Breadboarding — Affordance Wiring for UI and Code

Transform a workflow description into affordance tables showing UI and Code affordances with their wiring. Use to map existing systems or design new ones from shaped parts.

Breadboarding

Breadboarding transforms a workflow description into a complete map of affordances and their relationships. The output is always a set of tables showing numbered UI and Code affordances with their Wires Out and Returns To relationships. The tables are the truth. Mermaid diagrams are optional visualizations for humans.

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Use Cases

Breadboarding serves two functions:

1. Mapping an Existing System

You don't understand how an existing system works in its concrete details. You have a workflow you're trying to understand — explaining how something happens or why something doesn't happen.

Input:

• Code repo(s) to analyze
• Workflow description (always from the perspective of an operator trying to make an effect happen — through UI or as a caller)

Output:

• UI Affordances table
• Code Affordances table
• (Optional) Mermaid visualization

Note: If the workflow spans multiple applications (frontend + backend), create ONE breadboard that tells the full story. Label places to show which system they belong to.

2. Designing from Shaped Parts

You have a new system sketched as an assembly of parts (mechanisms) per shaping. You need to detail out the concrete mechanism and show how those parts interact as a system.

Input:

• Parts list (mechanisms from shaping)
• The R (requirement/outcome) the parts are meant to achieve
• Existing system (optional) — if the new parts must interoperate with existing code

Output:

• UI Affordances table
• Code Affordances table
• (Optional) Mermaid visualization

Mixtures

Often you have both: an existing system that must remain as-is, plus new pieces or changes defined in a shape. In this case, breadboard both together — the existing affordances and the new ones — showing how they connect.

3. Reading a Whiteboard Breadboard

Hand-drawn or whiteboard breadboards use a visual stacking format rather than tables. The same concepts apply (Places, affordances, wiring) but the layout conventions differ.

Visual conventions:

Element	How it appears
Place	Colored block (often pink/purple) at the top of a vertical stack
Affordances in a place	Blocks stacked underneath the place block — containment is shown by vertical position in the stack
Code affordances	Typically float between place stacks, not inside them
Place loader	A code affordance positioned at the top-left of the place block — describes the data/inputs needed to render that place
Wires Out	Solid arrows between blocks
Returns To	Dashed arrows between blocks
Conditionals	Indented blocks within a stack, often a different color (e.g., green), showing if/else branches
Place references	_ prefix on a place name within a stack (same as _PlaceName convention)
Uncertain/tentative	? prefix or ~ prefix on an affordance name, or dashed borders — indicates the affordance is speculative
Containing box	A large boundary drawn around multiple stacks — groups affordances by system or responsibility boundary (e.g., "HireEZ" box)
Notes/annotations	Freeform text near elements — context, open questions, or rationale

How to read a whiteboard breadboard:

1. Identify places — Find the colored header blocks at the top of each stack
2. Read each stack top-to-bottom — Everything stacked under a place belongs to that place
3. Find loaders — Code affordances at the top-left of a place block describe what data is needed to render
4. Trace wiring — Follow arrows between stacks for control flow (solid) and data flow (dashed)
5. Note conditionals — Indented blocks with different colors show branching logic within a place
6. Check containing boxes — Large boundaries indicate system/responsibility boundaries
7. Flag speculative items — ? and ~ prefixed items are uncertain and may not survive shaping

Translating to tables: When converting a whiteboard breadboard to standard affordance tables, map each stack to its Place, enumerate the affordances top-to-bottom, and capture the arrows as Wires Out / Returns To relationships. Loaders become code affordances with Returns To pointing at the UI affordances they feed.

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Core Concepts

Places

A Place is a bounded context of interaction. While you're in a Place:

• You have a specific set of affordances available to you
• You cannot interact with affordances outside that boundary
• You must take an action to leave

Place is perceptual, not technical. It's not about URLs or components — it's about what the user experiences as their current context. A Place is "where you are" in terms of what you can do right now.

The Blocking Test

The simplest test for whether something is a different Place: Can you interact with what's behind?

Answer	Meaning
No	You're in a different Place
Yes	Same Place, with local state changes

Examples

UI Element	Blocking?	Place?	Why
Modal	Yes	Yes	Can't interact with page behind
Confirmation popover	Yes	Yes	Must respond before returning (limit case of modal)
Edit mode (whole screen transforms)	Yes	Yes	All affordances changed
Checkbox reveals extra fields	No	No	Surroundings unchanged
Dropdown menu	No	No	Can click away, non-blocking
Tooltip	No	No	Informational, non-blocking

Local State vs Place Navigation

When a control changes state, ask: did everything change, or just a subset while the surroundings stayed the same?

Type	What happens	How to model
Local state	Subset of UI changes, surroundings unchanged	Same Place, conditional N → dependent Us
Place navigation	Entire screen transforms, or blocking overlay	Different Places

Mode-Based Places

When a mode (like "edit mode") transforms the entire screen — different buttons, different affordances everywhere — model as separate Places:

text

PLACE: CMS Page (Read Mode)
PLACE: CMS Page (Edit Mode)

The state flag (e.g., editMode$) that switches between them is a navigation mechanism, not a data store. Don't include it as an S in either Place.

