From a quick test, about 5x faster:

    tavianator@tachyon $ cat bench.mjs
    #!/usr/bin/env node

    import { fdir } from "fdir";

    console.log(new fdir().withFullPaths().crawl("/home/tavianator/code/android").sync().length);
    tavianator@tachyon $ hyperfine -w1 "node ./bench.mjs" "bfs ~/code/android -false"
    Benchmark 1: node ./bench.mjs
      Time (mean ± σ):      2.073 s ±  0.031 s    [User: 1.372 s, System: 1.260 s]
      Range (min … max):    2.022 s …  2.128 s    10 runs

    Benchmark 2: bfs ~/code/android -false
      Time (mean ± σ):     417.5 ms ±   6.8 ms    [User: 592.3 ms, System: 2487.7 ms]
      Range (min … max):   405.2 ms … 429.7 ms    10 runs

    Summary
      bfs ~/code/android -false ran
        4.97 ± 0.11 times faster than node ./bench.mjs

Is there a way to call it that doesn't require holding all the paths in memory simultaneously?