RiffGym

Anki for Musicians - A spaced repetition practice tool for guitarists.

RiffGym helps intermediate/advanced guitarists improve technique through progressive speed training. Unlike traditional SRS apps that test memory, RiffGym tests physical proficiency by automatically increasing target BPM when users demonstrate mastery.

Features

Implemented:

• Deck Management: Create and organize riffs into decks (e.g., "Sweeping", "Legato").
• Quick Capture: Fast audio recording to capture ideas or create practice cards.
• Audio Player: Gapless looping, speed control (pitch-preserving), and seeking.
• Metronome: Independent metronome that can run simultaneously with audio playback.
• Practice Mode:
  • SM-2 spaced repetition algorithm for intelligent scheduling.
  • 4-button grading system (Again/Hard/Good/Easy).
  • Auto-Increment BPM based on performance rating.
  • Visual Speedometer with Goal vs Current BPM.
• Smart Audio Tools:
  • Audio cropping (trim start/end).
  • Audio muting (play along with just metronome).
• Rich Media: Add images (tabs/charts) to cards.

Planned:

• BPM History Charts.
• Hands-Free Practice Mode.
• Backup/Export.

Tech Stack

• Flutter (via FVM)
• Dart
• Riverpod - State management
• Drift - Type-safe SQLite database
• just_audio - Advanced audio playback
• record - Cross-platform audio recording

Getting Started

Prerequisites

• FVM (Flutter Version Management)
• Android Studio, Xcode, or VS Code with Flutter extensions

Installation

# Install dependencies
just deps

# Generate code (Riverpod providers, Drift database)
just gen

# Run the app
just run

Development

Available Commands

Command	Description
just run	Launch app on connected device
just test	Run all tests (Unit & Widget)
just test-integration	Run integration tests
just test-coverage	Run tests with coverage
just analyze	Static code analysis
just gen	Generate code (build_runner)
just gen-watch	Watch mode for code generation
just fmt	Format code
just clean	Delete build artifacts
just rebuild	Full rebuild (clean + deps + gen)

Project Structure

lib/
├── main.dart
└── src/
    ├── app.dart                 # App entry point
    ├── core/
    │   ├── database/            # Drift SQLite layer
    │   ├── srs/                 # SM-2 algorithm
    │   └── theme/               # App theme & UI styles
    └── features/
        ├── audio/               # Audio player & metronome logic
        ├── capture/             # Audio recording features
        ├── decks/               # Deck & Card management
        └── practice/            # Practice session UI & logic

Testing

just test

Tests cover:

• SM-2 spaced repetition algorithm
• Audio player & Metronome services
• Widget rendering & UI interactions
• Database migrations & queries

Integration Testing

To run integration tests, you need a connected device or a running simulator/emulator.

# Run all integration tests
just test-integration

# Run a specific integration test
fvm flutter test integration_test/app_test.dart

Integration tests are located in the integration_test/ directory.

How It Works

1. Record a reference audio of a riff at your target tempo
2. Practice along with looped playback
3. Rate your performance (Fail/Hard/Good/Easy)
4. Progress - the app schedules reviews using SM-2 and increases BPM when you're ready

The core innovation: combining spaced repetition scheduling with progressive overload (speed increases) for deliberate practice.