This patch was borrowed from Debian's package:
https://salsa.debian.org/debian-astro-team/aoflagger/-/blob/0484ef75a663e3e07738550cdade46f433a53dac/debian/patches/Use-system-provided-pybind11.patch
Description: Use system provided pybind11
Author: Ole Streicher <olebole@debian.org>
Origin: Debian
Last-Update: Mon, 30 Aug 2021 11:05:37 +0200
---
 CMakeLists.txt | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 655ea5e..824ee2a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -62,11 +62,6 @@ foreach(ExternalSubmodule IN LISTS ExternalSubmoduleDirectories)
   endif()
 endforeach()
 
-# Include aocommon/pybind11 headers
-include_directories("${CMAKE_SOURCE_DIR}/external/aocommon/include")
-add_subdirectory("${CMAKE_SOURCE_DIR}/external/pybind11")
-include_directories(SYSTEM ${pybind11_INCLUDE_DIR})
-
 find_package(
   HDF5
   COMPONENTS C CXX
@@ -101,6 +96,11 @@ find_package(PythonInterp REQUIRED)
 message(STATUS "Using python version ${PYTHON_VERSION_STRING}")
 include_directories(SYSTEM ${PYTHON_INCLUDE_DIRS})
 
+# Include pybind11 headers
+find_package(pybind11 REQUIRED)
+include_directories("${CMAKE_SOURCE_DIR}/external/aocommon/include")
+include_directories(${pybind11_INCLUDE_DIR})
+
 # boost::alignment requires Boost 1.56
 find_package(Boost 1.56.0 REQUIRED COMPONENTS date_time filesystem system
                                               unit_test_framework)
<form class='right' method='get' action='/guix/log/tests/size.scm'>
<input type='hidden' name='id' value='64041c6c2586852f6319bf695e5623e963737b71'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=64041c6c2586852f6319bf695e5623e963737b71'>root</a>/<a href='/guix/log/tests?id=64041c6c2586852f6319bf695e5623e963737b71'>tests</a>/<a href='/guix/log/tests/size.scm?id=64041c6c2586852f6319bf695e5623e963737b71'>size.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/size.scm?id=64041c6c2586852f6319bf695e5623e963737b71&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2018-11-12 23:37:13 +0100'>2018-11-12</span></td><td><a href='/guix/commit/tests/size.scm?id=9ed86fe175c15c819d6d86681c8136ff6bc927c0'>tests: Add 'test-assertm' to (guix tests).</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2017-04-07 00:17:16 +0200'>2017-04-07</span></td><td><a href='/guix/commit/tests/size.scm?id=c923f831160ddbda21d8ea1f2df4670550f3e9d8'>size: Add test to multiple 'store-profile' arguments.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2016-05-24 23:05:28 +0200'>2016-05-24</span></td><td><a href='/guix/commit/tests/size.scm?id=a371aa225c2fb0a7071609d10bbddbef353a0da5'>size: 'store-profile' takes a list of store items.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2016-04-03 14:19:09 +0200'>2016-04-03</span></td><td><a href='/guix/commit/tests/size.scm?id=a9edb211e733b8b34e67ec3b4450567e9376986f'>build: Add a Guile custom test driver using SRFI-64.</a><span class='msg-avail'>...</span></td><td>Mathieu Lirzin</td></tr>
<tr><td><span title='2015-07-12 01:27:00 +0200'>2015-07-12</span></td><td><a href='/guix/commit/tests/size.scm?id=686784d0b958478a0fd8a2fbf69755ceea2d27ec'>tests: Adjust tests for new bootstrap Guile.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2015-06-18 00:36:09 +0200'>2015-06-18</span></td><td><a href='/guix/commit/tests/size.scm?id=fcc58db68b2af59dea0cae41bc1e2df47911d588'>Add 'guix size'.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>