Prototype and present design work across three tiers — fake-it (Keynote Magic Move), real code (SwiftUI as a design tool), and agents (collaborators, never designers). Use when validating an idea before building, exploring or converging on UI variants, planning feedback sessions, or structuring a review or pitch. Triggers: prototype, fake it, Magic Move, SwiftUI prototype, tuning panel, design variants, converge on a look, present design work.
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Prototype and present design work across three tiers — fake-it (Keynote Magic Move), real code (SwiftUI as a design tool), and agents (collaborators, never designers). Use when validating an idea before building, exploring or converging on UI variants, planning feedback sessions, or structuring a review or pitch. Triggers: prototype, fake it, Magic Move, SwiftUI prototype, tuning panel, design variants, converge on a look, present design work.
Design Prototyping & Presenting
Sources:references/sources.md — 6 WWDC sessions + 2 ADA articles + Config, Dive Club, and field sources.
Park weak eval/prototype standards in coverage-gaps.md until they have stable evidence, fixtures, and accepted examples.
The trap is idea → build → disappointment. "The more prototypes we can put between your idea and your application, the better the result." The mantra: "Make fake apps, show people, and learn from their feedback. And do that over and over again until the experience of your app feels great." Prototype to test ideas (build the right thing) and to get new ideas. (Using prototypes as eval fixtures for agents/skills: see the eval-fixtures section after the core loop.)
Choose the tier first
Three questions before making anything: What needs to be more real? (the one thing you're testing) · What can we fake? (everything else) · Where will they use it? (test on-device, in context).
The ladder: fake-it for concept validation; SwiftUI prototypes for feel, real data, and demos; agents to drive the code tier wide and fast. ⚠️ 2023 supersedes the older "never real code" absolute — SwiftUI "lowers the floor for simple tasks and raises the ceiling" (non-engineer Maps designers); the hack-it ethic survives: prototype code needn't be good code.
Routing rules:
The quadrant (Ridd): x-axis = size of the work (quick P3 fix ↔ zero-to-one ambiguous idea); y-axis = how much of the material already exists in production. Small+existing → in-codebase agent; big+blank → canvas/AI prototyping tools (names rotate; the axes are durable). The trap: "trying to rebuild production inside of an AI prototyping tool that doesn't sit on top of your production codebase."
First-diamond rule (Ridd + Steven Haney): "if I am operating in that first diamond there is no way that I'm going to start in [Claude] code" — divergence stays in cheap media; agents enter when converging. "Designs being disposable is like a good thing."
One concern per artifact — a "breakable toy" (Josh Puckett): name the single question the artifact answers; go only as far as needed — sometimes "dangerously close to a wireframe" is correct. One artifact (or prompt) solving everything produces myopic rabbit holes. Fidelity is set by audience + the decision at hand.
Concept car → crash test → flag (Linear): a bold concept makes the future easier to say yes to, but it earns implementation only after focused crash tests. Test the environment (native shells, browser, platform controls), appearance (light/dark/custom themes, contrast), and hierarchy (every major view type and state). Then ship behind a feature flag with old/new toggles so dogfood feedback compares reality, not memory.
Medium-matching (Rafa Conde; Cursor school): pick by data needs — "I need real data… it is just faster to create a new branch of the main app." Walks + bullet lists for conceptual problems; Figma for exact pixels; code when states and AI behavior matter — AI interactions "you just can't fake" in mocks.
Static mocks are hunches, not handoffs (Stamatiou "Craft" 2022; Castilho): "It's not until I start building and really using it that I get more signal"; motion and interaction feel are never prototyped in Figma — always tuned in code. Design is "a conversation between design and engineering."
Tier 1 — fake it at the cheapest fidelity that answers the question
Pictures: start with many hand-drawn sketches — "you should not start prototyping from just a single idea." Then Keynote: screenshot a similar app, block areas with shapes, fake the text, photos, and icons. One screen ≈ 10 minutes; defer visual-design decisions; zoom to physical size to check tappability.
Animation: Keynote Magic Move = slides as keyframes. "Any animation you choose is communicating something about the relationship these screens have." Identical shapes avoid cross-fades; stagger list items; duplicate slide 1 as slide 3 for the free reverse. Run it on the phone — taps advance, so it feels interactive.
