diff --git a/cabal-install/src/Distribution/Client/CmdBuild.hs b/cabal-install/src/Distribution/Client/CmdBuild.hs
index e3b1f4459a8..3f2c7589c9a 100644
--- a/cabal-install/src/Distribution/Client/CmdBuild.hs
+++ b/cabal-install/src/Distribution/Client/CmdBuild.hs
@@ -6,6 +6,9 @@ module Distribution.Client.CmdBuild (
     buildCommand,
     buildAction,
 
+    BuildFlags(..),
+    defaultBuildFlags,
+
     -- * Internals exposed for testing
     selectPackageTargets,
     selectComponentTarget
diff --git a/cabal-install/src/Distribution/Client/CmdHaddock.hs b/cabal-install/src/Distribution/Client/CmdHaddock.hs
index 32881099073..4b5727628f2 100644
--- a/cabal-install/src/Distribution/Client/CmdHaddock.hs
+++ b/cabal-install/src/Distribution/Client/CmdHaddock.hs
@@ -7,6 +7,8 @@ module Distribution.Client.CmdHaddock (
     haddockCommand,
     haddockAction,
 
+    ClientHaddockFlags(..),
+
     -- * Internals exposed for testing
     selectPackageTargets,
     selectComponentTarget
diff --git a/changelog.d/issue-8351 b/changelog.d/issue-8351
new file mode 100644
index 00000000000..59101a589fc
--- /dev/null
+++ b/changelog.d/issue-8351
@@ -0,0 +1,11 @@
+synopsis: Expose BuildFlags and ClientHaddockFlags
+packages: cabal-install
+prs: #8353
+issues: #8351
+
+description: {
+
+Some types are present in public functions in cabal-install, but they are not exported.
+This PR fix it for BuildFlags and ClientHaddockFlags.
+
+}
\ No newline at end of file