Speedster

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Speedster is a native SwiftUI app for timing Rubik's cube solves. There are no accounts, no ads and no clutter. You get a big monospaced clock, a fresh scramble for every attempt, instant feedback on how you did, and a chart that shows whether you are actually getting faster.

✨ Features

⏱️ Timer

• Tap anywhere to start. The whole screen is the button.
• 5-second countdown before the clock starts, so you have time to get your hands on the cube. Tap during the countdown to cancel it; nothing is saved.
• Audible start cue. A short system "tock" plays when timing begins.
• Millisecond display. Times show as s.mmm, or m:ss.mmm once you pass a minute.
• 25-move scrambles in standard notation (U D F B L R, with ' and 2), shown under the timer between solves. A new one is generated after every solve.

🟢🔴 Instant feedback

When you stop the clock, the result stays on screen and is compared against your Avg 5 from before that solve:

• Green, with a ↓ arrow and "x.xxxs faster", if you beat it
• Red, with a ↑ arrow and "x.xxxs slower", if you didn't

Tap again to clear the result and get the next scramble.

📈 Progression

A second tab tracks your history:

• Summary cards: Total Solves, Best Time and Avg 5
• Trend chart (Swift Charts): individual solve times while you have fewer than 5 solves, then a rolling 5-solve average line once you have enough data
• Calendar browser: pick any day on a graphical date picker to list that day's solves, newest first, with time of day and result
• Cleanup: long-press a solve to delete it, or use Delete all data. Both ask for confirmation first.

🎨 Design

• Black background with orange-gradient accents, always in dark mode
• Universal app for iPhone and iPad, in portrait and landscape

🧠 How it works

The timer screen is a small state machine in TimerView.swift, driven entirely by taps:

stateDiagram-v2
    [*] --> Idle
    Idle --> Countdown: tap
    Countdown --> Idle: tap (cancel, nothing saved)
    Countdown --> Running: 5 s elapsed, play start sound
    Running --> ShowingResult: tap (solve saved)
    ShowingResult --> Idle: tap (new scramble)

• Timing: the clock records a start Date and recomputes elapsed time from it every 10 ms. Because the time is measured against that start point rather than by adding up ticks, a late timer tick never makes the result drift.
• Scrambles: moves are picked at random from the six faces. The same face is never turned twice in a row, and a face is never followed by its opposite (U/D, F/B, L/R).
• Averages:
  • Avg 5 is the plain mean of your 5 most recent solves.
  • Avg All (on the timer screen) is the mean of every solve.
  • Neither one drops the best and worst times the way a WCA-style ao5 does.
• Storage: each solve is a Core Data Solve entity (timestamp, durationMillis), stored locally on the device by NSPersistentContainer in Persistence.swift. SwiftUI @FetchRequest keeps both tabs up to date automatically.

🚀 Build & run

Requirements

• Xcode 26.1 or later (the project was created with Xcode 26.1)
• iOS 26.1+ simulator or device
• No third-party dependencies. Only SwiftUI, Swift Charts, Core Data and AVFoundation are used.

Steps

git clone https://github.com/melucasleite/speedster.git
cd speedster
open speedster.xcodeproj

1. Select the speedster scheme and an iPhone or iPad simulator.
2. To run on a physical device, choose your own team under Signing & Capabilities. You may also need to change the bundle identifier (impulse.codes.speedster).
3. Press ⌘R.

🗂️ Project structure

speedster/
├── speedsterApp.swift        # App entry point; injects the Core Data context
├── ContentView.swift         # Tab bar: Timer + Progression
├── TimerView.swift           # Timer state machine, scrambles, averages, result feedback
├── ProgressionView.swift     # Stats cards, Swift Charts trend, calendar, deletion
├── SpeedsterTheme.swift      # Colors, orange/green/red gradients, typography
├── Persistence.swift         # NSPersistentContainer + in-memory preview data
├── speedster.xcdatamodeld/   # Core Data model (Solve entity)
└── Assets.xcassets/          # App icon
speedsterTests/               # Unit test target (Swift Testing)
speedsterUITests/             # UI test target (XCTest)

👤 Author

Built by Lucas Leite.