Interaction: "make pictures move in response to touches, on the device you're prototyping for." Any tool works ("it's about subverting your tools"). Don't engineer it — hack it. Big screenshots dragged by touch deltas fake a scrolling list; an image sequence fakes a keyboard.
The 60-second bar: a working-feeling Keynote timer "in less time than it took you to brush your teeth." Speed buys breadth — many parallel explorations across a diverse team.
Keep exploration loose — structure later (Stamatiou): auto layout / design systems are "the worst thing when you're quickly exploring wildly different concepts"; to break your own tendencies ask "how would [another company] design this?"
Field notes (references/methods.md): prototype at true spatial context (Jae Park; physical tier → hardware-product-design); scaffold, don't script, for collaborators (PBJ); prototype the core loop before the app exists (CapWords); at publishing scale (Vox/Polygon): real content gut-checks everything, embed the front-end dev in exploration, plan polish as an end stage, the decoy mood board, verify production dependencies early.
Team-of-one adaptation (Buley): when you need buy-in as much as answers, "turn any meeting into a design session" — sketch live, invite non-designers to sketch (references/methods.md).
Tier 2 — real code: SwiftUI as a design tool (2023)
Dynamic tools surface what static ones hide: loading states, pressed states, Dynamic Type — "the moment we started making prototypes, they were obvious."
Design how it feels, on device: interactions "give you a sense of how your designs feel, not just how they look" — a too-fast Digital-Crown zoom was fixed by scrubbing sensitivity values live; velocity-aware tuning is the kind of decision only a feel-prototype settles.
Find where designs break: real data and real environments — flat New York routes exposed a Y-axis bug that hilly San Francisco data hid; sunlight drove contrast. "It's important to find out where my designs break."
Build one-off parameterized mini-tools: sliders scrubbing line width/opacity/blend-mode over the live UI — "way more variations than we'd be able to do efficiently in a static design tool."
Demos lead reviews: "When people can hold a demo of your work in their hands, designs explain themselves." And the payoff unique to this tier: "you're not just creating a prototype… you can ship what you design."
Tier 3 — agents driving the code tier (2026)
Coding agents + previews "supercharge the prototyping of key screens and moments" — and the real native code can carry forward. The governing stance: "Do not delegate critical thinking to these tools… think of coding agents as collaborators in your prototyping process," not as designers — "the key piece of the puzzle is your judgment." Five patterns:
Go wide, remix, repeat (exploration): be specific about features and mood, and "most importantly, ask for multiple options" — e.g. 10 variations, each as its own named #Preview; then remix the promising ones. Make options structurally different concepts, not variants (Josh Puckett); current tooling is depth-biased, so budget divergence deliberately (Ian Silber). Range moves: references/agents-field-notes.md.
Agent as fake user (lived-in content): have the agent "play the role of somebody using your app" — but you think through edge cases (empty states, unbounded growth); keep sample content plausible and in its own reusable file. Realistic content surfaces missing blank-slate UI and layout breaks.
Agent-built tuning panels (key moments): the parameterized mini-tool, generated on demand — "ask for the animation to be broken into phases… a shared vocabulary"; panel side by side with the UI. "Make a tuning panel, shorten the feedback loop, and get to what feels optimal." Converging field versions (Kyle Santos's effect studios, Kris Puckett's copy-values-back round-trip, MDS's tool-making reflex, Josh Puckett's live tuning + iterations grid): references/agents-field-notes.md.
Independent judge in a fresh context (evaluation): don't let the generating agent grade its own output — it's anchored on its own choices. Spawn a separate judge with its own context window, loaded only with explicit criteria ("create an independent judge with its own context window to evaluate your output" — Carlos Montoya, Dropbox, X 2026; used "to raise the pixel craft of frontier models"). Loadout from this corpus: design-principles facets + critique mechanics, design-craft checklists, design-craft depth spectrum — score against those, not vibes. Same model is fine, same context is not. Full notes incl. the MDS/Shift Nudge MCP: references/agents-field-notes.md.
