs
+              printer "["
+              unroll units
+              printer "]"
+
+          unitIdToFilePath :: UnitId -> FilePath
+          unitIdToFilePath unitId = "build-info-" ++ display unitId ++ ".json"
+
+showInfo :: FilePath -> Verbosity -> ProjectBaseContext -> ProjectBuildContext -> Lock -> [ElaboratedConfiguredPackage] -> UnitId -> IO ()
+showInfo fileOutput verbosity baseCtx buildCtx lock pkgs targetUnitId =
+  case mbPkg of
+    Nothing -> die' verbosity $ "No unit " ++ display targetUnitId
+    Just pkg -> do
+      let shared = elaboratedShared buildCtx
+          install = elaboratedPlanOriginal buildCtx
+          dirLayout = distDirLayout baseCtx
+          buildDir = distBuildDirectory dirLayout (elabDistDirParams shared pkg)
+          buildType' = buildType (elabPkgDescription pkg)
+          flags = setupHsBuildFlags pkg shared verbosity buildDir
+          args = setupHsBuildArgs pkg
+          srcDir = case (elabPkgSourceLocation pkg) of
+            LocalUnpackedPackage fp -> fp
+            _ -> ""
+          scriptOptions = setupHsScriptOptions
+              (ReadyPackage pkg)
+              install
+              shared
+              dirLayout
+              srcDir
+              buildDir
+              False
+              lock
+          configureFlags = setupHsConfigureFlags (ReadyPackage pkg) shared verbosity buildDir
+          configureArgs = setupHsConfigureArgs pkg
+
+      -- check cabal version is corrct
+      (cabalVersion, _, _) <- getSetupMethod verbosity scriptOptions
+                                            (elabPkgDescription pkg) buildType'
+      when (cabalVersion < mkVersion [3, 0, 0,0])
+        ( die' verbosity $ "Only a Cabal version >= 3.0.0.0 is supported for this command.\n"
+              ++ "Found version: " ++ display cabalVersion ++ "\n"
+              ++ "For component: " ++ display targetUnitId
+        )
+      --Configure the package if there's no existing config
+      lbi <- tryGetPersistBuildConfig buildDir
+      case lbi of
+        Left _ -> setupWrapper
+                    verbosity
+                    scriptOptions
+                    (Just $ elabPkgDescription pkg)
+                    (Cabal.configureCommand defaultProgramDb)
+                    (const configureFlags)
+                    (const configureArgs)
+        Right _ -> pure ()
+
+      setupWrapper
+        verbosity
+        scriptOptions
+        (Just $ elabPkgDescription pkg)
+        (Cabal.showBuildInfoCommand defaultProgramDb)
+        (const (Cabal.ShowBuildInfoFlags
+          { Cabal.buildInfoBuildFlags = flags
+          , Cabal.buildInfoOutputFile = Just fileOutput
+          }
+          )
+        )
+        (const args)
+    where
+      mbPkg :: Maybe ElaboratedConfiguredPackage
+      mbPkg = find ((targetUnitId ==) . elabUnitId) pkgs
+
+-- | This defines what a 'TargetSelector' means for the @show-build-info@ command.
 -- It selects the 'AvailableTarget's that the 'TargetSelector' refers to,
 -- or otherwise classifies the problem.
 --
--- For the @write-autogen-files@ command select all components except non-buildable and disabled
+-- For the @show-build-info@ command select all components except non-buildable and disabled
 -- tests\/benchmarks, fail if there are no such components
 --
 selectPackageTargets :: TargetSelector
@@ -219,7 +292,7 @@ selectPackageTargets targetSelector targets
 -- | For a 'TargetComponent' 'TargetSelector', check if the component can be
 -- selected.
 --
--- For the @build@ command we just need the basic checks on being buildable etc.
+-- For the @show-build-info@ command we just need the basic checks on being buildable etc.
 --
 selectComponentTarget :: SubComponentTarget
                       -> AvailableTarget k -> Either TargetProblem k
@@ -229,7 +302,7 @@ selectComponentTarget subtarget =
 
 
 -- | The various error conditions that can occur when matching a
--- 'TargetSelector' against 'AvailableTarget's for the @build@ command.
+-- 'TargetSelector' against 'AvailableTarget's for the @show-build-info@ command.
 --
 data TargetProblem =
      TargetProblemCommon       TargetProblemCommon
@@ -251,4 +324,4 @@ renderTargetProblem (TargetProblemCommon problem) =
 renderTargetProblem (TargetProblemNoneEnabled targetSelector targets) =
     renderTargetProblemNoneEnabled "build" targetSelector targets
 renderTargetProblem(TargetProblemNoTargets targetSelector) =
-    renderTargetProblemNoTargets "build" targetSelector
\ No newline at end of file
+    renderTargetProblemNoTargets "build" targetSelector
diff --git a/cabal-install/Distribution/Client/CmdWriteAutogenFiles.hs b/cabal-install/Distribution/Client/CmdWriteAutogenFiles.hs
deleted file mode 100644
index 86a80b6fa53..00000000000
--- a/cabal-install/Distribution/Client/CmdWriteAutogenFiles.hs
+++ /dev/null
@@ -1,220 +0,0 @@
--- | cabal-install CLI command: build
---
-module Distribution.Client.CmdWriteAutogenFiles (
-    -- * The @build@ CLI and action
-    writeAutogenFilesCommand,
-    writeAutogenFilesAction
-  ) where
-
-import Distribution.Client.ProjectOrchestration
-import Distribution.Client.CmdErrorMessages
-import Distribution.Client.CmdInstall.ClientInstallFlags
-
-import Distribution.Client.Setup
-         ( GlobalFlags, ConfigFlags(..), ConfigExFlags, InstallFlags, WriteAutogenFilesFlags(..) )
-import qualified Distribution.Client.Setup as Client
-import Distribution.Simple.Setup
-         ( HaddockFlags, fromFlagOrDefault, Flag(..), TestFlags )
-import Distribution.Simple.Command
-         ( CommandUI(..), usageAlternatives )
-import Distribution.Verbosity
-         ( Verbosity, normal )
-import Distribution.Simple.Utils
-         ( wrapText, die' )
-import Distribution.Simple.Configure (tryGetPersistBuildConfig)
-
-import qualified Data.Map as Map
-import qualified Distribution.Simple.Setup as Cabal
-import Distribution.Client.SetupWrapper
-import Distribution.Simple.Program ( defaultProgramDb )
-import qualified Distribution.Client.InstallPlan as InstallPlan
-import Distribution.Client.ProjectPlanning.Types
-import Distribution.Client.ProjectPlanning (
-  setupHsScriptOptions, setupHsConfigureFlags, setupHsConfigureArgs
-  )
-import Distribution.Client.DistDirLayout (distBuildDirectory)
-import Distribution.Client.Types ( PackageLocation(..), GenericReadyPackage(..) )
-import Distribution.Client.JobControl (newLock, Lock)
-
-writeAutogenFilesCommand :: CommandUI (ConfigFlags, ConfigExFlags, InstallFlags, HaddockFlags, TestFlags)
-writeAutogenFilesCommand = Client.installCommand {
-  commandName         = "new-write-autogen-files",
-  commandSynopsis     = "",
-  commandUsage        = usageAlternatives "new-write-autogen-files" [ "[FLAGS]" ],
-  commandDescription  = Just $ \_ -> wrapText $ 
-        "Generate and write out the Paths_<pkg>.hs and cabal_macros.h files\n"
-     ++ "for all components in the project",
-  commandNotes        = Just $ \pname ->
-        "Examples:\n"
-     ++ "  " ++ pname ++ " new-write-autogen-files\n"
-     ++ "    Write for all packages in the project\n"
-  }
-
-writeAutogenFilesAction :: (ConfigFlags, ConfigExFlags, InstallFlags, HaddockFlags, TestFlags) 
-                            -> [String] -> GlobalFlags -> IO ()
-writeAutogenFilesAction (configFlags, configExFlags, installFlags, haddockFlags, testFlags)
-  targetStrings globalFlags = do
-    baseCtx <- establishProjectBaseContext verbosity cliConfig
-    let baseCtx' = baseCtx {
-                      buildSettings = (buildSettings baseCtx) {
-                        buildSettingDryRun = True
-                      }
-                    }
-    targetSelectors <- either (reportTargetSelectorProblems verbosity) return
-                    =<< readTargetSelectors (localPackages baseCtx') Nothing targetStrings
-
-    buildCtx <-
-      runProjectPreBuildPhase verbosity baseCtx $ \elaboratedPlan -> do
-          -- Interpret the targets on the command line as build targets
-          -- (as opposed to say repl or haddock targets).
