--- /dev/null
+This is a copy of libcheck, a unit testing framework for C:
+
+https://github.com/libcheck/check/
+
+The last update was on 9th December, with the following commit: ba42e7de3d62ea9d3699bf0709554b3e47a8f09e
+
+The check*.c files in this directory are the same as those in the src/
+directory in upstream. The files in the libcompat/ directory are the same as
+those in the lib/ directory upstream.
+
+lib/snprintf.c was omitted since we don't run on any platforms that don't
+provide snprintf and the upstream implementation is ~2000 lines.
+
+Steps to sync with upstream:
+
+1. Clone libcheck from the above git repository
+2. Copy files into this directory
+3. Run GNU indent on all the code
+4. Fix internal #includes
+5. Manually inspect the diff
+6. Update configure.ac, m4/check-checks.m4, meson.build files, etc
+6. Run make check, then commit and push
+
+Any changes made to files in this directory must be submitted upstream via
+a pull request: https://github.com/libcheck/check/compare
+
+This involves creating an account on GitHub, forking libcheck/check there,
+pushing the changes into a branch, and then submitting it as a pull request.