diff --git a/ports/unix/variants/coverage/manifest.py b/ports/unix/variants/coverage/manifest.py
index 556d445d75..37f2531a84 100644
--- a/ports/unix/variants/coverage/manifest.py
+++ b/ports/unix/variants/coverage/manifest.py
@@ -1,3 +1,4 @@
+add_library("unix-ffi", "$(MPY_LIB_DIR)/unix-ffi")
 freeze_as_str("frzstr")
 freeze_as_mpy("frzmpy")
 freeze_mpy("$(MPY_DIR)/tests/frozen")
diff --git a/ports/unix/variants/manifest.py b/ports/unix/variants/manifest.py
index 88cc1ad8e5..649b1e4c46 100644
--- a/ports/unix/variants/manifest.py
+++ b/ports/unix/variants/manifest.py
@@ -1,2 +1,3 @@
+add_library("unix-ffi", "$(MPY_LIB_DIR)/unix-ffi")
 require("mip-cmdline")
 require("ssl")