-          targets <- either (reportTargetProblems verbosity) return
-                    $ resolveTargets
-                        selectPackageTargets
-                        selectComponentTarget
-                        TargetProblemCommon
-                        elaboratedPlan
-                        Nothing
-                        targetSelectors
-
-          let elaboratedPlan' = pruneInstallPlanToTargets
-                                  TargetActionBuild
-                                  targets
-                                  elaboratedPlan
-          elaboratedPlan'' <-
-            if buildSettingOnlyDeps (buildSettings baseCtx')
-              then either (reportCannotPruneDependencies verbosity) return $
-                    pruneInstallPlanToDependencies (Map.keysSet targets)
-                                                  elaboratedPlan'
-              else return elaboratedPlan'
-
-          return (elaboratedPlan'', targets)
-
-    scriptLock <- newLock
-    writeAutogenFiles verbosity baseCtx' buildCtx scriptLock (configured buildCtx)
-    
-    where
-      verbosity = fromFlagOrDefault normal (configVerbosity configFlags)
-      cliConfig = commandLineFlagsToProjectConfig
-                    globalFlags configFlags configExFlags
-                    installFlags defaultClientInstallFlags
-                    haddockFlags
-                    testFlags
-      configured ctx = [p | InstallPlan.Configured p <- InstallPlan.toList (elaboratedPlanToExecute ctx)]
-
-
-writeAutogenFiles :: Verbosity -> ProjectBaseContext -> ProjectBuildContext -> Lock -> [ElaboratedConfiguredPackage] -> IO ()
-writeAutogenFiles verbosity baseCtx buildCtx lock pkgs = mapM_ runWrapper pkgs
-  where runWrapper pkg = do
-          let shared = elaboratedShared buildCtx
-              install = elaboratedPlanOriginal buildCtx
-              dirLayout = distDirLayout baseCtx
-              buildDir = distBuildDirectory dirLayout (elabDistDirParams shared pkg)
-              srcDir = case (elabPkgSourceLocation pkg) of
-                LocalUnpackedPackage fp -> fp
-                _ -> ""
-              scriptOptions = setupHsScriptOptions 
-                  (ReadyPackage pkg) 
-                  install 
-                  shared 
-                  dirLayout
-                  srcDir 
-                  buildDir 
-                  False 
-                  lock
-              configureFlags = setupHsConfigureFlags (ReadyPackage pkg) shared verbosity buildDir
-              configureArgs = setupHsConfigureArgs pkg
-          --Configure the package if there's no existing config, 
-          lbi <- tryGetPersistBuildConfig buildDir
-          case lbi of
-            Left _ -> setupWrapper 
-                        verbosity 
-                        scriptOptions 
-                        (Just $ elabPkgDescription pkg) 
-                        (Cabal.configureCommand defaultProgramDb) 
-                        (const $ configureFlags)
-                        (const configureArgs)
-            Right _ -> pure ()
-          setupWrapper 
-            verbosity 
-            scriptOptions 
-            (Just $ elabPkgDescription pkg) 
-            (Cabal.writeAutogenFilesCommand defaultProgramDb) 
-            (const $ WriteAutogenFilesFlags (Flag buildDir) (Flag verbosity))
-            (const [])
-
--- | This defines what a 'TargetSelector' means for the @write-autogen-files@ command.
--- It selects the 'AvailableTarget's that the 'TargetSelector' refers to,
--- or otherwise classifies the problem.
---
--- For the @write-autogen-files@ command select all components except non-buildable and disabled
--- tests\/benchmarks, fail if there are no such components
---
-selectPackageTargets :: TargetSelector
-                     -> [AvailableTarget k] -> Either TargetProblem [k]
-selectPackageTargets targetSelector targets
-
-    -- If there are any buildable targets then we select those
-  | not (null targetsBuildable)
-  = Right targetsBuildable
-
-    -- If there are targets but none are buildable then we report those
-  | not (null targets)
-  = Left (TargetProblemNoneEnabled targetSelector targets')
-
-    -- If there are no targets at all then we report that
-  | otherwise
-  = Left (TargetProblemNoTargets targetSelector)
-  where
-    targets'         = forgetTargetsDetail targets
-    targetsBuildable = selectBuildableTargetsWith
-                         (buildable targetSelector)
-                         targets
-
-    -- When there's a target filter like "pkg:tests" then we do select tests,
-    -- but if it's just a target like "pkg" then we don't build tests unless
-    -- they are requested by default (i.e. by using --enable-tests)
-    buildable (TargetPackage _ _  Nothing) TargetNotRequestedByDefault = False
-    buildable (TargetAllPackages  Nothing) TargetNotRequestedByDefault = False
-    buildable _ _ = True
-
--- | For a 'TargetComponent' 'TargetSelector', check if the component can be
--- selected.
---
--- For the @build@ command we just need the basic checks on being buildable etc.
---
-selectComponentTarget :: SubComponentTarget
-                      -> AvailableTarget k -> Either TargetProblem k
-selectComponentTarget subtarget =
-    either (Left . TargetProblemCommon) Right
-  . selectComponentTargetBasic subtarget
-
-
--- | The various error conditions that can occur when matching a
--- 'TargetSelector' against 'AvailableTarget's for the @build@ command.
---
-data TargetProblem =
-     TargetProblemCommon       TargetProblemCommon
-
-     -- | The 'TargetSelector' matches targets but none are buildable
-   | TargetProblemNoneEnabled TargetSelector [AvailableTarget ()]
-
-     -- | There are no targets at all
-   | TargetProblemNoTargets   TargetSelector
-  deriving (Eq, Show)
-
-reportTargetProblems :: Verbosity -> [TargetProblem] -> IO a
-reportTargetProblems verbosity =
-    die' verbosity . unlines . map renderTargetProblem
-
-renderTargetProblem :: TargetProblem -> String
-renderTargetProblem (TargetProblemCommon problem) =
-    renderTargetProblemCommon "build" problem
-renderTargetProblem (TargetProblemNoneEnabled targetSelector targets) =
-    renderTargetProblemNoneEnabled "build" targetSelector targets
-renderTargetProblem(TargetProblemNoTargets targetSelector) =
-    renderTargetProblemNoTargets "build" targetSelector
-
-reportCannotPruneDependencies :: Verbosity -> CannotPruneDependencies -> IO a
-reportCannotPruneDependencies verbosity =
-    die' verbosity . renderCannotPruneDependencies
-
diff --git a/cabal-install/Distribution/Client/Setup.hs b/cabal-install/Distribution/Client/Setup.hs
index a2f06f789c9..e482ce67d5c 100644
--- a/cabal-install/Distribution/Client/Setup.hs
+++ b/cabal-install/Distribution/Client/Setup.hs
@@ -56,10 +56,7 @@ module Distribution.Client.Setup
     , doctestCommand
     , copyCommand
     , registerCommand
-
-    --ghc-mod support commands
-    , showBuildInfoCommand
-    , writeAutogenFilesCommand, WriteAutogenFilesFlags(..)
+    --, showBuildInfoCommand
     , parsePackageArgs
     , liftOptions
     , yesNoOpt
@@ -108,7 +105,6 @@ import Distribution.Simple.Setup
          , SDistFlags(..), HaddockFlags(..)
          , CleanFlags(..), DoctestFlags(..)
          , CopyFlags(..), RegisterFlags(..)
-         , WriteAutogenFilesFlags(..)
