CODESYS has launched the first version of CODESYS 4, the next generation of its engineering environment for industrial automation. The innovation lies in the development tool itself rather than in the underlying technology: CODESYS 4 relies on the same field-proven compiler, libraries and runtime system as CODESYS 3. In practice, this means existing controllers will keep running exactly the same code they run today.
Key Features of CODESYS 4
The new platform offers a modern technical foundation that can be used alongside the established CODESYS Development System. Highlights include:
- Engineering in a web browser, with no dependency on Microsoft Windows as the operating system.
- A text-based file format and a complete command-line interface (CLI), allowing seamless integration into CI/CD pipelines without manual steps.
- Solid core functionality: Structured Text (ST) and Ladder Diagram (LD) editors with syntax highlighting, auto-completion and inline monitoring, plus a Modbus TCP configurator.
- Compatibility with CODESYS 3 libraries and runtime system.
What CODESYS 4 Does Not Yet Offer
The company is clear that this first release is not a full development system designed to replace CODESYS 3. Functions and products already available in the current version, such as visualization, fieldbus configurators, motion control and many everyday convenience features, are not yet part of CODESYS 4.
Who Should Try It Now?
CODESYS 4 is particularly attractive in three scenarios:
- Library development in Structured Text: changes can be compared and merged in Git, and compiled libraries can be built from the command line without a GUI, with compatibility for both CODESYS 3 and CODESYS 4.
- Small device projects using Modbus TCP: write the logic in ST and LD, map the I/Os in the Modbus configurator, download the project and monitor variables directly in the editor.
- Engineers who want to see where industrial control programming is heading, without having to migrate their existing projects.
An Architecture Built to Grow
CODESYS explains that it deliberately prioritized architecture over the feature list: building on this foundation, the tool’s capabilities will expand with every new release. For projects that need more functionality, CODESYS 3 remains the recommended choice. Both systems will continue to be developed in parallel, and switching to CODESYS 4 is not required.
Availability and Licensing
CODESYS 4 can be used free of charge until the end of 2028. In addition, users who already develop PLC applications professionally with CODESYS Development System 3 and the tools included in the Professional Developer Edition (such as CODESYS Git or the CODESYS MCP Server) will receive CODESYS 4 as an additional tool in their license bundle at no extra cost.