$ export DENO_DIR="$PWD/deno_dir" ; hyperfine --prepare "rm -rf deno_dir node_modules" "deno install --env-file" "./deno install --env-file"
Benchmark 1: deno install --env-file
  Time (mean ± σ):      4.040 s ±  0.239 s    [User: 1.015 s, System: 1.355 s]
  Range (min … max):    3.666 s …  4.344 s    10 runs

Benchmark 2: ./deno install --env-file
  Time (mean ± σ):      1.999 s ±  0.065 s    [User: 0.985 s, System: 1.437 s]
  Range (min … max):    1.927 s …  2.145 s    10 runs

Summary
  './deno install --env-file' ran
    2.02 ± 0.14 times faster than 'deno install --env-file'