diff --git a/sci-mathematics/lean/lean-3.43.0.ebuild b/sci-mathematics/lean/lean-3.43.0.ebuild
index 5d8ee8eecd4b8..6623228581a06 100644
--- a/sci-mathematics/lean/lean-3.43.0.ebuild
+++ b/sci-mathematics/lean/lean-3.43.0.ebuild
@@ -6,7 +6,7 @@ EAPI=8
 MAJOR=$(ver_cut 1)
 CMAKE_IN_SOURCE_BUILD="ON"
 
-inherit cmake readme.gentoo-r1
+inherit flag-o-matic cmake readme.gentoo-r1
 
 DESCRIPTION="The Lean Theorem Prover"
 HOMEPAGE="https://leanprover-community.github.io/"
@@ -37,6 +37,8 @@ src_configure() {
 		CMAKE_BUILD_TYPE="Release"
 	fi
 
+	filter-lto
+
 	local mycmakeargs=(
 		-DALPHA=ON
 		-DAUTO_THREAD_FINALIZATION=ON
diff --git a/sci-mathematics/lean/lean-3.44.1.ebuild b/sci-mathematics/lean/lean-3.44.1.ebuild
index 5d8ee8eecd4b8..6623228581a06 100644
--- a/sci-mathematics/lean/lean-3.44.1.ebuild
+++ b/sci-mathematics/lean/lean-3.44.1.ebuild
@@ -6,7 +6,7 @@ EAPI=8
 MAJOR=$(ver_cut 1)
 CMAKE_IN_SOURCE_BUILD="ON"
 
-inherit cmake readme.gentoo-r1
+inherit flag-o-matic cmake readme.gentoo-r1
 
 DESCRIPTION="The Lean Theorem Prover"
 HOMEPAGE="https://leanprover-community.github.io/"
@@ -37,6 +37,8 @@ src_configure() {
 		CMAKE_BUILD_TYPE="Release"
 	fi
 
+	filter-lto
+
 	local mycmakeargs=(
 		-DALPHA=ON
 		-DAUTO_THREAD_FINALIZATION=ON
diff --git a/sci-mathematics/lean/lean-3.45.0.ebuild b/sci-mathematics/lean/lean-3.45.0.ebuild
index 5d8ee8eecd4b8..6623228581a06 100644
--- a/sci-mathematics/lean/lean-3.45.0.ebuild
+++ b/sci-mathematics/lean/lean-3.45.0.ebuild
@@ -6,7 +6,7 @@ EAPI=8
 MAJOR=$(ver_cut 1)
 CMAKE_IN_SOURCE_BUILD="ON"
 
-inherit cmake readme.gentoo-r1
+inherit flag-o-matic cmake readme.gentoo-r1
 
 DESCRIPTION="The Lean Theorem Prover"
 HOMEPAGE="https://leanprover-community.github.io/"
@@ -37,6 +37,8 @@ src_configure() {
 		CMAKE_BUILD_TYPE="Release"
 	fi
 
+	filter-lto
+
 	local mycmakeargs=(
 		-DALPHA=ON
 		-DAUTO_THREAD_FINALIZATION=ON
diff --git a/sci-mathematics/lean/lean-3.9999.ebuild b/sci-mathematics/lean/lean-3.9999.ebuild
index 5d8ee8eecd4b8..6623228581a06 100644
--- a/sci-mathematics/lean/lean-3.9999.ebuild
+++ b/sci-mathematics/lean/lean-3.9999.ebuild
@@ -6,7 +6,7 @@ EAPI=8
 MAJOR=$(ver_cut 1)
 CMAKE_IN_SOURCE_BUILD="ON"
 
-inherit cmake readme.gentoo-r1
+inherit flag-o-matic cmake readme.gentoo-r1
 
 DESCRIPTION="The Lean Theorem Prover"
 HOMEPAGE="https://leanprover-community.github.io/"
@@ -37,6 +37,8 @@ src_configure() {
 		CMAKE_BUILD_TYPE="Release"
 	fi
 
+	filter-lto
+
 	local mycmakeargs=(
 		-DALPHA=ON
 		-DAUTO_THREAD_FINALIZATION=ON