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This probably means your code is wrong. You should not raise and catch exceptions normally in Lwt promises. You should use `Lwt.fail` and `Lwt.catch`. This is described rather precisely in the documentation: https://ocsigen.org/lwt/3.2.1/api/Lwt

Another popular solution in the OCaml community is to stop using exceptions and use Result instead: https://ocsigen.org/lwt/3.2.1/api/Lwt_result

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Lots of libraries we depend on throw exceptions, e.g. yojson, postgresql, or even just the stdlib (`Invalid_argument`, anyone?).

Because the exceptions aren't statically shown at each usage point, it's hard to know what failure modes you should be watching for.

it's not my code, it's there, I can only send PR and hope.

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