software articles

Articles and videos on software that I like.

• Boundaries

  One of my favorites. Perhaps the best guideline to follow when thinking about how to structure a program of any size.

• Functional Core, Imperative Shell

  Another one of my favorites. Gives a practical example of using many of the concepts outlined in Boundaries.

• Choose Boring Technology (notes)

  Start by using the technologies you know how to operate. If you’re lucky enough to make something useful, the ease of operating the thing should outweigh the ease of building the thing.

• Pretty State Machine Patterns in Rust

  I’ve found myself coming back to this article several times when working on some hardware controller logic. Turns out Rust has some incredibly natural constructs for encoding state machines.

  TL:DR Have a generically typed state machine struct. Encode the states in structs. Encode the allowed transitions between states using the From trait. For example,

  // machine
  struct Machine<S> {
    state: S
  }
  
  // states
  struct State1 {}
  struct State2 {}
  struct State3 {}
  
  // transitions
  //
  // state 1 -> state 2 -> state 3
  //    ^                     |
  //    |_____________________|
  
  // transition from state 1 to state 2.
  impl From<Machine<State1>> for Machine<State2> {}
  
  // transition from state 2 to state 3.
  impl From<Machine<State2>> for Machine<State3> {}
  
  // transition from state 3 to state 1.
  impl From<Machine<State3>> for Machine<State1> {}