At work, we were discussing how to serialize some structured data as an HTTP request header value. I reflexively said "ascii subset of JSON without newlines," b

At work, we were discussing how to serialize some structured data as an HTTP request header value. I reflexively said "ascii subset of JSON without newlines," but that was rejected for some reasons (maybe too much punctuation, verbose for Chinese...). Someone came up with pipe-separated fields, but then that was rejected too. The reason was something like "some customers used to have proxies that would reject any headers that include a pipe character." My point is that voodoo programming isn't always due to lack of due diligence. It's due to knowing that something went wrong with something in the past, but for which there is no evidence, and about which you would be able to do nothing. My preference is to deploy it anyway, see if it breaks, and if necessary work it out with the customer after the fact. That's unpopular for good and obvious reasons, so no pipe characters.