Three Questions for Any Control

For any UI affordance, ask:

1. Where did I come from to see this?
2. Where am I now?
3. Where do I go if I act on it?

If the answer to #3 is "everything changes" or "I can't interact with what's behind until I respond," that's navigation to a different Place.

Labeling Conventions

Pattern	Use
PLACE: Page Name	Standard page/route
PLACE: Page Name (Mode)	Mode-based variant of a page
PLACE: Modal Name	Modal dialog
PLACE: Backend	API/database boundary

When spanning multiple systems, label with the system: PLACE: Checkout Page (frontend), PLACE: Payment API (backend).

Place IDs

Places are first-class elements in the data model. Each Place gets an ID:

#	Place	Description
P1	CMS Page (Read Mode)	View-only state
P2	CMS Page (Edit Mode)	Editing state with page-level controls
P2.1	widget-grid (letters)	Subplace: letter editing widget within P2
P3	Letter Form Modal	Form for adding/editing letters
P4	Backend	API resolvers and database

Place IDs enable:

• Explicit navigation wiring — wire → P2 instead of to an affordance inside
• Containment tracking — each affordance declares which Place it belongs to
• Consistent Mermaid subgraphs — subgraph ID matches Place ID

Place References

When a nested place has lots of internal affordances and would clutter the parent, you can detach it:

1. Put a reference node in the parent place using underscore prefix: _letter-browser
2. Define the full place separately with all its internals
3. Wire from the reference to the place: _letter-browser --> letter-browser

The reference is a UI affordance — it represents "this widget/component renders here" in the parent context.

Rendering diagram...

In affordance tables, list the reference as a UI affordance:

#	Affordance	Control	Wires Out
U1	Edit button	click	→ N1
_letter-browser	Widget reference	—	→ P3

Style place references with a dashed border to distinguish them:

text

classDef placeRef fill:#ffb6c1,stroke:#d87093,stroke-width:2px,stroke-dasharray:5 5
class U_LB placeRef

Modes as Places

When a component has distinct modes (read vs edit, viewing vs editing, collapsed vs expanded), model them as separate places — they're different perceptual states for the user.

If one mode includes everything from another plus more, show this with a place reference inside the extended place:

text

P3: letter-browser (Read)    — base state
P4: letter-browser (Edit)    — contains _letter-browser (Read) + new affordances

The reference shows composition: "everything in P3 appears here, plus these additions."

Rendering diagram...

In affordance tables for P4, the reference shows inheritance:

#	Affordance	Control	Wires Out	Notes
_letter-browser (Read)	Inherits all of P3	—	→ P3
U3	Add button	click	→ N3	NEW
U4	Edit button	click	→ N4	NEW

Subplaces

A subplace is a defined subset of a Place — a contained area that groups related affordances. Use subplaces when:

• A Place contains multiple distinct widgets or sections
• You're detailing one part of a larger Place
• You want to show what's in scope vs out of scope

Notation: Use hierarchical IDs — P2.1, P2.2, etc. for subplaces of P2.

text

| # | Place | Description |
|---|-------|-------------|
| P2 | Dashboard | Main dashboard page |
| P2.1 | Sales widget | Subplace: sales metrics |
| P2.2 | Activity feed | Subplace: recent activity |

In affordance tables, use the subplace ID to show containment:

text

| U3 | P2.1 | sales-widget | "Refresh" button | click | → N4 | — |
| U7 | P2.2 | activity-feed | activity list | render | — | — |

In Mermaid: Nest the subplace subgraph inside the parent. Use the same background color (no distinct fill) — the subplace is part of the parent, not a separate Place:

Rendering diagram...

Placeholder for out-of-scope content: When detailing one subplace, add a placeholder sibling to show there's more on the page:

text

otherContent[["... other page content ..."]]

This tells readers: "we're zooming in on P2.1, but P2 contains more that we're not detailing."

Containment vs Wiring

These are two different relationships in the data model:

Relationship	Meaning	Where Captured
Containment	Affordance belongs to / lives in a Place	Place column (set membership)
Wiring	Affordance triggers / calls something	Wires Out column (control flow)

Containment is set membership: U1 ∈ P1 means U1 is a member of Place P1. Every affordance belongs to exactly one Place.

Wiring is control flow: U1 → N1 means U1 triggers N1. An affordance can wire to anything — other affordances or Places.

The Place column answers: "Where does this affordance live?" The Wires Out column answers: "What does this affordance trigger?"

Navigation Wiring

When an affordance causes navigation (user "goes" somewhere), wire to the Place itself, not to an affordance inside:

text

✅ N1 Wires Out: → P2          (navigate to Edit Mode)
❌ N1 Wires Out: → U3          (wiring to affordance inside P2)

This makes navigation explicit in the tables. The Place is the destination; specific affordances inside become available once you arrive.

In Mermaid, this becomes:

text

N1 --> P2

The subgraph ID matches the Place ID, so the wire connects to the Place boundary.

