I had to connect an old accounting system to a web app with enhanced ui (an operator determines a payment on a visual graph of contracts between companies, plus

I had to connect an old accounting system to a web app with enhanced ui (an operator determines a payment on a visual graph of contracts between companies, plus graphs editor). There were two ways: a separate db with periodic sync, and a direct COM-connection to the old app, which was scriptable through js<=>COM library. I chose the latter, tests worked fine. After a month or so I started to notice that something is wrong with performance. Figured out that every `object.field` access through a COM proxy takes exactly 1ms. Once there’s enough data, these dots add up to tens of seconds. >_< Instead of doing a rewrite I just pushed as much of js logic as possible beyond the COM, so there’s only a constant or little amount of `a.b.c` accesses on my side. Had to write a json encoder and object serialization inside the old app to collect and pass all the data in one go. The web app was abandoned few months later for unrelated reasons.