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@kcl-lang

The KCL Programming Language

KCL is an open-source constraint-based record & functional language mainly used in configuration and policy scenarios.

Hey, this is KCL community 👋

💻 Website | 👩‍💻 Quick Start | 👀 Blog | 📦 Modules | 🔧 SDKs | 🔌 Plugins | 💻 IDE Extensions | 🎮 Playground |☸️ KRM KCL Spec

KCL is a constraint-based record & functional language mainly used in cloud-native configuration and policy scenarios. It is hosted by the Cloud Native Computing Foundation (CNCF) as a Sandbox Project.

What is it for?

KCL aims to provide the following capabilities:

  • Hide infrastructure and platform details by defining more appropriate API abstractions to reduce the burden of developers.
  • Mutate and validate existing config files or manifests through numerous community modules.
  • Manage large-scale configuration data across teams without side effects through configuration and policy language for GitOps.

Specifically, KCL can

  • Improve the ability to semantically validate configurations at the code level, such as schema definitions, required/optional attribute requirements, types, range constraints, and etc.
  • Provide capabilities for writing, combining, and abstracting configuration chunks, such as structure definitions, structure inheritance, constraint definitions, and configuration policy merging.
  • Enhance configuration flexibility by adopting modern programming language features, such as conditional statements, loops, functions, and package management, to improve configuration reusability.
  • Provide comprehensive toolchain support, including rich IDE extensions and toolchains support to reduce the learning curve and enhance the user experience.
  • Enable easier sharing, propagation, and delivery of configurations between different teams/roles through package management tools and OCI registries.
  • Offer a high-performance compiler to meet the demands of scalable configuration scenarios, such as rendering performance for generating configurations for different environments and topologies based on a baseline configuration and configuration automation modification performance requirements.
  • Improve automation integration capabilities through multi-language SDKs, KCL language plugins, and other means, significantly reducing the learning curve while leveraging the value of configuration and policy writing with KCL.
  • Used as a platform engineering language to deliver modern apps with KusionStack.

Documents

See the KCL website for more information.

Community

See the community for ways to join us.

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  1. kcl kcl Public

    KCL Programming Language Core and API (CNCF Sandbox Project). https://kcl-lang.io

    Rust 2.2k 155

  2. modules modules Public

    KCL Community Modules. View on Artifact Hub: https://artifacthub.io/packages/search?org=kcl&sort=relevance&page=1

    Roff 35 46

  3. lib lib Public

    KCL Multiple Language Bindings including Rust, Go, Python, Java, Kotlin, .NET, Swift, Lua, Node.js, Zig, C, C++, WASM, etc.

    C# 16 13

  4. krm-kcl krm-kcl Public

    Kubernetes Resource Model KCL Specification and Integrations including Kubectl, Kustomize, Helm, Helmfile, Crossplane, KPT, etc.

    Go 29 17

  5. cli cli Public

    KCL Programming Language Command Line Interface (CLI).

    Go 31 20

  6. kcl-lang.io kcl-lang.io Public

    KCL Website and Documentation Repo

    TypeScript 20 49

Repositories

Showing 10 of 44 repositories
  • krm-kcl Public

    Kubernetes Resource Model KCL Specification and Integrations including Kubectl, Kustomize, Helm, Helmfile, Crossplane, KPT, etc.

    kcl-lang/krm-kcl’s past year of commit activity
    Go 29 Apache-2.0 17 0 1 Updated Nov 30, 2025
  • scoop-bucket Public

    KCL windows scoop bucket

    kcl-lang/scoop-bucket’s past year of commit activity
    2 Apache-2.0 1 0 0 Updated Nov 30, 2025
  • homebrew-tap Public

    The Homebrew tap for the KCL programming language projects.

    kcl-lang/homebrew-tap’s past year of commit activity
    Ruby 3 Apache-2.0 3 2 1 Updated Nov 30, 2025
  • cli Public

    KCL Programming Language Command Line Interface (CLI).

    kcl-lang/cli’s past year of commit activity
    Go 31 Apache-2.0 20 10 1 Updated Nov 30, 2025
  • kpm Public

    KCL Package Manager

    kcl-lang/kpm’s past year of commit activity
    Go 36 Apache-2.0 61 15 (6 issues need help) 10 Updated Nov 30, 2025
  • kcl-go Public

    KCL Go SDK

    kcl-lang/kcl-go’s past year of commit activity
    Go 55 Apache-2.0 31 7 (3 issues need help) 0 Updated Nov 30, 2025
  • lib Public

    KCL Multiple Language Bindings including Rust, Go, Python, Java, Kotlin, .NET, Swift, Lua, Node.js, Zig, C, C++, WASM, etc.

    kcl-lang/lib’s past year of commit activity
    C# 16 Apache-2.0 13 4 0 Updated Nov 30, 2025
  • kcl Public

    KCL Programming Language Core and API (CNCF Sandbox Project). https://kcl-lang.io

    kcl-lang/kcl’s past year of commit activity
    Rust 2,212 Apache-2.0 155 125 (16 issues need help) 2 Updated Nov 30, 2025
  • helm-kcl Public

    Helm KCL Plugin

    kcl-lang/helm-kcl’s past year of commit activity
    Go 17 Apache-2.0 4 2 2 Updated Nov 25, 2025
  • kcl-openapi Public

    KCL OpenAPI Integration

    kcl-lang/kcl-openapi’s past year of commit activity
    Go 8 Apache-2.0 8 6 (2 issues need help) 6 Updated Nov 25, 2025

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