ChessEditorJS is a simple minimal JavaScript application to edit and view chess games in the Portable Game Notation (PGN) format. This project is coded in Scheme and then transpiled to Javascript. Additionally the editor will analyze a board position and suggest a move using the quite slow but capable Schematic chess engine. Core chess move and Schematic chess engine source code can be viewed here.
To make a move make two clicks of the mouse in the chess board display. Click once for a square containing a source piece followed by a click to a destination square. Illegal moves are blocked. Each move is logged in the text area window.
The plys button is used when analysis is in progress. The number of plys is the number of half moves used by Schematic during analysis. The lower the plys the faster the analysis and weaker the strength of play.
The custom button provides a way to enter a user specified board position that will be applied to the last of the examples.