          , readPackageDbList, showPackageDbList
          , Flag(..), toFlag, flagToMaybe, flagToList, maybeToFlag
          , BooleanFlag(..), optionVerbosity
@@ -202,7 +198,6 @@ globalCommand commands = CommandUI {
           , "haddock"
           , "hscolour"
           , "show-build-info"
-          , "write-autogen-files"
           , "exec"
           , "new-build"
           , "new-configure"
@@ -290,7 +285,6 @@ globalCommand commands = CommandUI {
         , addCmd "report"
         , par
         , addCmd "show-build-info"
-        , addCmd "write-autogen-files"
         , addCmd "freeze"
         , addCmd "gen-bounds"
         , addCmd "outdated"
@@ -869,25 +863,6 @@ filterTestFlags flags cabalLibVersion
       Cabal.testWrapper = NoFlag
       }
 
--- ------------------------------------------------------------
--- * show-build-info command
--- ------------------------------------------------------------
-
-showBuildInfoCommand :: CommandUI (BuildFlags, BuildExFlags)
-showBuildInfoCommand = parent {
-    commandDefaultFlags = (commandDefaultFlags parent, mempty),
-    commandOptions      =
-      \showOrParseArgs -> liftOptions fst setFst
-                          (commandOptions parent showOrParseArgs)
-                          ++
-                          liftOptions snd setSnd (buildExOptions showOrParseArgs)
-  }
-  where
-    setFst a (_,b) = (a,b)
-    setSnd b (a,_) = (a,b)
-
-    parent = Cabal.showBuildInfoCommand defaultProgramDb
-
 -- ------------------------------------------------------------
 -- * Repl command
 -- ------------------------------------------------------------
@@ -3012,10 +2987,10 @@ relevantConfigValuesText vs =
 
 
 -- ------------------------------------------------------------
--- * Commands to support ghc-mod
+-- * Commands to support show-build-info
 -- ------------------------------------------------------------
 
-showBuildInfoCommand :: CommandUI (BuildFlags, BuildExFlags)
+showBuildInfoCommand :: CommandUI (Cabal.ShowBuildInfoFlags, BuildExFlags)
 showBuildInfoCommand = parent {
     commandDefaultFlags = (commandDefaultFlags parent, mempty),
     commandOptions      =
@@ -3029,6 +3004,3 @@ showBuildInfoCommand = parent {
     setSnd b (a,_) = (a,b)
 
     parent = Cabal.showBuildInfoCommand defaultProgramDb
-
-writeAutogenFilesCommand :: CommandUI WriteAutogenFilesFlags
-writeAutogenFilesCommand = Cabal.writeAutogenFilesCommand defaultProgramDb
\ No newline at end of file
diff --git a/cabal-install/Distribution/Client/SetupWrapper.hs b/cabal-install/Distribution/Client/SetupWrapper.hs
index d422a2fddfb..955ac3b0c11 100644
--- a/cabal-install/Distribution/Client/SetupWrapper.hs
+++ b/cabal-install/Distribution/Client/SetupWrapper.hs
@@ -17,7 +17,7 @@
 -- runs it with the given arguments.
 
 module Distribution.Client.SetupWrapper (
-    getSetup, runSetup, runSetupCommand, setupWrapper,
+    getSetup, runSetup, runSetupCommand, setupWrapper, getSetupMethod,
     SetupScriptOptions(..),
     defaultSetupScriptOptions,
   ) where
diff --git a/cabal-install/cabal-install.cabal b/cabal-install/cabal-install.cabal
index b02289a5314..fde55eaaf96 100644
--- a/cabal-install/cabal-install.cabal
+++ b/cabal-install/cabal-install.cabal
@@ -161,8 +161,6 @@ executable cabal
         Distribution.Client.CmdBench
         Distribution.Client.CmdBuild
         Distribution.Client.CmdClean
-        Distribution.Client.CmdShowBuildInfo
-        Distribution.Client.CmdWriteAutogenFiles
         Distribution.Client.CmdConfigure
         Distribution.Client.CmdUpdate
         Distribution.Client.CmdErrorMessages
@@ -173,6 +171,7 @@ executable cabal
         Distribution.Client.CmdInstall.ClientInstallFlags
         Distribution.Client.CmdRepl
         Distribution.Client.CmdRun
+        Distribution.Client.CmdShowBuildInfo
         Distribution.Client.CmdTest
         Distribution.Client.CmdLegacy
         Distribution.Client.CmdSdist
diff --git a/cabal-install/cabal-install.cabal.pp b/cabal-install/cabal-install.cabal.pp
index 0f4d208b02d..df3d56b873d 100644
--- a/cabal-install/cabal-install.cabal.pp
+++ b/cabal-install/cabal-install.cabal.pp
@@ -100,6 +100,7 @@
         Distribution.Client.CmdInstall.ClientInstallFlags
         Distribution.Client.CmdRepl
         Distribution.Client.CmdRun
+        Distribution.Client.CmdShowBuildInfo
         Distribution.Client.CmdTest
         Distribution.Client.CmdLegacy
         Distribution.Client.CmdSdist
diff --git a/cabal-install/main/Main.hs b/cabal-install/main/Main.hs
index a55fe9fc979..ef8f9dbf72a 100644
--- a/cabal-install/main/Main.hs
+++ b/cabal-install/main/Main.hs
@@ -52,7 +52,6 @@ import Distribution.Client.Setup
          , doctestCommand
          , copyCommand
          , registerCommand
-         , WriteAutogenFilesFlags(..)
          )
 import Distribution.Simple.Setup
          ( HaddockTarget(..)
@@ -85,7 +84,6 @@ import qualified Distribution.Client.CmdConfigure as CmdConfigure
 import qualified Distribution.Client.CmdUpdate    as CmdUpdate
 import qualified Distribution.Client.CmdBuild     as CmdBuild
 import qualified Distribution.Client.CmdShowBuildInfo as CmdShowBuildInfo
-import qualified Distribution.Client.CmdWriteAutogenFiles as CmdWriteAutogenFiles
 import qualified Distribution.Client.CmdRepl      as CmdRepl
 import qualified Distribution.Client.CmdFreeze    as CmdFreeze
 import qualified Distribution.Client.CmdHaddock   as CmdHaddock
@@ -158,7 +156,7 @@ import qualified Distribution.Simple as Simple
 import qualified Distribution.Make as Make
 import qualified Distribution.Types.UnqualComponentName as Make
 import Distribution.Simple.Build
-         ( startInterpreter, initialBuildSteps )
+         ( startInterpreter )
 import Distribution.Simple.Command
          ( CommandParse(..), CommandUI(..), Command, CommandSpec(..)
          , CommandType(..), commandsRun, commandAddAction, hiddenCommand
@@ -181,7 +179,7 @@ import Distribution.Simple.Utils
 import Distribution.Text
          ( display )
 import Distribution.Verbosity as Verbosity
-         ( Verbosity, normal, silent )
+         ( Verbosity, normal )
 import Distribution.Version
          ( Version, mkVersion, orLaterVersion )
 import qualified Paths_cabal_install (version)
@@ -307,11 +305,8 @@ mainWorker args = do
       , hiddenCmd  win32SelfUpgradeCommand win32SelfUpgradeAction
       , hiddenCmd  actAsSetupCommand actAsSetupAction
       , hiddenCmd  manpageCommand (manpageAction commandSpecs)
-      -- ghc-mod supporting commands
       , hiddenCmd CmdShowBuildInfo.showBuildInfoCommand
                     CmdShowBuildInfo.showBuildInfoAction
-      , hiddenCmd CmdWriteAutogenFiles.writeAutogenFilesCommand
-                    CmdWriteAutogenFiles.writeAutogenFilesAction
       ] ++ concat
       [ newCmd  CmdConfigure.configureCommand CmdConfigure.configureAction
       , newCmd  CmdUpdate.updateCommand       CmdUpdate.updateAction
@@ -461,13 +456,14 @@ buildAction flags@(buildFlags, _) = buildActionForCommand
   flags
   where verbosity = fromFlagOrDefault normal (buildVerbosity buildFlags)
 
-showBuildInfoAction :: (BuildFlags, BuildExFlags) -> [String] -> Action
-showBuildInfoAction flags@(buildFlags, _) = buildActionForCommand
-  (Cabal.showBuildInfoCommand defaultProgramDb)
-  verbosity
-  flags
-    -- Default silent verbosity so as not to pollute json output
-  where verbosity = fromFlagOrDefault silent (buildVerbosity buildFlags)
+-- showBuildInfoAction :: (Cabal.ShowBuildInfoFlags, BuildExFlags) -> [String] -> Action
+-- showBuildInfoAction (showBuildInfoFlags, buildEx) = buildActionForCommand
+--   (Cabal.showBuildInfoCommand defaultProgramDb)
+--   showBuildInfoFlags
+--   verbosity
+--   (Cabal.buildInfoBuildFlags showBuildInfoFlags, buildEx)
+--     -- Default silent verbosity so as not to pollute json output
+--   where verbosity = fromFlagOrDefault silent (buildVerbosity (Cabal.buildInfoBuildFlags showBuildInfoFlags ))
 
 buildActionForCommand :: CommandUI BuildFlags
                       -> Verbosity
@@ -482,23 +478,13 @@ buildActionForCommand commandUI verbosity (buildFlags, buildExFlags) extraArgs g
     distPref             <- findSavedDistPref config (buildDistPref buildFlags)
     -- Calls 'configureAction' to do the real work, so nothing special has to be
     -- done to support sandboxes.
