This is a basic example of using node-canvas version 2.0.0-alpha that exhibits a memory leak. It is an express server that returns a 1200*600-px png image for every request at localhost:3000. Before responding with an image, it also logs the memory usage of the node process.

Run the server with npm start.

Try sending multiple requests to the server, e.g. with the following line of Bash:

for ((x = 0; x <= 1000; x++ )); do time curl -s -I -XGET http://localhost:3000/; done

and observe how the rss portion of memory usage is steadily increasing.

For comparison, try the same multiple requests against the server that uses the 1.x branch of node canvas. There, the rss portion of memory remains stable.