Spark is a command-line tool that generates sparklines — small inline text charts — directly in your shell. The project is hosted at git.zx2c4.com/spark and was discussed on Hacker News, where it gathered 13 points and 1 comment.

Sparklines let users visualize numeric data without launching a separate graphing tool. The utility accepts input from standard streams, making it easy to pipe output from other shell commands into Spark for quick visual summaries of trends, history, or measurements.

The project is authored by Jason Donenfeld, known in the community as zx2c4, the creator of WireGuard. The tool is open source and available via the linked Git repository.

Readers interested in shell productivity utilities and lightweight data visualization can explore Spark through its project page and the Hacker News discussion thread linked above.