-    config'              <- reconfigure configureAction
-                                        verbosity
-                                        distPref
-                                        useSandbox
-                                        noAddSource
-                                        (buildNumJobs buildFlags)
-                                        mempty
-                                        []
-                                        globalFlags
-                                        config
-    nixShell verbosity distPref globalFlags config $ do
-      maybeWithSandboxDirOnSearchPath useSandbox $ buildForCommand commandUI
-                                                                   verbosity
-                                                                   config'
-                                                                   distPref
-                                                                   buildFlags
-                                                                   extraArgs
+    config'              <- reconfigure
+        configureAction verbosity distPref useSandbox noAddSource
+        (buildNumJobs buildFlags) mempty [] globalFlags config
+
+    nixShell verbosity distPref globalFlags config $
+      maybeWithSandboxDirOnSearchPath useSandbox $ buildForCommand
+        commandUI verbosity config' distPref buildFlags extraArgs
 
 -- | Actually do the work of building the package. This is separate from
 -- 'buildAction' so that 'testAction' and 'benchmarkAction' do not invoke
@@ -506,6 +492,7 @@ buildActionForCommand commandUI verbosity (buildFlags, buildExFlags) extraArgs g
 build :: Verbosity -> SavedConfig -> FilePath -> BuildFlags -> [String] -> IO ()
 build = buildForCommand (Cabal.buildCommand defaultProgramDb)
 
+-- | Helper function
 buildForCommand :: CommandUI BuildFlags
                 -> Verbosity
                 -> SavedConfig
@@ -514,12 +501,7 @@ buildForCommand :: CommandUI BuildFlags
                 -> [String]
                 -> IO ()
 buildForCommand command verbosity config distPref buildFlags extraArgs =
-  setupWrapper verbosity
-               setupOptions
-               Nothing
-               command
-               mkBuildFlags
-               (const extraArgs)
+  setupWrapper verbosity setupOptions Nothing command mkBuildFlags (const extraArgs)
  where
   setupOptions = defaultSetupScriptOptions { useDistPref = distPref }
 
@@ -568,8 +550,8 @@ replAction (replFlags, buildExFlags) extraArgs globalFlags = do
       -- be done to support sandboxes.
       _ <-
         reconfigure configureAction
-        verbosity distPref useSandbox noAddSource NoFlag
-        mempty [] globalFlags config
+          verbosity distPref useSandbox noAddSource NoFlag
+          mempty [] globalFlags config
       let progDb = defaultProgramDb
           setupOptions = defaultSetupScriptOptions
             { useCabalVersion = orLaterVersion $ mkVersion [1,18,0]
@@ -1294,23 +1276,3 @@ manpageAction commands flagVerbosity extraArgs _ = do
                  then dropExtension pname
                  else pname
   putStrLn $ manpage cabalCmd commands
-
---Further commands to support ghc-mod usage
-writeAutogenFilesAction :: WriteAutogenFilesFlags -> [String] -> Action
-writeAutogenFilesAction flags _ globalFlags = do
-  let verbosity = fromFlag (wafVerbosity flags)
-  load <- try (loadConfigOrSandboxConfig verbosity globalFlags)
-  let config = either (\(SomeException _) -> mempty) snd load
-  distPref <- findSavedDistPref config (wafDistPref flags)
-  pkg <- fmap LBI.localPkgDescr (getPersistBuildConfig distPref)
-  eLBI <- tryGetPersistBuildConfig distPref
-  case eLBI of
-    Left err -> case err of
-      -- Note: the build config could have been generated by a custom setup
-      -- script built against a different Cabal version, so it's crucial that
-      -- we ignore the bad version error here.
-      ConfigStateFileBadVersion _ _ _ -> pure ()
-      _                               -> die' verbosity (show err)
-    Right lbi -> do
-      initialBuildSteps distPref pkg lbi verbosity
-      pure ()
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/A.cabal b/cabal-testsuite/PackageTests/ShowBuildInfo/A/A.cabal
new file mode 100644
index 00000000000..2873a450394
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/A.cabal
@@ -0,0 +1,32 @@
+cabal-version:       2.4
+-- Initial package description 'A.cabal' generated by 'cabal init'.  For
+-- further documentation, see http://haskell.org/cabal/users-guide/
+
+name:                A
+version:             0.1.0.0
+-- synopsis:
+-- description:
+-- bug-reports:
+license:             BSD-3-Clause
+license-file:        LICENSE
+author:              Foo Bar
+maintainer:          cabal-dev@haskell.org
+-- copyright:
+-- category:
+extra-source-files:  CHANGELOG.md
+
+library
+  exposed-modules:     A
+  -- other-modules:
+  -- other-extensions:
+  build-depends:       base >=4.0.0
+  hs-source-dirs:      src
+  default-language:    Haskell2010
+
+executable A
+  main-is:             Main.hs
+  -- other-modules:
+  -- other-extensions:
+  build-depends:       base >=4.0.0.0
+  hs-source-dirs:      src
+  default-language:    Haskell2010
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/CHANGELOG.md b/cabal-testsuite/PackageTests/ShowBuildInfo/A/CHANGELOG.md
new file mode 100644
index 00000000000..cfa8b563c0e
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/CHANGELOG.md
@@ -0,0 +1,5 @@
+# Revision history for A
+
+## 0.1.0.0 -- YYYY-mm-dd
+
+* First version. Released on an unsuspecting world.
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/LICENSE b/cabal-testsuite/PackageTests/ShowBuildInfo/A/LICENSE
new file mode 100644
index 00000000000..671281e7a8b
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/LICENSE
@@ -0,0 +1,30 @@
+Copyright (c) 2019, Foo Bar
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * Neither the name of Foo Bar nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/Setup.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/A/Setup.hs
new file mode 100644
index 00000000000..9a994af677b
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-exe-exact.out b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-exe-exact.out
new file mode 100644
index 00000000000..6fbda9790b7
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-exe-exact.out
@@ -0,0 +1 @@
+# cabal show-build-info
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-exe-exact.test.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-exe-exact.test.hs
new file mode 100644
index 00000000000..7c8a2be90ea
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-exe-exact.test.hs
@@ -0,0 +1,68 @@
+{-# LANGUAGE DeriveGeneric #-}
+import           Test.Cabal.Prelude
+
+import qualified Data.Text as T
+import qualified Data.Text.Encoding as T
+import           Data.Aeson
+import           GHC.Generics
+
+main = cabalTest $ do
+    r <- cabal' "show-build-info" ["exe:A", "-v0"]
+    let buildInfoEither = eitherDecodeStrict (T.encodeUtf8 . T.pack $ resultOutput r) :: Either String [BuildInfo]
+    case buildInfoEither of
+      Left err -> fail $ "Could not parse build-info command" ++ err
+      Right buildInfos -> do
+        assertEqual "Build Infos, exactly one" 1  (length buildInfos)
+        let [buildInfo] = buildInfos
+        assertEqual "Cabal Version" "3.1.0.0" (cabalVersion buildInfo)
+        assertEqual "Compiler flavour" "ghc" (flavour $ compiler buildInfo)
+        assertBool "Compiler id" (and $ zipWith (==) "ghc" (compilerId $ compiler buildInfo))
+        assertBool "Compiler path non-empty" (not . null . path $ compiler buildInfo)
+        assertEqual "Components, exactly one" 1 (length $ components buildInfo)
+        let [component] = components buildInfo
+        assertEqual "Component type" "exe" (componentType component)
+        assertEqual "Component name" "exe:A" (componentName component)
+        assertEqual "Component unit-id" "A-0.1.0.0-inplace-A" (componentUnitId component)
+        assertBool "Component compiler args are non-empty" (not . null $ componentCompilerArgs component)
+        assertEqual "Component modules" [] (componentModules component)
+        assertEqual "Component source files" ["Main.hs"] (componentSrcFiles component)
+        assertEqual "Component source directories" ["src"] (componentSrcDirs component)
+    return ()
+
+data BuildInfo = BuildInfo
+    { cabalVersion :: String
+    , compiler :: CompilerInfo
+    , components :: [ComponentInfo]
+    } deriving (Generic, Show)
+
+data CompilerInfo = CompilerInfo
+    { flavour :: String
+    , compilerId :: String
+    , path :: String
+    } deriving (Generic, Show)
+
