Recently I found time to track down a file descriptor leaking bug in coquelicot that annoyed us for a while. Essentially at least every 404 leaked some FDs on the @path/.lock path.
it seems that my fix only helped partially and this is also due to a problem in the lockfile library itself:
Applying this patch seems to get rid off the leaking FDs completely in the end.
https://github.com/ahoward/lockfile/pull/13/commits/27c0f5b291211d1e5d8b8d27...
best
ng