babel-plugin-check-es2015-constants is a Babel plugin that enforces ES2015's const and let immutability rules at compile time. It prevents accidental re-assignment of const variables, ensuring strict adherence to ES2015 specifications. This helps catch potential bugs early in development, leading to more robust and predictable JavaScript code. Adding this plugin to your Babel configuration helps guarantee that developers properly respect constant declarations.
The npm package babel-plugin-check-es2015-constants saw its peak release activity in November 2015 with 13 versions. Releases gradually declined until May 2016, with sporadic releases in Feb, Mar and May 2016, and Jan 2017. Since then, there have been no further releases up to September 2025.
Babel-plugin-check-es2015-constants downloads show fluctuation. From March 2024 to August 2025 downloads remained around 6 million, peaking in November 2024 at 10.4 million, and then again in July 2025 at 10.7 million. September 2025 downloads are incomplete and significantly lower.
