Version Details and Security Vulnerabilities

Version 4.17.20 of the @types/lodash package offers updated TypeScript definitions for the popular Lodash utility library. This release, published on July 1st, 2025, succeeds version 4.17.19, which was released on June 25th, 2025. While both versions maintain the same MIT license and source code repository on DefinitelyTyped, a key difference lies in the unpacked size of the package. Version 4.17.20 exhibits a slightly larger unpacked size of 869,050 bytes compared to 868,065 bytes in the previous version, suggesting minor improvements and enhancements to the type definitions which results in a larger, albeit negligibly, final package size.

For developers using Lodash with TypeScript, upgrading to version 4.17.20 provides potentially enhanced type safety and more accurate code completion. Developers should note the small increase in the final deployed package size, and upgrade their deployments with this in mind, taking into consideration any deployment size limits they might have. These updated definitions ensure better integration between Lodash and TypeScript projects, leading to improved code maintainability and fewer runtime errors. As both versions share identical dependencies and peer dependencies (none declared), the upgrade process should be straightforward and should not trigger any new version conflicts, assuming your project targets lodash itself and not its type definitions. This release continues to supply 707 files within the package.