Affordances

Things you can act upon:

• UI affordances (U): inputs, buttons, displayed elements, scroll regions
• Code affordances (N): methods, subscriptions, data stores, framework mechanisms

Wiring

How affordances connect to each other:

Wires Out — What an affordance triggers or calls (control flow):

• Call wires: one affordance calls another
• Write wires: code writes to a data store
• Navigation wires: routing to a different place

Returns To — Where an affordance's output flows (data flow):

• Return wires: function returns value to its caller
• Read wires: data store is read by another affordance

This separation makes data flow explicit. Wires Out show control flow (what triggers what). Returns To show data flow (where output goes).

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The Output: Affordance Tables

The tables are the truth. Every breadboard produces these:

Places Table

#	Place	Description
P1	Search Page	Main search interface
P2	Detail Page	Individual result view

UI Affordances Table

#	Place	Component	Affordance	Control	Wires Out	Returns To
U1	P1	search-detail	search input	type	→ N1	—
U2	P1	search-detail	loading spinner	render	—	—
U3	P1	search-detail	results list	render	—	—
U4	P1	search-detail	result row	click	→ P2	—

Code Affordances Table

#	Place	Component	Affordance	Control	Wires Out	Returns To
N1	P1	search-detail	activeQuery.next()	call	→ N2	—
N2	P1	search-detail	activeQuery subscription	observe	→ N3	—
N3	P1	search-detail	performSearch()	call	→ N4, → N5, → N6	—
N4	P1	search.service	searchOneCategory()	call	→ N7	→ N3
N5	P1	search-detail	loading	write	store	→ U2
N6	P1	search-detail	results	write	store	→ U3
N7	P1	typesense.service	rawSearch()	call	—	→ N4

Data Stores Table

#	Place	Store	Description
S1	P1	results	Array of search results
S2	P1	loading	Boolean loading state

Column Definitions

Column	Description
#	Unique ID (P1, P2... for Places; U1, U2... for UI; N1, N2... for Code; S1, S2... for Stores)
Place	Which Place this affordance belongs to (containment)
Component	Which component/service owns this
Affordance	The specific thing you can act upon
Control	The triggering event: click, type, call, observe, write, render
Wires Out	What this triggers: → N4, → P2 (control flow, including navigation)
Returns To	Where output flows: → N3 or → U2, U3 (data flow)

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Procedures

For Mapping an Existing System

See Example A below for a complete worked example.

Step 1: Identify the flow to analyze

Pick a specific user journey. Always frame it as an operator trying to do something:

• "Land on /search, type query, scroll for more, click result"
• "Call the payment API with a card token, expect a charge to be created"

Step 2: List all places involved

Walk through the journey and identify each distinct place the user visits or system boundary crossed.

Step 3: Trace through the code to find components

Starting from the entry point (route, API endpoint), trace through the code to find every component touched by that flow.

Step 4: For each component, list its affordances

Read the code. Identify:

• UI: What can the user see and interact with?
• Code: What methods, subscriptions, stores are involved?

Step 5: Name the actual thing, not an abstraction

If you write "DATABASE", stop. What's the actual method? (userRepo.save()). Every affordance name must be something real you can point to in the code.

Step 6: Fill in Control column

For each affordance, what triggers it? (click, type, call, observe, write, render)

Step 7: Fill in Wires Out

For each affordance, what does it trigger? Read the code — what does this method call? What does this button's handler invoke?

Step 8: Fill in Returns To

For each affordance, where does its output flow?

• Functions that return values → list the callers that receive the return
• Data stores → list the affordances that read from them
• No meaningful output → use —

Step 9: Add data stores as affordances

When code writes to a property that is later read by another affordance, add that property as a Code affordance with control type write.

Step 10: Add framework mechanisms as affordances

Include things like cdr.detectChanges() that bridge between code and UI rendering. These show how state changes actually reach the UI.

Step 11: Verify against the code

Read the code again. Confirm every affordance exists and the wiring matches reality.

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For Designing from Shaped Parts

See Example B below for a complete worked example including slicing.

Step 1: List each part from the shape

Take each mechanism/part identified in shaping and write it down.

Step 2: Translate parts into affordances

For each part, identify:

• What UI affordances does this part require?
• What Code affordances implement this part?

Step 3: Verify every U has a supporting N

For each UI affordance, check: what Code affordance provides its data or controls its rendering? If none exists, add the missing N.

Step 4: Classify places as existing or new

For each UI affordance, determine whether it lives in:

• An existing place being modified
• A new place being created

Step 5: Wire the affordances

Fill in Wires Out and Returns To for each affordance. Trace through the intended behavior — what calls what? What returns where?

Step 6: Connect to existing system (if applicable)

If there's an existing codebase:

• Identify the existing affordances the new ones must connect to
• Add those existing affordances to your tables
• Wire the new affordances to them

Step 7: Check for completeness

• Every U should have an N that feeds it
• Every N should have either Wires Out or Returns To (or both)
• Handlers → should have Wires Out
• Queries → should have Returns To
• Data stores → should have Returns To

Step 8: Treat user-visible outputs as Us

Anything the user sees (including emails, notifications) is a UI affordance and needs an N wiring to it.

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Key Principles

Never use memory — always check the data

When tracing a flow backwards, don't follow the path you remember. Scan the Wires Out column for ALL affordances that wire to your target.

When filling in the tables, read each row systematically. Don't rely on what you think you know.

The tables are the source of truth. Your memory is unreliable.

