diff --git a/druntime/def/Makefile b/druntime/def/Makefile
new file mode 100644
index 0000000000..a876ca7a11
--- /dev/null
+++ b/druntime/def/Makefile
@@ -0,0 +1,8 @@
+LIBS:=glu32 odbc32 opengl32 rpcrt4 shell32 version wininet winspool
+
+.PHONY: implibs
+
+implibs: $(addsuffix .lib,$(LIBS))
+
+%.lib: %.def
+	implib $@ $<
diff --git a/druntime/def/README.md b/druntime/def/README.md
index 9e6bd8915e..4f4cb02450 100644
--- a/druntime/def/README.md
+++ b/druntime/def/README.md
@@ -1,3 +1,4 @@
 Module-Definition (.Def) Files
 ========================================================
-These files are used by [druntime/win32.mak](../win32.mak) and [druntime/win64.mak](../win64.mak) to build D runtime library.
+The local Makefile uses these files to generate import libraries for the 32-bit Windows *OMF* toolchain (`-m32omf`).
+These import libraries are bundled with the DMD Windows packages, so this is used by https://github.com/dlang/installer.