diff --git a/pkgs/sagemath-categories/pyproject.toml.m4 b/pkgs/sagemath-categories/pyproject.toml.m4
index eed48a1db15..edbafa59242 100644
--- a/pkgs/sagemath-categories/pyproject.toml.m4
+++ b/pkgs/sagemath-categories/pyproject.toml.m4
@@ -37,3 +37,20 @@ include-package-data = false
 
 [tool.setuptools.dynamic]
 version = {file = ["VERSION.txt"]}
+
+[external]
+# External dependencies in the format proposed by https://peps.python.org/pep-0725
+build-requires = [
+  "virtual:compiler/c",
+  "virtual:compiler/cpp",
+  "pkg:generic/pkg-config",
+]
+
+host-requires = [
+  "pkg:generic/gmp",
+  "pkg:generic/mpc",
+  "pkg:generic/mpfr",
+]
+
+dependencies = [
+]
diff --git a/pkgs/sagemath-objects/pyproject.toml.m4 b/pkgs/sagemath-objects/pyproject.toml.m4
index a8d7d83a44a..68cfbafe935 100644
--- a/pkgs/sagemath-objects/pyproject.toml.m4
+++ b/pkgs/sagemath-objects/pyproject.toml.m4
@@ -46,3 +46,20 @@ version = {file = ["VERSION.txt"]}
     "python_debug.h",
 ]
 "sage.rings" = ["integer_fake.h"]
+
+[external]
+# External dependencies in the format proposed by https://peps.python.org/pep-0725
+build-requires = [
+  "virtual:compiler/c",
+  "virtual:compiler/cpp",
+  "pkg:generic/pkg-config",
+]
+
+host-requires = [
+  "pkg:generic/gmp",
+  "pkg:generic/mpc",
+  "pkg:generic/mpfr",
+]
+
+dependencies = [
+]