Every affordance name must exist (when mapping)

When mapping existing code, never invent abstractions. Every name must point to something real in the codebase.

Mechanisms aren't affordances

An affordance is something you can act upon that has meaningful identity in the system. Several things look like affordances but are actually just implementation mechanisms:

Type	Example	Why it's not an affordance
Visual containers	modal-frame wrapper	You can't act on a wrapper — it's just a Place boundary
Internal transforms	letterDataTransform()	Implementation detail of the caller — not separately actionable
Navigation mechanisms	modalService.open()	Just the "how" of getting to a Place — wire to the destination directly

These aren't always obvious on first draft. When reviewing your affordance tables, double-check each Code affordance and ask:

"Is this actually an affordance, or is it just detailing the mechanism for how something happens?"

If it's just the "how" — skip it and wire directly to the destination or outcome.

Examples:

text

❌ N8 --> N22 --> P3     (N22 is modalService.open — just mechanism)
✅ N8 --> P3             (handler navigates to modal)

❌ N6 --> N20 --> S2     (N20 is data transform — internal to N6)
✅ N6 --> S2             (callback writes to store)

❌ U7: modal-frame       (wrapper — just the boundary of P3)
✅ U8: Save button       (actionable)

The handler navigates to P3. The callback writes to the store. The modal IS P3. The mechanisms are implicit.

Two flows: Navigation and Data

A breadboard captures two distinct flows:

Flow	What it tracks	Wiring
Navigation	Movement from Place to Place	Wires Out → Places
Data	How state populates displays	Returns To → Us

These are orthogonal. You can have navigation without data changes, and data changes without navigation.

When reviewing a breadboard, trace both flows:

1. Navigation flow: Can you follow the user's journey from Place to Place?
2. Data flow: For every U that displays data, can you trace where that data comes from?

Every U that displays data needs a source

A UI affordance that displays data must have something feeding it — either a data store (S) or a code affordance (N) that returns data.

text

❌ U6: letter list (no incoming wire — where does the data come from?)
✅ S1 -.-> U6 (store feeds the display)
✅ N4 -.-> U6 (query result feeds the display)

If a display U has no data source wiring into it, either:

1. The source is missing from the breadboard
2. The U isn't real

This is easy to miss when focused on navigation. Always ask: "This U shows data — where does that data come from?"

Every N must connect

If a Code affordance has no Wires Out AND no Returns To, something is wrong:

• Handlers → should have Wires Out (what they call or write)
• Queries → should have Returns To (who receives their return value)
• Data stores → should have Returns To (which affordances read them)

Side effects need stores

An N that appears to wire nowhere is suspicious. If it has side effects outside the system boundary (browser URL, localStorage, external API, analytics), add a store node to represent that external state:

text

❌ N41: updateUrl()           (wires to... nothing?)
✅ N41: updateUrl() → S15     (wires to Browser URL store)

This makes the data flow explicit. The store can also have return wires showing how external state flows back in:

Rendering diagram...

Common external stores to model:

• Browser URL — query params, hash fragments
• localStorage / sessionStorage — persisted client state
• Clipboard — copy/paste operations
• Browser History — navigation state

Separate control flow from data flow

Wires Out = control flow (what triggers what) Returns To = data flow (where output goes)

This separation makes the system's behavior explicit.

Show navigation inline, not as loops

Routing is a generic mechanism every page uses. Instead of drawing all navigation through a central Router affordance, show Router navigate() inline where it happens and wire directly to the destination place.

Place stores where they enable behavior, not where they're written

A data store belongs in the Place where its data is consumed to enable some effect — not where it's produced. Writes from other Places are "reaching into" that Place's state.

To determine where a store belongs:

1. Trace read/write relationships — Who writes? Who reads?
2. The readers determine placement — that's where behavior is enabled
3. If only one Place reads, the store goes inside that Place

Example: A changedPosts array is written by a Modal (when user confirms changes) but read by a PAGE_SAVE handler (when user clicks Save). The store belongs with the PAGE_SAVE handler — that's where it enables the persistence operation.

Only extract to shared areas when truly shared

Before putting a store in a separate DATA STORES section, verify it's actually read by multiple Places. If it only enables behavior in one Place, it belongs inside that Place.

Nest stores in the subcomponent that reads them

Within a Place, put stores in the subcomponent where they enable behavior. If a store is read by a specific handler, put it in that handler's component — not floating at the Place level.

Backend is a Place

The database and resolvers aren't floating infrastructure — they're a Place with their own affordances. Database tables (S) belong inside the Backend Place alongside the resolvers (N) that read and write them.

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Catalog of Parts and Relationships

This section provides a complete reference of everything that can appear in a breadboard.