+data ComponentInfo = ComponentInfo
+    { componentType :: String
+    , componentName :: String
+    , componentUnitId :: String
+    , componentCompilerArgs :: [String]
+    , componentModules :: [String]
+    , componentSrcFiles :: [String]
+    , componentSrcDirs :: [String]
+    } deriving (Generic, Show)
+
+instance ToJSON BuildInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON BuildInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+
+instance ToJSON CompilerInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON CompilerInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+instance ToJSON ComponentInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON ComponentInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = drop 10 . camelTo2 '-' }
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact-unit-id-file.out b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact-unit-id-file.out
new file mode 100644
index 00000000000..6fbda9790b7
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact-unit-id-file.out
@@ -0,0 +1 @@
+# cabal show-build-info
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact-unit-id-file.test.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact-unit-id-file.test.hs
new file mode 100644
index 00000000000..abdc7d649f4
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact-unit-id-file.test.hs
@@ -0,0 +1,92 @@
+{-# LANGUAGE DeriveGeneric #-}
+import           Test.Cabal.Prelude
+
+import qualified Data.Text as T
+import qualified Data.Text.Encoding as T
+import           Data.Aeson
+import           GHC.Generics
+
+main = cabalTest $ withSourceCopy $do
+    cwd <- fmap testCurrentDir getTestEnv
+    let fp = cwd </> "unit.json"
+    r <- cabal' "show-build-info" ["--buildinfo-json-output=" ++ fp, "--unit-ids-json=A-0.1.0.0-inplace A-0.1.0.0-inplace-A", "-v0"]
+    shouldExist fp
+    buildInfoEither <- liftIO $ eitherDecodeFileStrict fp
+    case buildInfoEither of
+      Left err -> fail $ "Could not parse build-info command" ++ err
+      Right buildInfos -> do
+        assertEqual "Build Infos, exactly two " 2  (length buildInfos)
+        let [libBuildInfo, exeBuildInfo] = buildInfos
+        assertExe exeBuildInfo
+        assertLib libBuildInfo
+    return ()
+    where
+      assertExe :: BuildInfo -> TestM ()
+      assertExe buildInfo = do
+        assertEqual "Cabal Version" "3.1.0.0" (cabalVersion buildInfo)
+        assertEqual "Compiler flavour" "ghc" (flavour $ compiler buildInfo)
+        assertBool "Compiler id" (and $ zipWith (==) "ghc" (compilerId $ compiler buildInfo))
+        assertBool "Compiler path non-empty" (not . null . path $ compiler buildInfo)
+        assertEqual "Components, exactly one" 1 (length $ components buildInfo)
+        let [component] = components buildInfo
+        assertEqual "Component type" "exe" (componentType component)
+        assertEqual "Component name" "exe:A" (componentName component)
+        assertEqual "Component unit-id" "A-0.1.0.0-inplace-A" (componentUnitId component)
+        assertBool "Component compiler args are non-empty" (not . null $ componentCompilerArgs component)
+        assertEqual "Component modules" [] (componentModules component)
+        assertEqual "Component source files" ["Main.hs"] (componentSrcFiles component)
+        assertEqual "Component source directories" ["src"] (componentSrcDirs component)
+
+      assertLib :: BuildInfo -> TestM ()
+      assertLib buildInfo = do
+        assertEqual "Cabal Version" "3.1.0.0" (cabalVersion buildInfo)
+        assertEqual "Compiler flavour" "ghc" (flavour $ compiler buildInfo)
+        assertBool "Compiler id" (and $ zipWith (==) "ghc" (compilerId $ compiler buildInfo))
+        assertBool "Compiler path non-empty" (not . null . path $ compiler buildInfo)
+        assertEqual "Components, exactly one" 1 (length $ components buildInfo)
+        let [component] = components buildInfo
+        assertEqual "Component type" "lib" (componentType component)
+        assertEqual "Component name" "lib" (componentName component)
+        assertEqual "Component unit-id" "A-0.1.0.0-inplace" (componentUnitId component)
+        assertBool "Component compiler args are non-empty" (not . null $ componentCompilerArgs component)
+        assertEqual "Component modules" ["A"] (componentModules component)
+        assertEqual "Component source files" [] (componentSrcFiles component)
+        assertEqual "Component source directories" ["src"] (componentSrcDirs component)
+
+data BuildInfo = BuildInfo
+    { cabalVersion :: String
+    , compiler :: CompilerInfo
+    , components :: [ComponentInfo]
+    } deriving (Generic, Show)
+
+data CompilerInfo = CompilerInfo
+    { flavour :: String
+    , compilerId :: String
+    , path :: String
+    } deriving (Generic, Show)
+
+data ComponentInfo = ComponentInfo
+    { componentType :: String
+    , componentName :: String
+    , componentUnitId :: String
+    , componentCompilerArgs :: [String]
+    , componentModules :: [String]
+    , componentSrcFiles :: [String]
+    , componentSrcDirs :: [String]
+    } deriving (Generic, Show)
+
+instance ToJSON BuildInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON BuildInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+
+instance ToJSON CompilerInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON CompilerInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+instance ToJSON ComponentInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON ComponentInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = drop 10 . camelTo2 '-' }
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact-unit-id.out b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact-unit-id.out
new file mode 100644
index 00000000000..6fbda9790b7
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact-unit-id.out
@@ -0,0 +1 @@
+# cabal show-build-info
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact-unit-id.test.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact-unit-id.test.hs
new file mode 100644
index 00000000000..63d928bc21c
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact-unit-id.test.hs
@@ -0,0 +1,89 @@
+{-# LANGUAGE DeriveGeneric #-}
+import           Test.Cabal.Prelude
+
+import qualified Data.Text as T
+import qualified Data.Text.Encoding as T
+import           Data.Aeson
+import           GHC.Generics
+
+main = cabalTest $ do
+    r <- cabal' "show-build-info" ["--unit-ids-json=A-0.1.0.0-inplace A-0.1.0.0-inplace-A", "-v0"]
+    let buildInfoEither = eitherDecodeStrict (T.encodeUtf8 . T.pack $ resultOutput r) :: Either String [BuildInfo]
+    case buildInfoEither of
+      Left err -> fail $ "Could not parse build-info command" ++ err
+      Right buildInfos -> do
+        assertEqual "Build Infos, exactly two " 2  (length buildInfos)
+        let [libBuildInfo, exeBuildInfo] = buildInfos
+        assertExe exeBuildInfo
+        assertLib libBuildInfo
+    return ()
+    where
+      assertExe :: BuildInfo -> TestM ()
+      assertExe buildInfo = do
+        assertEqual "Cabal Version" "3.1.0.0" (cabalVersion buildInfo)
+        assertEqual "Compiler flavour" "ghc" (flavour $ compiler buildInfo)
+        assertBool "Compiler id" (and $ zipWith (==) "ghc" (compilerId $ compiler buildInfo))
+        assertBool "Compiler path non-empty" (not . null . path $ compiler buildInfo)
+        assertEqual "Components, exactly one" 1 (length $ components buildInfo)
+        let [component] = components buildInfo
+        assertEqual "Component type" "exe" (componentType component)
+        assertEqual "Component name" "exe:A" (componentName component)
+        assertEqual "Component unit-id" "A-0.1.0.0-inplace-A" (componentUnitId component)
+        assertBool "Component compiler args are non-empty" (not . null $ componentCompilerArgs component)
+        assertEqual "Component modules" [] (componentModules component)
+        assertEqual "Component source files" ["Main.hs"] (componentSrcFiles component)
+        assertEqual "Component source directories" ["src"] (componentSrcDirs component)
+
+      assertLib :: BuildInfo -> TestM ()
+      assertLib buildInfo = do
+        assertEqual "Cabal Version" "3.1.0.0" (cabalVersion buildInfo)
+        assertEqual "Compiler flavour" "ghc" (flavour $ compiler buildInfo)
+        assertBool "Compiler id" (and $ zipWith (==) "ghc" (compilerId $ compiler buildInfo))
+        assertBool "Compiler path non-empty" (not . null . path $ compiler buildInfo)
+        assertEqual "Components, exactly one" 1 (length $ components buildInfo)
+        let [component] = components buildInfo
+        assertEqual "Component type" "lib" (componentType component)
+        assertEqual "Component name" "lib" (componentName component)
