Extend Shallow

extend-shallow is a minimalist JavaScript utility designed to merge the enumerable properties of one or more source objects into a target object. It performs a *shallow* merge, meaning only top-level properties are copied; nested objects or arrays are copied by reference rather than being cloned. The current stable version is 3.0.2, last published in 2017, indicating a mature and stable, but not actively feature-developed, codebase. It primarily targets Node.js environments from version 0.10.0 upwards, supporting CommonJS module syntax. While modern JavaScript environments widely support `Object.assign()` for similar functionality, extend-shallow serves as a lightweight alternative, particularly useful in legacy environments or when a direct, unopinionated shallow merge is explicitly required without the overhead of polyfills or broader compatibility layers. Its key differentiator lies in its focused, single-purpose design, making it a very small footprint utility.