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En Croissant includes a powerful repertoire training system that helps you memorize and practice your opening lines using scientifically-proven spaced repetition algorithms.

Building a repertoire

Create your opening repertoire by building a tree of moves in the board editor:
1

Create opening file

Start a new analysis tab or open an existing PGN file with your repertoire lines.
2

Add moves to your tree

Play through your opening variations. Each branch represents a different line in your repertoire.
3

Set orientation

In the file headers, set your color (white or black) to determine which moves you’ll practice.
4

Switch to practice panel

Open the practice panel and navigate to the Train tab to begin.

Build tab

The Build tab in the practice panel helps you construct your repertoire:
  • View repertoire structure and statistics
  • See reference database games for positions
  • Identify gaps in your preparation
  • Add new lines based on common responses

Spaced repetition system

En Croissant uses the FSRS (Free Spaced Repetition Scheduler) algorithm powered by the ts-fsrs library. This modern spaced repetition algorithm optimizes your practice sessions:

How it works

  1. New positions: Added to your deck when you build your repertoire
  2. Practice sessions: You try to recall the correct move for each position
  3. Quality rating: After each correct move, rate how difficult it was
  4. Scheduling: The algorithm schedules the next review based on your rating

Rating system

After making the correct move, rate the difficulty:
Keyboard: 1You forgot the move or it was very difficult. The position will be shown again very soon.
Each rating shows the next review time so you can see how your rating affects the schedule.

Training workflow

The practice panel provides a complete training experience:

Train tab

Progress tracking

View your repertoire statistics:
  • Practiced: Positions you’ve seen at least once (blue)
  • Due: Positions scheduled for review now (yellow)
  • Unseen: New positions not yet practiced (gray)
  • Progress bar: Visual representation of your repertoire mastery

Session statistics

Track your current practice session:
  • Correct: Moves you got right
  • Incorrect: Moves you missed
  • Accuracy: Percentage of correct moves in the session
  • Streak: Current consecutive correct moves
Try to maintain a high streak by consistently practicing. The flame icon shows your current streak!

Practice states

1

Start practice

Click Start Practice to begin. The button shows how many positions are due or unseen.
2

Make your move

The position loads with opponent’s move already played. Make your prepared move on the board.
3

Correct move

If correct, rate the difficulty (1-4). If incorrect, the correct move is shown.
4

Next position

The next position loads automatically (or click Next Position if you missed the move).

Incorrect moves

When you make a wrong move:
  • The correct move is displayed
  • You can navigate to see the correct continuation
  • Press Space or click Next Position to continue
  • The position is not added to review schedule (you’ll see it again soon)

Deck synchronization

Your practice deck automatically syncs with changes to your repertoire tree:
  • Added lines: New positions appear in your deck automatically
  • Removed lines: Deleted positions are removed from the deck
  • Modified lines: Changes are reflected with minimal disruption
  • Sync notification: You’ll see a message showing what changed
When you add or remove moves from your repertoire, the deck updates automatically without losing your practice progress.

Advanced features

Viewing all positions

Click Show All to see every position in your deck:
  • Status badge (Unseen, Due, or Practiced)
  • Next review date
  • Move notation
  • Jump directly to any position

Practice logs

Click Show Logs to review your training history:
  • All past reviews with ratings
  • Timestamp for each review
  • Difficulty rating you gave
  • Navigate to positions from logs

Resetting progress

Click Reset to:
  • Clear all practice history
  • Reset all cards to “New” status
  • Start fresh with your repertoire
Resetting progress is permanent and cannot be undone. All your practice history will be lost.

Best practices

  1. Consistent practice: Review due positions daily for best retention
  2. Honest ratings: Rate difficulty accurately for optimal scheduling
  3. Complete repertoire: Add all your lines before starting intensive practice
  4. Regular updates: Add new lines as you expand your repertoire
  5. Review completions: When all positions are practiced, come back when cards are due

When you’re done

When you’ve practiced all due positions, you’ll see:
  • Congratulations message
  • Next review date showing when positions become due again
  • Option to start a new session to review more
The spaced repetition algorithm optimizes review timing. Trust the schedule and review positions when they become due for maximum retention.

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