+        assertEqual "Component unit-id" "A-0.1.0.0-inplace" (componentUnitId component)
+        assertBool "Component compiler args are non-empty" (not . null $ componentCompilerArgs component)
+        assertEqual "Component modules" ["A"] (componentModules component)
+        assertEqual "Component source files" [] (componentSrcFiles component)
+        assertEqual "Component source directories" ["src"] (componentSrcDirs component)
+
+data BuildInfo = BuildInfo
+    { cabalVersion :: String
+    , compiler :: CompilerInfo
+    , components :: [ComponentInfo]
+    } deriving (Generic, Show)
+
+data CompilerInfo = CompilerInfo
+    { flavour :: String
+    , compilerId :: String
+    , path :: String
+    } deriving (Generic, Show)
+
+data ComponentInfo = ComponentInfo
+    { componentType :: String
+    , componentName :: String
+    , componentUnitId :: String
+    , componentCompilerArgs :: [String]
+    , componentModules :: [String]
+    , componentSrcFiles :: [String]
+    , componentSrcDirs :: [String]
+    } deriving (Generic, Show)
+
+instance ToJSON BuildInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON BuildInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+
+instance ToJSON CompilerInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON CompilerInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+instance ToJSON ComponentInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON ComponentInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = drop 10 . camelTo2 '-' }
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact.out b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact.out
new file mode 100644
index 00000000000..6fbda9790b7
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact.out
@@ -0,0 +1 @@
+# cabal show-build-info
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact.test.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact.test.hs
new file mode 100644
index 00000000000..14b523e3992
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-multiple-exact.test.hs
@@ -0,0 +1,89 @@
+{-# LANGUAGE DeriveGeneric #-}
+import           Test.Cabal.Prelude
+
+import qualified Data.Text as T
+import qualified Data.Text.Encoding as T
+import           Data.Aeson
+import           GHC.Generics
+
+main = cabalTest $ do
+    r <- cabal' "show-build-info" ["exe:A", "lib:A", "-v0"]
+    let buildInfoEither = eitherDecodeStrict (T.encodeUtf8 . T.pack $ resultOutput r) :: Either String [BuildInfo]
+    case buildInfoEither of
+      Left err -> fail $ "Could not parse build-info command" ++ err
+      Right buildInfos -> do
+        assertEqual "Build Infos, exactly two " 2  (length buildInfos)
+        let [libBuildInfo, exeBuildInfo] = buildInfos
+        assertExe exeBuildInfo
+        assertLib libBuildInfo
+    return ()
+    where
+      assertExe :: BuildInfo -> TestM ()
+      assertExe buildInfo = do
+        assertEqual "Cabal Version" "3.1.0.0" (cabalVersion buildInfo)
+        assertEqual "Compiler flavour" "ghc" (flavour $ compiler buildInfo)
+        assertBool "Compiler id" (and $ zipWith (==) "ghc" (compilerId $ compiler buildInfo))
+        assertBool "Compiler path non-empty" (not . null . path $ compiler buildInfo)
+        assertEqual "Components, exactly one" 1 (length $ components buildInfo)
+        let [component] = components buildInfo
+        assertEqual "Component type" "exe" (componentType component)
+        assertEqual "Component name" "exe:A" (componentName component)
+        assertEqual "Component unit-id" "A-0.1.0.0-inplace-A" (componentUnitId component)
+        assertBool "Component compiler args are non-empty" (not . null $ componentCompilerArgs component)
+        assertEqual "Component modules" [] (componentModules component)
+        assertEqual "Component source files" ["Main.hs"] (componentSrcFiles component)
+        assertEqual "Component source directories" ["src"] (componentSrcDirs component)
+
+      assertLib :: BuildInfo -> TestM ()
+      assertLib buildInfo = do
+        assertEqual "Cabal Version" "3.1.0.0" (cabalVersion buildInfo)
+        assertEqual "Compiler flavour" "ghc" (flavour $ compiler buildInfo)
+        assertBool "Compiler id" (and $ zipWith (==) "ghc" (compilerId $ compiler buildInfo))
+        assertBool "Compiler path non-empty" (not . null . path $ compiler buildInfo)
+        assertEqual "Components, exactly one" 1 (length $ components buildInfo)
+        let [component] = components buildInfo
+        assertEqual "Component type" "lib" (componentType component)
+        assertEqual "Component name" "lib" (componentName component)
+        assertEqual "Component unit-id" "A-0.1.0.0-inplace" (componentUnitId component)
+        assertBool "Component compiler args are non-empty" (not . null $ componentCompilerArgs component)
+        assertEqual "Component modules" ["A"] (componentModules component)
+        assertEqual "Component source files" [] (componentSrcFiles component)
+        assertEqual "Component source directories" ["src"] (componentSrcDirs component)
+
+data BuildInfo = BuildInfo
+    { cabalVersion :: String
+    , compiler :: CompilerInfo
+    , components :: [ComponentInfo]
+    } deriving (Generic, Show)
+
+data CompilerInfo = CompilerInfo
+    { flavour :: String
+    , compilerId :: String
+    , path :: String
+    } deriving (Generic, Show)
+
+data ComponentInfo = ComponentInfo
+    { componentType :: String
+    , componentName :: String
+    , componentUnitId :: String
+    , componentCompilerArgs :: [String]
+    , componentModules :: [String]
+    , componentSrcFiles :: [String]
+    , componentSrcDirs :: [String]
+    } deriving (Generic, Show)
+
+instance ToJSON BuildInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON BuildInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+
+instance ToJSON CompilerInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON CompilerInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+instance ToJSON ComponentInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON ComponentInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = drop 10 . camelTo2 '-' }
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-unknown.out b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-unknown.out
new file mode 100644
index 00000000000..5f6512b4dc9
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-unknown.out
@@ -0,0 +1,12 @@
+# cabal show-build-info
+cabal: Internal error in target matching. It should always be possible to find a syntax that's sufficiently qualified to give an unambiguous match. However when matching 'exe:B'  we found exe:B (unknown-component) which does not have an unambiguous syntax. The possible syntax and the targets they match are as follows:
+'exe:B' which matches exe:B (unknown-component), :pkg:exe:lib:exe:module:B (unknown-module), :pkg:exe:lib:exe:file:B (unknown-file)
+# cabal show-build-info
+Resolving dependencies...
+cabal: No unit B-inplace-0.1.0.0
+# cabal show-build-info
+Configuring library for A-0.1.0.0..
+cabal: No unit B-inplace-0.1.0.0
+# cabal show-build-info
+cabal: Internal error in target matching. It should always be possible to find a syntax that's sufficiently qualified to give an unambiguous match. However when matching 'exe:B'  we found exe:B (unknown-component) which does not have an unambiguous syntax. The possible syntax and the targets they match are as follows:
+'exe:B' which matches exe:B (unknown-component), :pkg:exe:lib:exe:module:B (unknown-module), :pkg:exe:lib:exe:file:B (unknown-file)
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-unknown.test.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-unknown.test.hs
new file mode 100644
index 00000000000..b07607b3779
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/build-info-unknown.test.hs
@@ -0,0 +1,14 @@
+import           Test.Cabal.Prelude
+
+main = cabalTest $ do
+    r <- fails $ cabal' "show-build-info" ["exe:B"]
+    assertOutputContains "Internal error in target matching." r
+
+    r <- fails $ cabal' "show-build-info" ["--unit-ids-json=B-inplace-0.1.0.0"]
+    assertOutputContains "No unit B-inplace-0.1.0.0" r
+
+    r <- fails $ cabal' "show-build-info" ["--unit-ids-json=A-0.1.0.0-inplace B-inplace-0.1.0.0"]
+    assertOutputContains "No unit B-inplace-0.1.0.0" r
+
+    r <- fails $ cabal' "show-build-info" ["--unit-ids-json=A-0.1.0.0-inplace", "exe:B"]
+    assertOutputContains "Internal error in target matching." r
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/cabal.project b/cabal-testsuite/PackageTests/ShowBuildInfo/A/cabal.project
new file mode 100644
index 00000000000..5356e76f67c
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/cabal.project
@@ -0,0 +1 @@
+packages: .
