diff --git a/test/tool/net/BUILD.mk b/test/tool/net/BUILD.mk
index c1a7ebd4f..a1ac357b1 100644
--- a/test/tool/net/BUILD.mk
+++ b/test/tool/net/BUILD.mk
@@ -71,11 +71,17 @@ o/$(MODE)/test/tool/net/%.dbg:					\
 		$(APE_NO_MODIFY_SELF)
 	@$(APELINK)
 
+
+o/$(MODE)/tool/net/tester/.init.lua.zip.o: private    \
+        ZIPOBJ_FLAGS += \
+		    -B
+
 .PRECIOUS: o/$(MODE)/test/tool/net/redbean-tester
 o/$(MODE)/test/tool/net/redbean-tester.dbg:			\
 		$(TOOL_NET_DEPS)				\
 		o/$(MODE)/tool/net/redbean.o			\
 		$(TOOL_NET_REDBEAN_LUA_MODULES)			\
+		o/$(MODE)/tool/net/tester/.init.lua.zip.o       \
 		o/$(MODE)/tool/net/demo/seekable.txt.zip.o	\
 		o/$(MODE)/tool/net/net.pkg			\
 		$(CRT)						\
diff --git a/tool/net/tester/.init.lua b/tool/net/tester/.init.lua
new file mode 100644
index 000000000..6fa68a912
--- /dev/null
+++ b/tool/net/tester/.init.lua
@@ -0,0 +1,33 @@
+-- special script called by main redbean process at startup
+HidePath('/usr/share/zoneinfo/')
+HidePath('/usr/share/ssl/')
+
+-- 20Ki, for certain autobahn tests
+ProgramMaxPayloadSize(20 * 1024 * 1024)
+
+function OnHttpRequest()
+  if GetPath() == "/ws" then
+    ws.Write(nil) -- upgrade without sending a response
+    coroutine.yield()
+
+    local fds = {[GetClientFd()] = unix.POLLIN}
+    -- simple echo server
+    while true do
+      unix.poll(fds)
+      local s, t = ws.Read()
+      if t == ws.CLOSE then
+        return
+      elseif t == ws.TEXT then
+        ws.Write(s, ws.TEXT)
+        coroutine.yield()
+      elseif t == ws.BIN then
+        ws.Write(s, ws.BIN)
+        coroutine.yield()
+      end
+    end
+  else
+    Route()
+  end
+end
+
+