Elements

Element	ID Pattern	What It Is	What Qualifies
Place	P1, P2, P3...	A bounded context of interaction	Blocking test: can't interact with what's behind
Subplace	P2.1, P2.2...	A defined subset within a Place	Groups related affordances within a larger Place
Place Reference	_PlaceName	UI affordance pointing to a detached place	Complex nested place defined separately
UI Affordance	U1, U2, U3...	Something the user can see or interact with	Inputs, buttons, displays, scroll regions
Code Affordance	N1, N2, N3...	Something in code you can act upon	Methods, subscriptions, handlers, framework mechanisms
Data Store	S1, S2, S3...	State that persists and is read/written	Properties, arrays, observables that hold data
Chunk	—	A collapsed subsystem	One wire in, one wire out, many internals
Placeholder	—	Out-of-scope content marker	Shows context without detailing

Relationships

Relationship	Syntax	Meaning	Example
Containment	Place column	Affordance belongs to Place	U3 in Place P2.1
Wires Out	→ X	Control flow: triggers/calls	→ N4, → P2
Returns To	→ X (in Returns To column)	Data flow: output goes to	→ U6, → N3
Abbreviated flow	|label|	Intermediate steps omitted	S4 -.-> |view query| U6
Parent-child	Hierarchical ID	Subplace belongs to Place	P2.1 is child of P2

Containment vs Wiring

Relationship	Meaning	Where Captured
Containment	Affordance belongs to / lives in a Place	Place column (set membership)
Wiring	Affordance triggers / calls something	Wires Out column (control flow)

Containment is set membership: U1 ∈ P1 means U1 is a member of Place P1. Wiring is control flow: U1 → N1 means U1 triggers N1.

What Qualifies as Each Element

Place (P):

• Passes the blocking test — can't interact with what's behind
• Examples: modal, edit mode (whole screen transforms), route/page
• Not: dropdown, tooltip, checkbox revealing fields

Place Reference (_PlaceName):

• A UI affordance that represents a detached place
• Use when a nested place has many affordances and would clutter the parent
• Examples: _letter-browser, _user-profile-widget
• Wires to the full place definition: _letter-browser --> P3

UI Affordance (U):

• User can see it or interact with it
• Examples: button, input, list, spinner, displayed text
• Not: wrapper elements, layout containers

Code Affordance (N):

• Has meaningful identity — you can point to it in code
• Examples: handleSubmit(), query$ subscription, detectChanges()
• Not: internal transforms, navigation mechanisms (see below)

Data Store (S):

• State that is written and read
• Examples: results array, loading boolean, changedPosts list
• External stores: Browser URL, localStorage, Clipboard — represent state outside the app boundary
• Not: config that's set once and never changes (consider as config affordance)

Verification Checks

Check	Question	If No...
Every U that displays data	Does it have an incoming wire (via Wires Out or Returns To)?	Add the data source
Every N	Does it have Wires Out or Returns To (or both)?	Investigate — may be dead code or missing wiring
Every S	Does something read from it (Returns To)?	Investigate — may be unused
Navigation mechanisms	Is this N just the "how" of getting somewhere?	Wire directly to Place instead
N with side effects	Does this N affect external state (URL, storage, clipboard)?	Add a store for the external state

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Chunking

Chunking collapses a subsystem into a single node in the main diagram, with details shown separately. Use chunking to manage complexity when a section of the breadboard has:

• One wire in (single entry point)
• One wire out (single output)
• Lots of internals between them

When to Chunk

Look for sections where tracing the wiring reveals a "pinch point" — many affordances that funnel through a single input and single output. These are natural boundaries for chunking.

Example: A dynamic-form component receives a form definition, renders many fields (U7a-U7k), validates on change (N26), and emits a single valid$ signal. In the main diagram, this becomes:

text

N24 -->|formDefinition| dynamicForm
dynamicForm -.->|valid$| U8

How to Chunk

1. In the main diagram, replace the subsystem with a single stadium-shaped node:

text

dynamicForm[["CHUNK: dynamic-form"]]

2. Wire to/from the chunk using the boundary signals:

text

N24 -->|formDefinition| dynamicForm
dynamicForm -.->|valid$| U8

3. Create a separate chunk diagram showing the internals with boundary markers:

Rendering diagram...

4. Style chunks distinctly in the main diagram:

text

classDef chunk fill:#b3e5fc,stroke:#0288d1,color:#000,stroke-width:2px
class dynamicForm chunk

Chunk Color Convention

Type	Color	Hex
Chunk node (main diagram)	Light blue	#b3e5fc
Boundary markers (chunk diagram)	Light blue, dashed	#b3e5fc with stroke-dasharray:5 5

Benefits

• Main diagram stays readable — complex subsystems become single nodes
• Detail preserved — chunk diagrams show the internals when needed
• Natural boundaries — chunks often map to reusable components

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Visualization (Mermaid)

The tables are the truth. Mermaid diagrams are optional visualizations for humans.

Basic Structure

Rendering diagram...

Line Conventions

Line Style	Mermaid Syntax	Use
Solid (-->)	A --> B	Wires Out: calls, triggers, writes
Dashed (-.->)	A -.-> B	Returns To: return values, data store reads
Labeled ...	`A -.->	...