Converge by walking the design tree (convergence): after going wide, render 3–5 structurally different variants behind a floating live switcher inside the app — "a throwaway route on its own is a vacuum: every variant looks fine in isolation" (Pocock /prototype; Will Ness's grilling-frontend variant, 2026). Then rounds of pick-favorites-plus-verdict, each round re-prototyping the current question one level deeper: overall design → component groups → individual components — until the feature is designed in detail. Switcher mechanics, caps, capture rules: references/agents-field-notes.md.
Prototype with the full dataset and in the target production stack (Evil Martians) so handoff is copy-paste — "my technical knowledge, multiplied by AI"; AI removes friction, not judgment.
Mock-to-code: diff against the mock element-by-element (Stamatiou vs Claude Design 2026, first pass "65/100") — the checklist below — before iterating on anything else.
The Cursor school endpoint (Ryo Lu; Jin Park/Notion; Catherine/Ramp): designers ship code instead of mocks — "Mocks and renders show possibilities. Prototypes show reality." And "the difference between slop and soulful products is iteration and taste. Most people stop at the first output, rather than using it to begin."
Shared lightweight prototyping environments: keep a baby-cursor — never ideate in the gigantic slow codebase (Ryo Lu); Notion's 80/20 shared playground, fidelity per-question (Brian Lovin); Ramp's three-tier fidelity ladder (vibes stack → real-component sandbox → real repo); Stripe's Protodash prototypes inside the surrounding product — "no product is like ever felt by your user in isolation" (Katie Dill).
Visual prompting: the screenshot or sketch is the prompt (Steve Ruiz, Make Real — iterate by drawing arrows on the output; paste a reference image); storyboard-as-prompt, but don't dial fidelity in Figma — "Figma's a lie. It's not your actual code base" (Josh Puckett).
MDS workflow: 85%-in-Figma, finish in code — hover states designed only in code ("it's all about how it feels"); components only when they pay — too many too early constrains creativity.
Jigs (Geoffrey Litt): disposable one-project tools an agent makes economical. Start from anywhere (Luis Ouriach): "the canvas is very important for ideation… but the browser is where we commit" — "not faster, but further."
Prototype → production seam: render the idea, don't ship it (Katarina Batina — "Just render the whole idea and then use that as the thing you talk to engineering with"; not shippable ≠ failure). Editable stakeholder prototypes, hedged variants, the playground-to-production one-shot (Andy Madrick). The two-system tax (→ working-with-ai (agentic-coding)): past concept validation, prototype in the real repo.
Perishable layer: Xcode-agents UI specifics (Xcode 26; WWDC26-259) and 2025–26 tool names. Durable layer: the prompt patterns and collaborator-not-designer stance.
Show — structured, on device, in context
Show the people the app is for ("if your app isn't for engineers, go find some people who are not engineers"), in the real context. A recurring representative outsider works — Stollenmayer's "mom test": voluntary enjoyment, not polite completion.
Personalize the sandbox when personalization is the point (Soleio Cuervo, First Round, 2014): a generic screenshot cannot test a personalized experience. Pull in the stakeholder's/user's own graph data or realistic personal context so they feel what the product would actually know, infer, and change. The feedback quality jumps when the prototype is experienced through a personal lens.
During: Do you know how to do X? · Is it easy? · How can we make this better? Have theories beforehand; look for evidence for or against. "Don't argue, defend or dismiss. You're not there to debate — you're there to get information."
Review stance for context-rich prototypes (Katie Dill): "Please don't present. Please don't pitch… I just want to see it like a user."
Avoid the prototype drop (Buley): don't release prototypes "into the wild" for async feedback — review synchronously, invite the team to observe (references/methods.md).
When words fail on visual nits, draw a caricature (type-designer technique, 2018-801): exaggerate the feature until others see the toned-down real one — find "the joint gaze" (references/methods.md).
Make shareable, reactable artifacts: "Make an ad, right? Sell this idea" — under 10 minutes, shot in a hand (Rafa Conde); chase heat with async video (Katarina Batina); Ian Silber's PD-whip channel bans raw musings — "It's got to be a prototype or video."
