Hydrolyze Feel Direction Playful V1

User signal 2026-06-20. The user's first request to push Hydrolyze's

feel in a direction beyond the existing VISION.md framing of

"information-rich effortlessness." The verbatim ask: **"Lets work

on micro interaction for the hydrolyze app. haptic feedback,

animations etc. make the app feel playful etc. look at the existing

UI components and aduit them and improve them—go through with a fine

tooth comb, searching for areas on improvement."** (User wrote "aduit"

— preserved verbatim, not auto-corrected.)

The tension being resolved

Hydrolyze's existing VISION.md principle is information-rich effortlessness — a professional tool for swim coaches at 5am with 24 swimmers in the water. The previous design system was deliberately restrained:

• B&W + 20% cyan aesthetic (mostly monochrome, cyan only as accent)
• JetBrains Mono for numerics, system for body
• No motion language at all (only one animation: the cyan flash on

LAP tap)

• Zero haptics
• All interactions were functional, not experiential

The new direction adds a layer the old framing explicitly didn't have: playfulness. This sounds contradictory with "professional tool for 5am pool deck." The resolution:

The principle: playful ≠ gamey. Playful means the app feels like it CARES about the experience. Gamey means the app is a toy. Hydrolyze stays a professional tool; the playfulness is in the responsiveness, not the whimsy.

The audit findings (what was missing)

Before the 2026-06-20 work, the iOS native codebase had:

• Zero haptics across 11 view files. The LAP button — the coach's

primary action, tapped dozens of times per session — had no tactile feedback.

• Only one animation (lapFlashOpacity on LAP, easeOut(0.3s)).
• No press feedback on any button. The 200×200 cyan START

compressed invisibly on tap.

• No row transitions in SessionReviewView or SwimmersListView

— rows popped in.

• No animated tab indicator — the SessionReview filter background

swap was a hard cut.

• No breathing/pulse on idle CTAs — the START button didn't invite

the tap.

The resolution: three foundation utilities

See Hydrolyze Micro Interaction System for the system architecture. Summary:

• Haptics.swift — semantic enum with one vocabulary across the app
• PressFeedbackStyle.swift — ButtonStyle + view modifier
• Animations.swift — shared curves: snap / gentle / springSnappy /

springSoft / breathing

All three are in Hydrolyze/Sources/Lib/. One file per concern. Future iOS work should reach for these instead of constructing ad-hoc haptics, press effects, or animation curves.

Coverage from the 2026-06-20 audit

74 interaction points across 11 files. Per-file breakdown:

Parse-verified all 11 files (zero errors). Did NOT run a real xcodebuild (needs Mac Studio). Did NOT add unit tests.

What's deferred

• State transition animations in TimingView. The `.setup → .ready

→ .running → .finished state machine still does hard swaps on the ZStack. With withAnimation wrapping the state changes plus .transition(.opacity.combined(with: .scale))` on the ZStack children, the transitions could be smooth. Not done in this pass — the per-button work was higher impact. Captured for v1.16+.

• Sound design. Coach is on pool deck. Sound haptics (not yet on

iOS but coming) would be the right escalation. Captured for v2.

• Matched geometry effects. The LAP button → row transition when

a lap is recorded into the review surface would be a satisfying matched-geometry. Not done — would need surface redesign.

• Reduce motion accessibility. The breathing animations should

respect accessibilityReduceMotion and degrade to static. Not yet wired; future accessibility pass.

Direction correction (2026-06-20): warmth through motion, not text

After the v1.16 micro-interaction audit landed, the user gave a sharp direction shift on how to express the "warm" voice the playful direction was already implying: "Let's go with 'warm.' We should try to make it feel welcoming and interactive. We can do this through the UI animations and how the user interacts with the app, rather than focusing on the text components."

The principle: voice in product design is multi-channel. For a pool-deck timing tool (read-by-glance, not read-by-word), the right channel is motion + interaction, not text. The clinical text conventions (HYDROLYZE, REVIEW, LAP, READY, SESSION COMPLETE) STAY — they read cleanly on a pool deck at 5am. The warmth comes from how the app responds, not what it says.

What "warm through motion" looks like in Hydrolyze:

• Spring physics everywhere — all transitions use Animations.springSnappy

or springSoft, never plain easeInOut. The bounce/punch of a spring feels ALIVE.

• Idle invitations — key CTAs (START, Save, Confirm) breathe

gently when idle (the v1.16 START button work; extend pattern).

• Reactive feedback — every tap responds in <16ms with scale-down

+ haptic + color shift, BEFORE the async work. The user knows the tap registered even before the result.

• State transitions — when the app changes state (.setup →

.ready → .running, filter tabs, login modes), the transition is a smooth crossfade with subtle scale. Not a hard cut.

• Row enter/exit — list rows animate in/out with spring

physics. The list feels ALIVE.

• Loading choreography — async work gets phased indicators. The

user sees progress, not "stuck."

• Completion moments — the Tick Mark Celebration Pattern

is the canonical example. No text. Tick mark animation + haptic.

• Empty states — breathe (the v1.16 house-icon breathing

pattern, generalized to all empty states).

See Warmth Through Motion for the full principle, cross-cutting posture generalization (Felt Faction's text-channel warmth vs. Hydrolyze's motion-channel warmth), and the critique of LLM default-to-text behavior on "feel" directives.

Connection to Felt Faction (cross-project)

Per Felt Faction iOS app v2 — replacement direction + chip-counting, Felt Faction already cited "Haptic feedback" as a Hydrolyze pattern to lift. With Hydrolyze now having haptics properly implemented, the patterns in Haptics.swift and PressFeedbackStyle.swift can be ported to the Felt Faction iOS app verbatim — they're pure utility files with no Hydrolyze-specific dependencies.

Felty's voice (Felty) also pairs naturally with haptics: each Felty narration point (loan offer, interest debit, phoenix earned) should have a matching haptic at the iOS layer.

See also

• Hydrolyze — project hub
• Hydrolyze Micro Interaction System — the technical

architecture (3 utilities, design vocabulary, cross-cutting rules)

• Hydrolyze Product Framing — the VISION.md "information-

rich effortlessness" principle being extended, not replaced

• Felt Faction iOS app v2 — replacement direction + chip-counting

— Felt Faction citing Hydrolyze haptic patterns to lift

Source

• 2026-06-20 user signal: "Lets work on micro interaction for the

hydrolyze app. haptic feedback, animations etc. make the app feel playful etc. look at the existing UI components and aduit them and improve them—go through with a fine tooth comb, searching for areas on improvement."

• User's correction (mid-turn): memory should default to gbrain, not

the local memory tool. Captured as preference signal.

• Codebase state: Hydrolyze/Sources/ at the 2026-06-20 audit

baseline. Engine, prediction, and SessionReview v1.14 polish work (commit fef54a1 + slice 1 9db019e) was the prior baseline.

Published and managed by TARS, an AI co-author built on Nathan's gbrain.