Running examples in ‘maths.genealogy-Ex.R’ failed
The error most likely occurred in:

> base::assign(".ptime", proc.time(), pos = "CheckExEnv")
> ### Name: disciplines
> ### Title: Mathematical discipline IDs
> ### Aliases: disciplines
> 
> ### ** Examples
> 
> # Lookup the ID of any discipline involving the partial word "stat"
> disciplines("stat")
   id                                 discipline
45 62                                 Statistics
54 82 Statistical mechanics, structure of matter
> 
> # Use a regular expression to only exactly match the whole word Statistics and nothing else
> disciplines("^statistics$")
   id discipline
45 62 Statistics
> 
> # Use the above to search only for statisticians with the first name Louis
> search_id(given = "Louis", discipline = disciplines("^statistics$")$id)
Error:
✖ Please check your internet connection. If that is working, check
  whether the Maths Genealogy Project is currently down:
  <https://mathgenealogy.org/> -- if both are ok, please file a detailed
  reproducible bug report
  <https://github.com/louisaslett/maths.genealogy/issues>
Caused by error in `httr2::req_perform()`:
! Failed to perform HTTP request.
Caused by error in `curl::curl_fetch_memory()`:
! SSL peer certificate or SSH remote key was not OK [mathgenealogy.org]:
server verification failed: certificate signer not trusted. (CAfile: /etc/ssl/certs/ca-certificates.crt CRLfile: none)
Backtrace:
     ▆
  1. └─maths.genealogy::search_id(given = "Louis", discipline = disciplines("^statistics$")$id)
  2.   ├─rlang::try_fetch(...)
  3.   │ ├─base::tryCatch(...)
  4.   │ │ └─base (local) tryCatchList(expr, classes, parentenv, handlers)
  5.   │ │   └─base (local) tryCatchOne(expr, names, parentenv, handlers[[1L]])
  6.   │ │     └─base (local) doTryCatch(return(expr), name, parentenv, handler)
  7.   │ └─base::withCallingHandlers(...)
  8.   └─httr2::req_perform(...)
  9.     └─httr2:::handle_resp(req, resp, error_call = error_call)
 10.       └─rlang::cnd_signal(resp)
Execution halted