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/src/A.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/A/src/A.hs
new file mode 100644
index 00000000000..ad7a0c07729
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/src/A.hs
@@ -0,0 +1,4 @@
+module A where
+
+foo :: Int -> Int
+foo = id
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/A/src/Main.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/A/src/Main.hs
new file mode 100644
index 00000000000..65ae4a05d5d
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/A/src/Main.hs
@@ -0,0 +1,4 @@
+module Main where
+
+main :: IO ()
+main = putStrLn "Hello, Haskell!"
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/B/B.cabal b/cabal-testsuite/PackageTests/ShowBuildInfo/B/B.cabal
new file mode 100644
index 00000000000..d8ed91d655b
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/B/B.cabal
@@ -0,0 +1,24 @@
+cabal-version:       2.4
+-- Initial package description 'B.cabal' generated by 'cabal init'.  For
+-- further documentation, see http://haskell.org/cabal/users-guide/
+
+name:                B
+version:             0.1.0.0
+-- synopsis:
+-- description:
+-- bug-reports:
+license:             BSD-3-Clause
+license-file:        LICENSE
+author:              Foo Bar
+maintainer:          cabal-dev@haskell.org
+-- copyright:
+-- category:
+extra-source-files:  CHANGELOG.md
+
+library
+  exposed-modules:     A
+  -- other-modules:
+  -- other-extensions:
+  build-depends:       base >=4.0.0.0
+  hs-source-dirs:      src
+  default-language:    Haskell2010
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/B/CHANGELOG.md b/cabal-testsuite/PackageTests/ShowBuildInfo/B/CHANGELOG.md
new file mode 100644
index 00000000000..5cf6ac2adb2
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/B/CHANGELOG.md
@@ -0,0 +1,5 @@
+# Revision history for B
+
+## 0.1.0.0 -- YYYY-mm-dd
+
+* First version. Released on an unsuspecting world.
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/B/LICENSE b/cabal-testsuite/PackageTests/ShowBuildInfo/B/LICENSE
new file mode 100644
index 00000000000..671281e7a8b
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/B/LICENSE
@@ -0,0 +1,30 @@
+Copyright (c) 2019, Foo Bar
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * Neither the name of Foo Bar nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/B/Setup.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/B/Setup.hs
new file mode 100644
index 00000000000..9a994af677b
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/B/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/B/build-info-lib-exact.out b/cabal-testsuite/PackageTests/ShowBuildInfo/B/build-info-lib-exact.out
new file mode 100644
index 00000000000..6fbda9790b7
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/B/build-info-lib-exact.out
@@ -0,0 +1 @@
+# cabal show-build-info
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/B/build-info-lib-exact.test.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/B/build-info-lib-exact.test.hs
new file mode 100644
index 00000000000..c09a36a274f
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/B/build-info-lib-exact.test.hs
@@ -0,0 +1,68 @@
+{-# LANGUAGE DeriveGeneric #-}
+import           Test.Cabal.Prelude
+
+import qualified Data.Text as T
+import qualified Data.Text.Encoding as T
+import           Data.Aeson
+import           GHC.Generics
+
+main = cabalTest $ do
+    r <- cabal' "show-build-info" ["lib:B", "-v0"]
+    let buildInfoEither = eitherDecodeStrict (T.encodeUtf8 . T.pack $ resultOutput r) :: Either String [BuildInfo]
+    case buildInfoEither of
+      Left err -> fail $ "Could not parse build-info command" ++ err
+      Right buildInfos -> do
+        assertEqual "Build Infos, exactly one" 1  (length buildInfos)
+        let [buildInfo] = buildInfos
+        assertEqual "Cabal Version" "3.1.0.0" (cabalVersion buildInfo)
+        assertEqual "Compiler flavour" "ghc" (flavour $ compiler buildInfo)
+        assertBool "Compiler id" (and $ zipWith (==) "ghc" (compilerId $ compiler buildInfo))
+        assertBool "Compiler path non-empty" (not . null . path $ compiler buildInfo)
+        assertEqual "Components, exactly one" 1 (length $ components buildInfo)
+        let [component] = components buildInfo
+        assertEqual "Component type" "lib" (componentType component)
+        assertEqual "Component name" "lib" (componentName component)
+        assertEqual "Component unit-id" "B-0.1.0.0-inplace" (componentUnitId component)
+        assertBool "Component compiler args are non-empty" (not . null $ componentCompilerArgs component)
+        assertEqual "Component modules" ["A"] (componentModules component)
+        assertEqual "Component source files" [] (componentSrcFiles component)
+        assertEqual "Component source directories" ["src"] (componentSrcDirs component)
+    return ()
+
+data BuildInfo = BuildInfo
+    { cabalVersion :: String
+    , compiler :: CompilerInfo
+    , components :: [ComponentInfo]
+    } deriving (Generic, Show)
+
+data CompilerInfo = CompilerInfo
+    { flavour :: String
+    , compilerId :: String
+    , path :: String
+    } deriving (Generic, Show)
+
+data ComponentInfo = ComponentInfo
+    { componentType :: String
+    , componentName :: String
+    , componentUnitId :: String
+    , componentCompilerArgs :: [String]
+    , componentModules :: [String]
+    , componentSrcFiles :: [String]
+    , componentSrcDirs :: [String]
+    } deriving (Generic, Show)
+
+instance ToJSON BuildInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON BuildInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+
+instance ToJSON CompilerInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON CompilerInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+instance ToJSON ComponentInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON ComponentInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = drop 10 . camelTo2 '-' }
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/B/cabal.project b/cabal-testsuite/PackageTests/ShowBuildInfo/B/cabal.project
new file mode 100644
index 00000000000..e6fdbadb439
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/B/cabal.project
@@ -0,0 +1 @@
+packages: .
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/B/src/A.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/B/src/A.hs
new file mode 100644
index 00000000000..ad7a0c07729
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/B/src/A.hs
@@ -0,0 +1,4 @@
+module A where
+
+foo :: Int -> Int
+foo = id
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/CHANGELOG.md b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/CHANGELOG.md
new file mode 100644
index 00000000000..624468cdfdb
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/CHANGELOG.md
@@ -0,0 +1,5 @@
+# Revision history for Complex
+
+## 0.1.0.0 -- YYYY-mm-dd
+
+* First version. Released on an unsuspecting world.
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/Complex.cabal b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/Complex.cabal
new file mode 100644
index 00000000000..9047830cd4f
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/Complex.cabal
@@ -0,0 +1,54 @@
+cabal-version:       2.4
+name:                Complex
+version:             0.1.0.0
+license:             MIT
+license-file:        LICENSE
+author:              Bla Bla
+maintainer:          ""
+category:            Testing
+extra-source-files:  CHANGELOG.md
+
+
+library
+  build-depends:       base
+  hs-source-dirs:      src
+  default-language:    Haskell2010
+  exposed-modules:     Lib
+  other-modules:       Paths_complex
+
+  ghc-options:         -threaded -rtsopts -with-rtsopts=-N -Wall
+
+executable Complex
+  main-is:             Main.lhs
+  build-depends:       base
+  hs-source-dirs:      src
+  default-language:    Haskell2010
+  other-modules:       Paths_complex
+  ghc-options:         -threaded -rtsopts -with-rtsopts=-N -Wredundant-constraints
+                       -with-rtsopts=-T
+
+test-suite unit-test
+  type:                exitcode-stdio-1.0
+  hs-source-dirs:      test
+  build-depends:       hspec
+  main-is:             Main.hs
+
+test-suite func-test
+  type:                exitcode-stdio-1.0
+  hs-source-dirs:      test
+  build-depends:       hspec
+  main-is:             Main.hs
+
+benchmark complex-benchmarks
+  type: exitcode-stdio-1.0
+  main-is: Main.hs
+  other-modules:
+      Paths_complex
+  hs-source-dirs:
+      benchmark
+  ghc-options: -Wall -rtsopts -threaded -with-rtsopts=-N
+  build-depends:
+      base
+    , criterion
+    , Complex
+  default-language: Haskell2010
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/LICENSE b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/LICENSE
new file mode 100644
index 00000000000..a234fc7e8dd
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/LICENSE
@@ -0,0 +1,20 @@
+Copyright (c) 2019 Bla Bla
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be included
+in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/Setup.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/Setup.hs
new file mode 100644
index 00000000000..9a994af677b
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/cabal.project b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/cabal.project
new file mode 100644
index 00000000000..5356e76f67c
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/cabal.project
@@ -0,0 +1 @@
+packages: .
