diff --git a/lib/process_shared/posix_call.rb b/lib/process_shared/posix_call.rb
deleted file mode 100644
index e3ed9b7..0000000
--- a/lib/process_shared/posix_call.rb
+++ /dev/null
@@ -1,29 +0,0 @@
-# require 'process_shared/libc' - circular dependency here...
-
-module ProcessShared
-  module PosixCall
-    # Replace methods in +syms+ with error checking wrappers that
-    # invoke the original method and raise a {SystemCallError} with
-    # the current errno if the return value is an error.
-    #
-    # Errors are detected if the block returns true when called with
-    # the original method's return value.
-    def error_check(*syms, &is_err)
-      unless block_given?
-        is_err = lambda { |v| (v == -1) }
-      end
-
-      syms.each do |sym|
-        method = self.method(sym)
-        define_singleton_method(sym) do |*args|
-          ret = method.call(*args)
-          if is_err.call(ret)
-            raise SystemCallError.new("error in #{sym}", LibC.errno)
-          else
-            ret
-          end
-        end
-      end
-    end
-  end
-end
diff --git a/lib/process_shared/rt.rb b/lib/process_shared/rt.rb
deleted file mode 100644
index 672d386..0000000
--- a/lib/process_shared/rt.rb
+++ /dev/null
@@ -1,21 +0,0 @@
-require 'process_shared/posix_call'
-require 'process_shared/psem'
-
-module ProcessShared
-  module RT
-    extend FFI::Library
-    extend PosixCall
-
-    # FIXME: mac and linux OK, but what about everything else?
-    if FFI::Platform.mac?
-      ffi_lib 'c'
-    else
-      ffi_lib 'rt'
-    end
-
-    attach_function :shm_open, [:string, :int, :mode_t], :int
-    attach_function :shm_unlink, [:string], :int
-
-    error_check :shm_open, :shm_unlink
-  end
-end