lboost_system is not getting built

I'm trying to build boost 1.87 from source on Debian 12.2.0
```
git checkout boost-1.87.0
./bootstrap.sh --with-libraries=system,thread
sudo ./b2 install
```
I've also tried
```
sudo ./b2 install --with-system --with-thread
```
Then
```
find /usr/local/lib -name "libboost_thread*"
/usr/local/lib/libboost_thread.so.1.87.0
/usr/local/lib/cmake/boost_thread-1.87.0/libboost_thread-variant-static.cmake
/usr/local/lib/cmake/boost_thread-1.87.0/libboost_thread-variant-shared.cmake
/usr/local/lib/libboost_thread.so
/usr/local/lib/libboost_thread.a
find /usr/local/lib -name "libboost_system*"
# returns nothing
```