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/exe.out b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/exe.out
new file mode 100644
index 00000000000..6fbda9790b7
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/exe.out
@@ -0,0 +1 @@
+# cabal show-build-info
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/exe.test.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/exe.test.hs
new file mode 100644
index 00000000000..e56a02600ff
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/exe.test.hs
@@ -0,0 +1,84 @@
+{-# LANGUAGE DeriveGeneric #-}
+import           Test.Cabal.Prelude
+
+import qualified Data.Text as T
+import qualified Data.Text.Encoding as T
+import           Data.Aeson
+import           GHC.Generics
+
+main = cabalTest $ do
+  r <- cabal' "show-build-info" ["exe:Complex", "-v0"]
+  let buildInfoEither = eitherDecodeStrict (T.encodeUtf8 . T.pack $ resultOutput r) :: Either String [BuildInfo]
+  case buildInfoEither of
+    Left err -> fail $ "Could not parse build-info command" ++ err
+    Right buildInfos -> do
+      assertEqual "Build Infos, exactly one" 1  (length buildInfos)
+      let [buildInfo] = buildInfos
+      assertEqual "Cabal Version" "3.1.0.0" (cabalVersion buildInfo)
+      assertEqual "Compiler flavour" "ghc" (flavour $ compiler buildInfo)
+      assertBool "Compiler id" (and $ zipWith (==) "ghc" (compilerId $ compiler buildInfo))
+      assertBool "Compiler path non-empty" (not . null . path $ compiler buildInfo)
+      assertEqual "Components, exactly one" 1 (length $ components buildInfo)
+      let [component] = components buildInfo
+      assertEqual "Component type" "exe" (componentType component)
+      assertEqual "Component name" "exe:Complex" (componentName component)
+      assertEqual "Component unit-id" "Complex-0.1.0.0-inplace-Complex" (componentUnitId component)
+      assertBool "Component compiler args are non-empty" (not . null $ componentCompilerArgs component)
+      assertBool "Component ghc-options contains all specified in .cabal"
+                    (all
+                      (`elem` componentCompilerArgs component)
+                      [ "-threaded"
+                      , "-rtsopts"
+                      , "-with-rtsopts=-N"
+                      , "-with-rtsopts=-T"
+                      , "-Wredundant-constraints"
+                      ]
+                    )
+      assertBool "Component ghc-options does not contain -Wall"
+                    (all
+                      (`notElem` componentCompilerArgs component)
+                      [ "-Wall"
+                      ]
+                    )
+      assertEqual "Component modules" ["Paths_complex"] (componentModules component)
+      assertEqual "Component source files" ["Main.lhs"] (componentSrcFiles component)
+      assertEqual "Component source directories" ["src"] (componentSrcDirs component)
+  return ()
+
+data BuildInfo = BuildInfo
+    { cabalVersion :: String
+    , compiler :: CompilerInfo
+    , components :: [ComponentInfo]
+    } deriving (Generic, Show)
+
+data CompilerInfo = CompilerInfo
+    { flavour :: String
+    , compilerId :: String
+    , path :: String
+    } deriving (Generic, Show)
+
+data ComponentInfo = ComponentInfo
+    { componentType :: String
+    , componentName :: String
+    , componentUnitId :: String
+    , componentCompilerArgs :: [String]
+    , componentModules :: [String]
+    , componentSrcFiles :: [String]
+    , componentSrcDirs :: [String]
+    } deriving (Generic, Show)
+
+instance ToJSON BuildInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON BuildInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+
+instance ToJSON CompilerInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON CompilerInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+instance ToJSON ComponentInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON ComponentInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = drop 10 . camelTo2 '-' }
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/lib.out b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/lib.out
new file mode 100644
index 00000000000..6fbda9790b7
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/lib.out
@@ -0,0 +1 @@
+# cabal show-build-info
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/lib.test.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/lib.test.hs
new file mode 100644
index 00000000000..d119eb633d9
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/lib.test.hs
@@ -0,0 +1,83 @@
+{-# LANGUAGE DeriveGeneric #-}
+import           Test.Cabal.Prelude
+
+import qualified Data.Text as T
+import qualified Data.Text.Encoding as T
+import           Data.Aeson
+import           GHC.Generics
+
+main = cabalTest $ do
+    r <- cabal' "show-build-info" ["lib:Complex", "-v0"]
+    let buildInfoEither = eitherDecodeStrict (T.encodeUtf8 . T.pack $ resultOutput r) :: Either String [BuildInfo]
+    case buildInfoEither of
+      Left err -> fail $ "Could not parse build-info command" ++ err
+      Right buildInfos -> do
+        assertEqual "Build Infos, exactly one" 1  (length buildInfos)
+        let [buildInfo] = buildInfos
+        assertEqual "Cabal Version" "3.1.0.0" (cabalVersion buildInfo)
+        assertEqual "Compiler flavour" "ghc" (flavour $ compiler buildInfo)
+        assertBool "Compiler id" (and $ zipWith (==) "ghc" (compilerId $ compiler buildInfo))
+        assertBool "Compiler path non-empty" (not . null . path $ compiler buildInfo)
+        assertEqual "Components, exactly one" 1 (length $ components buildInfo)
+        let [component] = components buildInfo
+        assertEqual "Component type" "lib" (componentType component)
+        assertEqual "Component name" "lib" (componentName component)
+        assertEqual "Component unit-id" "Complex-0.1.0.0-inplace" (componentUnitId component)
+        assertBool "Component compiler args are non-empty" (not . null $ componentCompilerArgs component)
+        assertBool "Component ghc-options contains all specified in .cabal"
+                  (all
+                    (`elem` componentCompilerArgs component)
+                    [ "-threaded"
+                    , "-rtsopts"
+                    , "-with-rtsopts=-N"
+                    , "-Wall"
+                    ]
+                  )
+        assertBool "Component ghc-options does not contain -Wredundant-constraints"
+                  (all
+                    (`notElem` componentCompilerArgs component)
+                    [ "-Wredundant-constraints"
+                    ]
+                  )
+        assertEqual "Component modules" ["Lib", "Paths_complex"] (componentModules component)
+        assertEqual "Component source files" [] (componentSrcFiles component)
+        assertEqual "Component source directories" ["src"] (componentSrcDirs component)
+    return ()
+
+data BuildInfo = BuildInfo
+    { cabalVersion :: String
+    , compiler :: CompilerInfo
+    , components :: [ComponentInfo]
+    } deriving (Generic, Show)
+
+data CompilerInfo = CompilerInfo
+    { flavour :: String
+    , compilerId :: String
+    , path :: String
+    } deriving (Generic, Show)
+
+data ComponentInfo = ComponentInfo
+    { componentType :: String
+    , componentName :: String
+    , componentUnitId :: String
+    , componentCompilerArgs :: [String]
+    , componentModules :: [String]
+    , componentSrcFiles :: [String]
+    , componentSrcDirs :: [String]
+    } deriving (Generic, Show)
+
+instance ToJSON BuildInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON BuildInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+
+instance ToJSON CompilerInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON CompilerInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = camelTo2 '-' }
+
+instance ToJSON ComponentInfo where
+  toEncoding = genericToEncoding defaultOptions
+instance FromJSON ComponentInfo where
+  parseJSON = genericParseJSON defaultOptions { fieldLabelModifier = drop 10 . camelTo2 '-' }
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/src/Lib.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/src/Lib.hs
new file mode 100644
index 00000000000..5d35e3e9617
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/src/Lib.hs
@@ -0,0 +1,4 @@
+module Lib where
+
+foo :: Int -> Int
+foo = (+1)
\ No newline at end of file
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/src/Main.lhs b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/src/Main.lhs
new file mode 100644
index 00000000000..a1b75006b8d
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/src/Main.lhs
@@ -0,0 +1,9 @@
+module Main where
+
+import Lib
+
+main :: IO ()
+main = do
+    let i = foo 5
+    putStrLn "Hello, Haskell!"
+    print i
diff --git a/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/test/Main.hs b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/test/Main.hs
new file mode 100644
index 00000000000..3ef47688534
--- /dev/null
+++ b/cabal-testsuite/PackageTests/ShowBuildInfo/Complex/test/Main.hs
@@ -0,0 +1 @@
+main = return ()
\ No newline at end of file