From b7b1dcbc3da0aa433c4fe6bc350f542963eadc6d Mon Sep 17 00:00:00 2001
From: Your Name <you@example.com>
Date: Sun, 30 Nov 2025 23:55:37 +0000
Subject: [PATCH 1/2] faiss: optional C API and shared library

---
 pkgs/by-name/fa/faiss/package.nix | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pkgs/by-name/fa/faiss/package.nix b/pkgs/by-name/fa/faiss/package.nix
index f7429b62c479..4935c97199e2 100644
--- a/pkgs/by-name/fa/faiss/package.nix
+++ b/pkgs/by-name/fa/faiss/package.nix
@@ -3,11 +3,13 @@
   config,
   fetchFromGitHub,
   stdenv,
+  capiSupport ? false,
   cmake,
   cudaPackages ? { },
   cudaSupport ? config.cudaSupport,
   pythonSupport ? true,
   python3Packages,
+  sharedLibrarySupport ? false,
   llvmPackages,
   blas,
   swig,
@@ -73,6 +75,8 @@ stdenv.mkDerivation (finalAttrs: {
   ++ lib.optionals cudaSupport cudaComponents;
 
   cmakeFlags = [
+    (lib.cmakeBool "BUILD_SHARED_LIBS" sharedLibrarySupport)
+    (lib.cmakeBool "FAISS_ENABLE_C_API" capiSupport)
     (lib.cmakeBool "FAISS_ENABLE_GPU" cudaSupport)
     (lib.cmakeBool "FAISS_ENABLE_PYTHON" pythonSupport)
     (lib.cmakeFeature "FAISS_OPT_LEVEL" optLevel)

From 3cf6067b8662b7fec2857279593f494058af00b6 Mon Sep 17 00:00:00 2001
From: Your Name <you@example.com>
Date: Tue, 9 Dec 2025 07:03:32 +0000
Subject: [PATCH 2/2] faiss: enable C API by default

---
 pkgs/by-name/fa/faiss/package.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkgs/by-name/fa/faiss/package.nix b/pkgs/by-name/fa/faiss/package.nix
index 4935c97199e2..68def4f27cfb 100644
--- a/pkgs/by-name/fa/faiss/package.nix
+++ b/pkgs/by-name/fa/faiss/package.nix
@@ -3,7 +3,7 @@
   config,
   fetchFromGitHub,
   stdenv,
-  capiSupport ? false,
+  capiSupport ? true,
   cmake,
   cudaPackages ? { },
   cudaSupport ? config.cudaSupport,