diff -ruN a/config/nim.cfg b/config/nim.cfg
--- a/config/nim.cfg	2018-02-15 00:45:38.251038499 +0100
+++ b/config/nim.cfg	2018-02-15 00:46:48.937858896 +0100
@@ -231,3 +231,7 @@
 
 # Configuration for the Tiny C Compiler:
 tcc.options.always = "-w"
+
+# Enable libucontext
+gcc.options.linker %= "-lucontext"
+llvm_gcc.options.linker %= "-lucontext"