Question: is there a bash abstraction?

As build steps get more complicated (at the moment I try to introduce a build-target dir in order to separate src from build artifacts) I want do modularize my bash-scripts. I think  `&&` is not enough ...

```
terraform-plan
  {product (str terraform-build-dir "/proposed.plan")
   update! #$ ["cd" terraform-build-dir "&&"
                      "terraform" "plan" "-out" product]
```