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Greenfield: build it from an idea

Start from an empty folder and a request for a command-line tool that splits shared expenses between friends. The whole demo is in demos/expense-splitter/greenfield.

For a first try, start with level 1:

Build a small command-line tool that helps a group of friends split shared expenses and see who owes whom.

The other levels let you compare how more detail changes the result.

Run it​

  1. Create an empty project outside this repository, and commit a starting point.

  2. Install Open Forge and the Development Toolkit:

    open-forge install
    open-forge extension install development-toolkit

    Decisions, and Documents such as a Vision or Architecture, come from these Extensions, not from the base install.

  3. Give your agent the level 1 request above, or choose another level for a comparison:

    LevelRequest
    1One sentence
    2A short brief, with money handling deliberately left unsaid
    3The brief plus expected results, including rounding
    4A Vision, an Architecture, two Decisions, and scenarios as records

    At level 4, copy the records into your project first, as the level 4 README describes.

  4. Answer the agent's questions as a product owner would, and accept the proposals you agree with.

  5. Check the result against the checklist.

What to watch​

  • Money. Splitting 10.00 three ways in floating point gives 3.3333333333333335. Does the agent notice that money needs whole cents, or ask about it, before you tell it?
  • Rounding. Someone has to pay the extra cent. Does the agent choose a rule and tell you, or does it happen by accident?
  • Reasons. Do the choices end up as Decisions with their reasons, or only in the conversation?
  • Level 4. With the records in place, does the agent follow them, or rediscover them?

Next: Grow your own framework.