# Develop custom consumers with shared throughput using KCL
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**Important**  
Amazon Kinesis Client Library (KCL) versions 1.x and 2.x are outdated. KCL 1.x will reach end-of-support on January 30, 2026. We **strongly recommend** that you migrate your KCL applications using version 1.x to the latest KCL version before January 30, 2026. To find the latest KCL version, see [Amazon Kinesis Client Library page on GitHub](https://github.com/awslabs/amazon-kinesis-client). For information about the latest KCL versions, see [Use Kinesis Client Library](kcl.md). For information about migrating from KCL 1.x to KCL 3.x, see [Migrating from KCL 1.x to KCL 3.x](kcl-migration-1-3.md).

One of the methods of developing a custom consumer application with shared throughput is to use the Kinesis Client Library (KCL). 

Choose from the following topics for the KCL version you are using.

**Topics**
+ [Develop KCL 1.x consumers](developing-consumers-with-kcl.md)
+ [Develop KCL 2.x Consumers](developing-consumers-with-kcl-v2.md)