If you're going to use it like Make without the build system parts, why not just have a directory of tiny scripts? More portable than either, the only boilerplate is a shebang line, and you can use static analysis tools (shellcheck), formatters (shfmt) and the like.

Take the example they've screenshotted in the readme[1]:

  alias b := build
  
  host := `uname -a`
  
  # build main
  build:
      cc *.c -o main
  
  # test everything
  test-all: build
      ./test --all
  
  # run a specific test
  test TEST: build
      ./test --test {{TEST}}

The equivalent would just be something like the following:

build.bash:

  #!/usr/bin/env bash
  set -o errexit
  cc *.c -o main

test-all.bash:

  #!/usr/bin/env bash
  set -o errexit
  "$(dirname "${BASH_SOURCE[0]}")/build.bash"
  ./test --all

test.bash:

  #!/usr/bin/env bash
  set -o errexit
  "$(dirname "${BASH_SOURCE[0]}")/build.bash"
  ./test --test "$@"

If you want to get really fancy you could make a common.bash with safety pragmas and things like the host string.

[1]: https://github.com/casey/just/blob/master/examples/screensho...