Learn — then go around again
After: What's working? · What's not? · What other ideas does this give us? Collect open questions — "the goal isn't to answer all of those questions, but to know what you don't know." Triage: some ideas survive; most get recombined; "a few things won't work at all, and it is great when that happens" (the grid-view "concept sucked" — killed by a drawing, not a build).
Budget the loop so insights land: "always leave adequate time after gathering new insights to not only design refinements, but build them and live with them for a bit first" — research arriving just before ship buys only a compromise (Stamatiou, "Craft").
Soleio's reality-collision rule (Julie Zhuo interview, 2026; Design Buddies recap, 2025): the Like button was one of many shipped experiments, while Dropbox Carousel paid for hiding from users too long — full camera-roll access collided with storage-quota anxiety late. Treat speed as a way to collide with reality sooner, not a license to ship junk. If the scary assumption is "will people trust this?", prototype the trust moment first and get it in front of real users before polishing the rest.
Test social mechanics in the graph, not in isolation (Soleio, Design MBA + PBS): the Like button sat in "product purgatory" on the fear it "would cannibalize commenting" — "our intuition was just dead wrong." The unblocking experiment: "we chose two pairs of networks where there was high friend density," ship vs. control countries — likes increased commenting ("a social lubricant"). Pick test cells where network effects can appear; measure the downstream behavior the feature might suppress or unlock. More: references/soleio-field-notes.md.
From the prototyping team's 2022 Q&A (references/methods.md): no hole-in-ones ("If we're not getting feedback on something, we're just not showing it to the right people"); keep multiple directions alive; phrase feedback as the experience, not taste; and the trap — "we sometimes get caught up in trying for a perfectly polished prototype" — always remember the question the prototype exists to answer.
Prototypes as eval fixtures (skill-lab loop)
When a prototype becomes an eval fixture for an agent or skill, keep the fixture hermetic and separate retrieval from application: expected skill loaded, references used, before/after artifact, rubric, hidden holdout expectation, and human preference reason. Route packaging mechanics to creating-skills; use this skill for the prototype question and evidence loop.
Skill-lab loop for design rules (Jaytel Taste repo, 2026): when evaluating a generated design skill, keep the current skill as a baseline candidate, generate bounded mutation hypotheses, render each candidate against the same prompt in self-contained HTML, collect a human preference vote plus reason, then update the skill from the preference history. The baseline-as-control matters: otherwise every round looks like progress because it is merely different.
Compare skill effects, not single outputs (Jaytel Taste demo): run the same prompt through base model, broad design skill, and the specific taste skill before trusting a new design skill. The dashboard/chat comparisons exposed a useful difference: a broad frontend skill can make output more stylish while the reference-derived skill makes it more specifically constrained. Judge whether the skill moves the output toward the intended corpus, not merely whether the screen looks better.
Keep eval artifacts hermetic (Jaytel Skill Lab): generated candidates should render in an iframe without external scripts, fonts, images, or stylesheets when the test is about the skill, not network luck or asset taste. This makes side-by-side preference less noisy and easier to replay.
Prototypes win arguments — "moving away from slide decks, moving away from PRDs" (Ron Goldin, whose same-day counter-demo overturned a VP "can't be done"; Duolingo as policy: come with a prototype, "MVP is outlawed" — ship V1s). The strongest moves: the Spectrum technique (Cheechee Lin) — align the room on the problem, why it matters, and a spectrum of solutions far apart enough to force a clear conversation ("You just need one that moves the room"); and prototype in engineering's stack when eng says "not possible," against real data and real models. Reference adds: vision-prototype recipe, lookbook pitch, spreadsheet chatbot, concept-as-its-own-ad.
Presenting design work — the ten rules (2018)
"Design is hard but design presentations are way harder" — present badly and the ideas die. Texture: references/methods.md.
Know your objectives — imagine success, work backwards; state goals and needed questions up front.
Embrace feedback — "there is no failure, only feedback"; an unworkable offered solution usually wraps a valid problem — clarify it; never pretend to understand unclear feedback.
Seek advice — sense-check the deck; full practice run; "do not deliver it blind."