Abbreviating Out-of-Scope Flows

When a data flow has intermediate steps that aren't relevant to the breadboard's scope, abbreviate by wiring directly from source to destination with a ... label:

text

S4 -.->|...| U6

This says "data flows from S4 to U6, with intermediate steps omitted." Use this when:

• The flow exists but its internals are out of scope
• You need to show where data originates without detailing the query chain
• The breadboard focuses on one workflow (e.g., editing) but needs to acknowledge another (e.g., viewing)

ID Prefixes

Prefix	Type	Example
P	Places	P1, P2, P3
U	UI affordances	U1, U2, U3
N	Code affordances	N1, N2, N3
S	Data stores	S1, S2, S3

Color Conventions

Type	Color	Hex
Places (subgraphs)	White/transparent	—
UI affordances	Pink	#ffb6c1
Code affordances	Grey	#d3d3d3
Data stores	Lavender	#e6e6fa
Chunks	Light blue	#b3e5fc
Place references	Pink, dashed border	#ffb6c1

text

classDef ui fill:#ffb6c1,stroke:#d87093,color:#000
classDef nonui fill:#d3d3d3,stroke:#808080,color:#000
classDef store fill:#e6e6fa,stroke:#9370db,color:#000
classDef chunk fill:#b3e5fc,stroke:#0288d1,color:#000,stroke-width:2px
classDef placeRef fill:#ffb6c1,stroke:#d87093,stroke-width:2px,stroke-dasharray:5 5

Subgraph Labels and Place IDs

Use the Place ID as the subgraph ID so navigation wiring connects properly:

Rendering diagram...

Type	ID Pattern	Label Pattern	Purpose
Place	P1, P2...	P1: Page Name	A bounded context the user visits
Trigger	—	TRIGGER: Name	An event that kicks off a flow (not navigable)
Component	—	COMPONENT: Name	Reusable UI+logic that appears in multiple places
System	—	SYSTEM: Name	When spanning multiple applications

Key point: The subgraph ID (P1, P2) must match the Place ID from the Places table. This allows navigation wires like N1 --> P2 to connect to the Place boundary.

When spanning multiple systems

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Workflow Step Annotations (Optional)

When breadboarding a specific workflow, you can optionally add numbered step markers to help readers follow the sequence visually. This is useful when:

• The diagram is complex and the workflow path isn't obvious
• You want to guide someone through a specific user journey
• The breadboard will be used as a walkthrough or teaching tool

Format:

Add a Workflow Guide table before the diagram:

markdown

| Step | Action | Where to look |
|------|--------|---------------|
| **1** | Click "Edit" button | U1 → N1 → S1 |
| **2** | Edit mode activates | S1 → N2 → U3 |
| **3** | Click "Add" | U3 → N3 → N8 |

Add step marker nodes in the Mermaid diagram using stadium-shaped nodes:

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Formatting notes:

• Use "1 - ACTION" format (number, space, hyphen, space, action)
• Avoid "1. ACTION" — the period triggers Mermaid's markdown list parser
• Avoid "1) ACTION" — parentheses can also cause parsing issues
• Connect step markers to affordances with dashed lines (-.->)
• Style steps green to distinguish from UI (pink) and Code (grey) affordances

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Slicing a Breadboard

Slicing takes a breadboard and groups its affordances into vertical implementation slices. See Example B below for a complete slicing example.

Input:

• Breadboard (affordance tables with wiring)
• Shape (R + mechanisms) — guides what demos matter

Output:

• Breadboard with affordances assigned to slices V1–V9 (max 9 slices)

What is a Vertical Slice?

A vertical slice is a group of UI and Code affordances that does something demo-able. It cuts through all layers (UI, logic, data) to deliver a working increment.

The opposite is a horizontal slice — doing work on one layer (e.g., "set up all the data models") that isn't clickable from the interface.

The Key Constraint

Every slice must have visible UI that can be demoed. A slice without UI is a horizontal layer, not a vertical slice.

• ✅ "Self-serve Signing Path" (demo: checkout → sign → see signature)
• ❌ "Database Schema" (no demo possible)

Demo-able means:

• Has an entry point (UI interaction or trigger)
• Has an observable output (UI renders, effect occurs)
• Shows meaningful progress toward the R

The shape guides what counts as "meaningful progress" — you're not just grouping affordances arbitrarily, you're grouping them to demonstrate mechanisms working.

Slice Size

• Too small: Only 1-2 UI affordances, no meaningful demo → merge with related slice
• Too big: 15+ affordances or multiple unrelated journeys → split
• Right size: A coherent journey with a clear "watch me do this" demo

Aim for ≤9 slices. If you need more, the shape may be too large for one cycle.

Wires to Future Slices

A slice may contain affordances with Wires Out pointing to affordances in later slices. These wires exist in the breadboard but aren't implemented yet — they're stubs or no-ops until that later slice is built.

This is normal. The breadboard shows the complete system; slicing shows the order of implementation.

Procedure

Step 1: Identify the minimal demo-able increment

Look at your breadboard and shape. Ask: "What's the smallest subset that demonstrates the core mechanism working?"

Usually this is:

• The core data fetch
• Basic rendering
• No search, no pagination, no state persistence yet

This becomes V1.

Step 2: Layer additional capabilities as slices

Look at the mechanisms in your shape. Each slice should demonstrate a mechanism working:

• V2: Search input (demonstrates the search mechanism)
• V3: Pagination/infinite scroll (demonstrates the pagination mechanism)
• V4: URL state persistence (demonstrates the state preservation mechanism)
• etc.

Max 9 slices. If you have more, combine related mechanisms. Features that don't make sense alone should be in the same slice.

