The Sibling Quartet

"One brain. Many bodies. Bonfire is a body, not another brain."

Four Repos, One Identity

Bonfire only makes sense as the fourth member of a family. There are four repositories, and exactly one identity — Pippa — running through all of them:

                 cwkPippa  —  the brain
          (identity · conversation · memory · routing)
                          |
     +--------------------+--------------------+
     |                    |                    |
  cwkCinder           cwkEmber             cwkBonfire
  workspace           image engine         music engine
  (Photoshop          (generates,          (analyzes / teaches,
   sidecar)            feeds Cinder)        feeds its own UI)

cwkPippa is the brain: it owns identity, conversation storage, memory, and brain routing. The other three are client surfaces of that one brain — not parallel Pippas. This matters more than it looks: it's the difference between one coherent self that appears in many places and four chatbots that happen to share a name.

Ember Is to Images What Bonfire Is to Music

The two engines are deliberate mirrors. Ember owns image generation — model loading, sampling, the lot — and exposes an API that Cinder, the creative workspace, consumes. Bonfire owns music analysis and understanding, and exposes an API that its own built-in UI consumes (and a future Live bridge could, too). Same posture, different medium:

Ember → Cinder: engine generates pixels, sidecar arranges them on a Photoshop canvas.
Bonfire → its UI: engine produces a music model, the Konva UI renders it as fretboard / waveform / grid.

Ember was built first and opened its API; Cinder became a consumer afterward. Bonfire follows the same order — finish the engine, open the API, let sidecars come after (you'll see this as a hard rule in Track 4).

Triad Became Quartet

Before Bonfire there were three: Pippa, Cinder, Ember — an image-centric triad. Bonfire makes it a quartet by adding the music medium. The lesson isn't "more repos." It's that the shape generalized cleanly: a brain plus engines-and-surfaces is a pattern you can extend to a new medium without redesigning the family. Add a video engine tomorrow and the shape still holds.

Code

The quartet — one brain, three surfaces·text

                 cwkPippa  —  the brain
          (identity · conversation · memory · routing)
                          |
     +--------------------+--------------------+
     |                    |                    |
  cwkCinder           cwkEmber             cwkBonfire
  workspace           image engine         music engine
  (Photoshop          (generates,          (analyzes / teaches,
   sidecar)            feeds Cinder)        feeds its own UI)

# Bonfire's Sidekick binds to a cwkPippa conversation.
# It never stands up its own brain. (Track 8 Lesson 1.)

Exercise

Sketch a product you'd build as 'one brain, many surfaces.' Name the single thing that must NOT be duplicated across surfaces (the identity/state), and name two surfaces that would each render it differently. If you can't name the un-duplicated core, you don't have a brain yet — you have several apps.

Hint

The un-duplicated core is whatever would cause 'drift' if copied: user identity, the canonical document, the conversation history. Surfaces are allowed to differ; the core is not allowed to fork.