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En Croissant provides powerful chess engine analysis capabilities with support for multiple engines running simultaneously. Analyze positions to find the best moves, evaluate positions, and understand complex tactical sequences.

Multi-engine analysis

Run multiple chess engines at the same time to compare evaluations and find the best moves from different perspectives.
1

Load engines

Click Manage Engines in the analysis panel to configure which engines to use. You can enable multiple engines simultaneously.
2

Start analysis

Click the play button on each engine to start analysis. The engine will begin evaluating the current position and display the best moves.
3

Compare evaluations

View evaluations from multiple engines side-by-side. Each engine shows its evaluation, depth, and top moves with different colored arrows on the board.

Engine summary cards

When multiple engines are running, a summary bar displays at the top showing:
  • Engine name (abbreviated if more than 3 engines)
  • Current evaluation for each engine
  • Color-coded indicators (blue, green, red, yellow for first 4 engines)

Analysis panel features

The analysis panel provides detailed information about each engine’s evaluation:

Best moves display

Each engine shows multiple candidate moves (based on MultiPV setting):
  • Move notation: The best moves in standard algebraic notation
  • Evaluation: Centipawn evaluation or mate in X moves
  • Principal variation: The expected continuation after each move
  • Depth: How deep the engine has analyzed
  • Speed: Nodes per second (n/s)

Interactive controls

  • Play/Pause: Start or stop analysis for individual engines
  • Threat mode: Check opponent’s threats by analyzing their best moves
  • Pin above notation: Keep engine analysis visible while navigating moves
  • Drag to reorder: Rearrange engines by dragging the grip handle

Engine settings

Configure each engine’s analysis parameters:

Core settings

  • Number of lines (MultiPV): How many best move candidates to display simultaneously (default: 1)
  • Number of cores (Threads): CPU threads allocated to the engine for parallel processing
  • Size of hash: Memory allocated for transposition tables (in MB)

Analysis modes

Choose how the engine analyzes positions:
  • Infinite: Analyze until manually stopped
  • Fixed depth: Analyze to a specific depth
  • Time-based: Analyze for a fixed duration
Settings can be synced globally or configured per-tab. Enable Sync globally to apply settings across all tabs.

UCI engine protocol

En Croissant uses the Universal Chess Interface (UCI) protocol to communicate with chess engines. This industry-standard protocol allows:
  • Engine compatibility: Works with any UCI-compatible engine (Stockfish, Komodo, Leela Chess Zero, etc.)
  • Standardized communication: Consistent interface across different engines
  • Advanced configuration: Access engine-specific options through UCI parameters

Adding engines

Navigate to the engines page to:
  1. Add local UCI engines from your system
  2. Configure remote engines via API
  3. Set default parameters for each engine
  4. Test engine compatibility

Tablebase support

For endgame positions with 7 pieces or fewer, En Croissant queries online tablebases to show perfect play:
  • Automatic detection: Tablebase info appears automatically for qualifying positions
  • Outcome display: Shows whether the position is winning, losing, or drawn
  • DTZ/DTM information: Distance to zeroing move or mate for each candidate move
  • Move recommendations: All moves sorted by outcome (wins first, then draws, then losses)
Tablebase information is fetched from online sources and appears in the analysis panel when applicable.

Report generation

The Report tab analyzes entire games to identify:
  • Mistakes, blunders, and inaccuracies
  • Missed opportunities
  • Critical positions
  • Overall game quality

Engine logs

The Logs tab displays raw UCI communication between En Croissant and engines:
  • Commands sent to engines
  • Responses received
  • Useful for debugging engine issues
Engine logs are available when at least one engine is loaded.

Performance tips

  • Limit concurrent engines: Running too many engines may slow analysis
  • Adjust hash size: Larger hash tables improve analysis quality but use more RAM
  • Use appropriate depth: Infinite analysis continues improving evaluations over time
  • Disable when not needed: Pause engines when navigating through games to save resources

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