biller

Split utility bills with your roommate, ACCURATELY

Supported bill split modes

• per-person-per-day
• per-family-per-day
• per-person
• per-family

Configuration

You must properly configure biller to use it.

1. Suppose 5 people from 3 families rent an apartment:

   families:
     W&E:
       persons: [ Willow, Emersyn ]
     M&M:
       persons: [ Mckenna, Mia ]
     S:
       persons: [ Steven ]

2. And they need to pay 2 utilities and rent:

   bills:
     - desc: water
       mode: per-person-per-day
     - desc: internet
       mode: per-family-per-day
     - desc: insurance
       mode: per-person
     - desc: rent
       mode: per-family

   • Water usage is proportional to number of people occupied as well as duration of stay, so they shall use per-person-per-day.
   • Families watch TV together, so internet connectivity is proportional to number of families as well as duration of stay. That's the case for per-family-per-day.
   • Risks linked to their rental insurance is proportional to how many people lived there, regardless of how long they stayed. So per-person is used.
   • If any person from a family lived in the apartment for any time, that person shall be responsible for the area (bedroom and shared living room) they occupied, regardless of how long they stayed there. In this situation per-family is mostly applicable.

3. Finally, they all shall maintain a journal of who is currently living there:

   activities:
     # nobody was there before that
     20220101: { Willow: +1, Emersyn: +1 } # Moving in
     20220105: { Mia: +1, Steven: +1 } # Moving in
     20220110: { Willow: -1 } # Moving out
     20220115: { Mia: 0 } # temporarily not home on that day
     20220116: { Mia: 0 } # temporarily not home on that day

Usage

1. Name configuration file as data.yaml and put it in working directory.

2. Run npx biller, and follow the prompt:

    $> npx biller
    List of bills:
    [0]: water - per-person-per-day
    [1]: internet - per-family-per-day
    [2]: rent - per-family
   
    Which bill to generate? 0
    Bill start date (incl.)? (YYYYMMDD) 20220101
    Bill end date (incl.)? (YYYYMMDD) 20220131
    Amount? 33.12
    ========================
    ==== SHARES REPORT =====
    ========================
    water bill: 20220101~20220131(31d) 33.12
    20220101~20220104(4d): Willow, Emersyn
    20220105~20220109(5d): Willow, Emersyn, Mia, Steven
    20220110~20220114(5d): Emersyn, Mia, Steven
    20220115~20220116(2d): Emersyn, Steven
    20220117~20220131(15d): Emersyn, Mia, Steven
    water per person per day: $33.12/(4*2+5*4+5*3+2*2+15*3)=$0.36
    W&E: $0.36*(4*2+5*2+5*1+2*1+15*1)=$14.4
    M&M: $0.36*(5*1+5*1+15*1)=$9
    S: $0.36*(5*1+5*1+2*1+15*1)=$9.72