Java lacks a native zip() method for streams, requiring third-party libraries like Google Guava. Java 22 introduces stream gatherers (JEP 461) as a preview API, enabling custom intermediary stream operations. A custom zipping gatherer implementation is demonstrated that connects two streams element-by-element, applying a user-provided function to each pair. The implementation stops when either stream is exhausted, with notes on how left-join semantics could be added. A limitation is that this gatherer cannot be parallelized due to the inability to access the second stream's spliterator during parallel subdivision. An ObjToIntZipper variant is also provided to avoid int boxing overhead.
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