DuckDB build all of its bundled dependencies as separate static libraries, we don't currently bundle everything into one archive (although I think @samansmink is working on changing that). They are called libduckdb_fsst.a, libduckdb_re2.a etc and should be present in the third_party directory of your build directory, or wherever the build installed duckdb. If you link them to in your final program all symbols should be resolved.