Step 3: Assign affordances to slices

Go through every affordance and assign it to the slice where it's first needed to demo that slice's mechanism:

Slice	Mechanism	Affordances
V1	Core display	U2, U3, N3, N4, N5, N6, N7
V2	Search	U1, N1, N2
V3	Pagination	U10, N11, N12, N13

Some affordances may have Wires Out to later slices — that's fine. They're implemented in their assigned slice; the wires just don't do anything yet.

Step 4: Create per-slice affordance tables

For each slice, extract just the affordances being added:

V2: Search Works

#	Component	Affordance	Control	Wires Out	Returns To
U1	search-detail	search input	type	→ N1	—
N1	search-detail	activeQuery.next()	call	→ N2	—
N2	search-detail	activeQuery subscription	observe	→ N3	—

Step 5: Write a demo statement for each slice

Each slice needs a concrete demo that shows its mechanism working toward the R:

• V1: "Widget shows real data from the API"
• V2: "Type 'dharma', results filter live"
• V3: "Scroll down, more items load"

The demo should be something you can show a stakeholder that demonstrates progress.

Visualizing Slices in Mermaid

Show the complete breadboard in every slice diagram, but use styling to distinguish scope:

Category	Style	Description
This slice	Bright color	Affordances being added
Already built	Solid grey	Previous slices
Future	Transparent, dashed border	Not yet built

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This lets stakeholders see:

• What's being built now (highlighted)
• What already exists (grey)
• What's coming later (faded)

Slice Summary Format

#	Slice	Mechanism	Demo
V1	Widget with real data	F1, F4, F6	"Widget shows letters from API"
V2	Search works	F3	"Type to filter results"
V3	Infinite scroll	F5	"Scroll down, more load"
V4	URL state	F2	"Refresh preserves search"

The Mechanism column references parts from the shape, showing which mechanisms each slice demonstrates.

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Examples

Example A: Mapping an Existing System

This example shows breadboarding an existing system to understand how data flows through multiple entry points.

Input

Workflow to understand: "How is admin_organisation_countries modified and read downstream? There are multiple entry points: manual edit, checkbox toggle, and batch job."

Output

UI Affordances

#	Component	Affordance	Control	Wires Out	Returns To
U1	SSO Admin	role_profiles checkboxes	render	—	—
U2	SSO Admin	"Country Admin" checkbox	click	toggles selection	—
U3	SSO Admin	admin_countries filter_horizontal	render	—	—
U4	SSO Admin	Available countries list	render	—	—
U5	SSO Admin	Selected countries list	render	—	—
U6	SSO Admin	Add → / Remove ←	click	modifies selection	—
U7	SSO Admin	Save button	click	→ N3	—
U20	DWConnect	"Country admins" section	render	—	—
U21	(unknown)	System email "From" field	render	—	—

Code Affordances

#	Component	Affordance	Control	Wires Out	Returns To
N1	sso/accounts/admin	get_fieldsets()	call	→ U3 (conditional)	—
N2	sso/accounts/models	get_administrable_user_countries()	call	—	→ U4
N3	sso/accounts/admin	save_form()	call	→ N4, → N5	—
N4	Django Admin	Form M2M save	call	→ S2	—
N5	sso/forms/mixins	_update_user_m2m()	call	→ S1, → N6	—
N6	sso/signals	user_m2m_field_updated signal	signal	→ N10	—
N7	CLI/Scheduler	manage.py dwbn_cleanup	invoke	→ N15	—
N10	sso-dwbn-theme	dwbn_user_m2m_field_updated()	receive	→ N11	—
N11	sso-dwbn-theme	dwbn_user_m2m_field_updated_task()	call	→ N12	—
N12	sso-dwbn-theme	Country Admin added AND zero admin countries?	conditional	→ N20	—
N15	sso-dwbn-theme	admin_changes()	call	→ N16	—
N16	sso-dwbn-theme	For each Country Admin: home center country missing?	loop	→ N20	—
N20	sso-dwbn-theme	Get home center's country	call	→ N21	—
N21	sso-dwbn-theme	admin_organisation_countries.add()	call	→ S2	—
N22	sso-dwbn-theme	update_last_modified()	call	—	—
N30	dwconnect2-backend	findCenterAdmins()	call	—	→ U20
N31	sso/api	get_object_data()	call	—	→ external

Data Stores

#	Store	Description
S1	role_profiles	M2M: which role profiles a user has
S2	admin_organisation_countries	M2M: which countries a user administers
S3	organisations	User's home center(s)

Mermaid Diagram

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Example B: Designing from Shaped Parts

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Part 1: Shaping Context (Input to Breadboarding)

This section shows what comes FROM shaping — the requirements, existing patterns identified, and sketched parts. This is the INPUT that breadboarding receives.

Note: This example uses shaping terminology. In shaping, you define requirements (Rs), identify existing patterns to reuse, and sketch a solution as parts/mechanisms. Breadboarding takes this shaped solution and details out the concrete affordances and wiring.

