A3.8 · The roadmap layer · capstone
Workshop: roadmapping Portal
Four modules taught one move each. The capstone runs all of them on one real target and produces an artifact you can read — the F6 roadmap itself.
A3.4 through A3.7 each taught one part of the roadmap layer. Here they land where they were
actually used: the Portal's web surface, planned in the companion course as chapter
F6 (Phoenix). A one-line vision — serve the Portal to people — becomes a
chapter roadmap of nine rungs in three milestones, a chosen tracer, deferred seams, and a place in the program
view. The worked output reproduces the real phoenix.roadmap.md; re-ordering rungs
edits the roadmap, never a spec. Step the pipeline on the right.
The workshop pipeline · pick a stage
Five moves, one roadmap
The roadmap layer decides how we deliver the A2 backlog, separately from what we build and prove — which is the spec layer, A4. The workshop is that layer applied once, end to end, on the Portal's web surface. It runs in five stages, and each produces a named artifact.
Ladder to roadmap orders A2's value ladder into the nine-rung sequence
f6.1…f6.9 (A3.3, A3.5). Group into milestones folds the rungs
into the three F6 milestones — ship the catalog, make it live, ship to users. Fill the iteration
table gives each rung its row: Ships, Demo, Harness, Feedback asked
(A3.5). Choose the tracer picks the first end-to-end thread, F6.1, and names the seams
deferred (A3.4, A3.7). Place in the program sets the chapter beside the bot as a parallel
surface over the one facade (A3.6).
Over all five sits the master invariant, quoted verbatim from the file: “The web layer calls only the
Portal facade and renders only the closed %Portal.Error{}
set. No controller, LiveView, plug, or template names Portal.Engine, a repo, or
GenServer.call.” The output is not invented — it reproduces the real
phoenix.roadmap.md, line for line.
The roadmap layer is five moves applied once, end to end — order the ladder, group milestones, fill the iteration table, choose the tracer, place the chapter in the program.
The workshop's output reproduces the real phoenix.roadmap.md. Each rung points at
its f6.N.md spec and defines no behaviour; re-ordering rungs edits the roadmap,
never a spec.
The workshop is the roadmap layer applied once on the Portal — the delivery plan Part VII executes.
The three dives
Each dive carries one pass of the workshop on the real F6 chapter, in the arc ladder to roadmap → choose the tracer → the program view: first turn the value ladder into a chapter roadmap with milestones and the iteration table, then pick the tracer bullet and name the deferred seams, then place the chapter beside the bot in a program view over one facade. Read them in order — A3.8.1 starts.
Ladder to roadmap
Order A2's value ladder into the nine-rung F6 ladder, group it into three milestones, and fill each rung's iteration row — ships, demo, harness, feedback.
Choose the tracer
Pick the tracer bullet — F6.1, request to facade to render — as the first end-to-end thread, and name the seams deferred to later rungs.
The program view
Set the chapter roadmap beside the bot in a program view: web (F6) and bot (F10) as parallel surfaces over the one facade — the plan Part VII executes.
A3.8 is the chapter capstone: it applies A3.4–A3.7 on the Portal, reproducing the real
phoenix.roadmap.md. It runs one layer up from the decomposition capstone
A2.07 · Workshop: decomposing Portal,
which produced the backlog this layer plans into delivery. Return to the
A3 chapter navigation to continue.
References
The delivery-planning tradition the workshop runs on, and the chapter modules it applies in sequence.
Sources
- Humble & Farley — Continuous Delivery — ordering work into thin, demoable increments that keep the system releasable.
- Beck, K. — Extreme Programming Explained — the planning game: order the work into small releases, defer the design.
- Hunt & Thomas — The Pragmatic Programmer — tracer bullets and naming what is not yet decided.
Related in this course
- A3.8.1 · Ladder to roadmap
- A3.8.2 · Choose the tracer
- A3.8.3 · The program view
- A2.07 · Workshop: decomposing Portal — the decomposition capstone one layer below.
- A3.3 · Anatomy of a roadmap.md — the document this workshop produces.
- A3 · The road ahead — where the spec layer takes each rung next.
- A3 · The roadmap layer — the chapter.
- F6 · The Portal on the web (Phoenix) — the real chapter this roadmap plans.