Use your own voice — genuine, opinionated ("you are the expert here"), never arrogant.
Respect your audience — agenda, recap, their prior feedback visibly integrated, no working files.
Make it relatable — first-person narrative, not users as "a distant third party"; a prototype demo beats a flow diagram.
Engage in dialogue — design for the aha moment; "do not deliver a monologue."
Explain why — "define each problem in a single sentence" and get agreement; evidence, never "because I like it."
Storytelling — "people won't remember your slides. They'll remember how your story made them feel." Contrast today with the better future (Duarte).
Keep it simple — "keep the main thing the main thing"; summarize.
Pitch mechanics (Wojtek Dziedzic, Config 2025)
"Ideas do not matter… it's how we sell it." Attention cap ~20 minutes; one through line; three-beat arcs — PSB (Problem → Solution → Benefit) for logic, SIA (Story → Insight → Action) for emotion; open with a hook, never data. Slide rules and Hische's critique-ruiner exercise: references/pitch-and-influence.md.
"Make the right thing, then make the thing right" — words/low-fi while finding the right thing, then one prototype that feels exactly like the end product, just for one day. Interpret feedback, don't transcribe it; ignore "I think I would use it" — look for "a core set of people who truly love it… it would be very painful for them if it was taken away." Medium-to-audience matching, research mechanics, humility cases: references/pitch-and-influence.md.
Sharing explorations (Femke van Schoonhoven, Uber Eats)
Four-part structure: context → concepts → rationale → always a recommendation. Match fidelity to audience; show the MVP next to the future vision (pre-answers "why not X"); name your concepts; lay flows next to P0/P1/P2 requirements for async readers; keep a personal sandbox page. The business case around the pitch → design-org-influence.
Checklist
Sketched many ideas before prototyping one?
Faking everything except the one thing under test; testing on-device, in context?
Right tier: fake-it for concept questions, SwiftUI feel-prototype for interaction/data/demo questions?
Agent output diffed against the mock — typography, colors, radii, spacing, missing states, gradient scale?
Tested with real (ugly, edge-case) data and in real environments — found where it breaks?
Feedback sessions use the question sets; no defending or debating?
Solo/low-support context: meeting made participatory, not a big reveal or async prototype drop?
Open questions logged; ideas triaged (keep / recombine / kill) before the next loop?
Presentation: objectives + problem statements up front, story over slides, dialogue over monologue?
(Eval fixtures) If testing a new visual/design skill, compared base vs broad-skill vs specific-skill output under the same prompt?
(Eval fixtures) If iterating a skill, kept the old skill as a baseline candidate and recorded the human preference reason?
user-research — when the question is discovery/validation rather than artifact feedback: method selection, interviewing craft, screeners; concept-reaction sessions use its neutral-presentation rules with this skill's artifacts.
design-org-influence — the business case, stakeholder politics, and objection handling around a pitch; this skill owns the artifact and the session.
client-work (client-engagements) — presenting/prototyping inside a client engagement (feedback training, session health); this skill owns the artifact and session craft.
swiftui (touch-interaction-design) — "the interactive demo is worth a million static designs" is this skill in action; prototype interactions with these methods, judge them with that skill.
design-principles — supplies what to evaluate against; this skill supplies the loop that produces evidence.
hardware-product-design — the physical tier: non-functional mockups, cabled rigs, test jigs, foam core at true viewing distance.
feature-discoverability / swiftui (sound-design) — both close with "prototype and test"; this is the how.
figma:figma-use / paper-desktop:design-to-code — external plugin skills (not in this repo; use if installed): modern tooling for the same make-fast, tool-agnostic ethic ("subvert your tools").
swiftui (swiftui-layout) / swiftui (swiftui-animation) — the building blocks for the real-code tier; this skill says why and when to prototype in SwiftUI, those say how.
design-craft — the quality-practice loop; its prototyping moves (breakable toy, live tuning, iterations grid) are folded in above. Route "is it good enough" / how-far-to-push to its depth-spectrum heuristic there.
working-with-ai (agentic-coding) — when prototyping graduates to production engineering with agents (designer shipping production code, encoding decisions as rules); owns the two-system tax case study.