The R (Requirements)

ID	Requirement
R0	Make content searchable from the index page
R2	Navigate back to pagination state when returning from detail
R3	Navigate back to search state when returning from detail
R4	Search/pagination state survives page refresh
R5	Browser back button restores previous search/pagination state
R9	Search should debounce input (not fire on every keystroke)
R10	Search should require minimum 3 characters
R11	Loading and empty states should provide user feedback

Existing System with Reusable Patterns (S-CUR)

The app already has a global search page that implements most of these Rs. During shaping, it was documented at the parts/mechanism level:

Part	Mechanism
S-CUR1	URL state & initialization
S-CUR1.1	Router queryParams observable provides {q, category}
S-CUR1.2	initializeState(params) sets query and category from URL
S-CUR1.3	On page load, triggers initial search from URL state
S-CUR2	Search input
S-CUR2.1	Search input binds to activeQuery BehaviorSubject
S-CUR2.2	activeQuery subscription with 90ms debounce
S-CUR2.3	Min 3 chars triggers performNewSearch()
S-CUR3	Data fetching
S-CUR3.1	performNewSearch() sets loading state, calls search service
S-CUR3.2	Search service builds Typesense filter, calls rawSearch()
S-CUR3.3	rawSearch() queries Typesense, returns {found, hits}
S-CUR3.4	Results written to detailResult data store
S-CUR4	Pagination
S-CUR4.1	Scroll-to-bottom triggers appendNextPage() via intercomService
S-CUR4.2	appendNextPage() increments page, calls search
S-CUR4.3	New hits concatenated to existing hits
S-CUR4.4	sendMessage() re-arms scroll detection
S-CUR5	Rendering
S-CUR5.1	cdr.detectChanges() triggers template re-evaluation
S-CUR5.2	Loading spinner, "no results", result count based on store
S-CUR5.3	*ngFor renders tiles for each hit
S-CUR5.4	Tile click navigates to detail page

Sketched Solution: Parts that Adapt S-CUR

The new solution's parts explicitly reference which S-CUR patterns they adapt:

Part	Mechanism	Adapts
F1	Create widget (component, def, register)	—
F2	URL state & initialization (read ?q=, restore on load)	S-CUR1
F3	Search input (debounce, min 3 chars, triggers search)	S-CUR2
F4	Data fetching (rawSearch() with filter)	S-CUR3
F5	Pagination (scroll-to-bottom, append pages, re-arm)	S-CUR4
F6	Rendering (loading, empty, results list, rows)	S-CUR5

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Part 2: Breadboarding (Transform Parts → Affordances)

This is where breadboarding happens. The shaped parts become concrete affordances with explicit wiring. The output is the affordance tables and diagram.

UI Affordances

#	Component	Affordance	Control	Wires Out	Returns To
U1	letter-browser	search input	type	→ N1	—
U2	letter-browser	loading spinner	render	—	—
U3	letter-browser	no results msg	render	—	—
U4	letter-browser	result count	render	—	—
U5	letter-browser	results list	render	→ U6, U7, U8, U9	—
U6	letter-row	row click	click	→ LD	—
U7	letter-row	date	render	—	—
U8	letter-row	subject	render	—	—
U9	letter-row	teaser	render	—	—
U10	letter-browser	scroll	scroll	→ N11	—
U11	browser	back button	click	→ N9	—
U12	letter-browser	"See all X results"	click	→ LP	—
LD	—	Letter Detail	place	—	—
LP	—	Full Page	place	—	—

Code Affordances

#	Component	Affordance	Control	Wires Out	Returns To
N1	letter-browser	activeQuery.next()	call	→ N2	→ U12
N2	letter-browser	activeQuery subscription	observe	→ N3	—
N3	letter-browser	performSearch()	call	→ N4, → N6, → N7, → N8	—
N4	typesense.service	rawSearch()	call	—	→ N3, → N12
N5	letter-browser	parentId (config)	config	—	→ N4
N6	letter-browser	loading store	write	—	→ N8
N7	letter-browser	detailResult store	write	—	→ N8, → N16
N8	letter-browser	detectChanges()	call	→ U2, → U3, → U4, → U5	—
N9	browser	URL ?q=	read	→ N10	—
N10	letter-browser	initializeState()	call	→ N1, → N3	—
N11	intercom.service	scroll subject	observe	→ N12	—
N12	letter-browser	appendNextPage()	call	→ N4, → N7, → N8, → N13, → N14	—
N13	intercom.service	sendMessage()	call	→ N11	—
N14	router	navigate()	call	—	→ N9
N15	letter-browser	if !compact subscribe	conditional	→ N11	—
N16	letter-browser	if truncated show link	conditional	→ U12	—
N17	letter-browser	compact (config)	config	—	→ N4, → N15, → N16
N18	letter-browser	fullPageRoute (config)	config	—	→ U12

Mermaid Diagram

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Slicing the Breadboard

With the full breadboard complete, slice it into vertical increments. Each slice demonstrates a mechanism working:

Slice Summary

#	Slice	Mechanism	Affordances	Demo
V1	Widget with real data	F1, F4, F6	U2-U9, N3-N8, LD	"Widget shows real data"
V2	Search works	F3	U1, N1, N2	"Type 'dharma', results filter"
V3	Infinite scroll	F5	U10, N11-N13	"Scroll down, more load"
V4	URL state	F2	U11, N9, N10, N14	"Refresh preserves search"
V5	Compact mode	—	U12, N15-N18, LP	"Shows 'See all' link"

Slice Diagram

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