# Develop KCL 1.x consumers
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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Amazon Kinesis Client Library (KCL) versions 1.x and 2.x are outdated.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).

You can develop a consumer application for Amazon Kinesis Data Streams using the Kinesis Client Library (KCL). 

For more information about KCL, see [About KCL (previous versions)](shared-throughput-kcl-consumers.md#shared-throughput-kcl-consumers-overview).

Choose from the following topics depending on the option you want to use.

**Topics**
+ [Develop a Kinesis Client Library consumer in Java](kinesis-record-processor-implementation-app-java.md)
+ [Develop a Kinesis Client Library consumer in Node.js](kinesis-record-processor-implementation-app-nodejs.md)
+ [Develop a Kinesis Client Library consumer in .NET](kinesis-record-processor-implementation-app-dotnet.md)
+ [Develop a Kinesis Client Library consumer in Python](kinesis-record-processor-implementation-app-py.md)
+ [Develop a Kinesis Client Library consumer in Ruby](kinesis-record-processor-implementation-app-ruby.md)