(ruby): Ruby language bindings for AWS CDK

[omarqureshi]

Describe the feature

Add Ruby as a first-class supported language for AWS CDK, alongside TypeScript, Python, Java, C#/.NET and Go. This would let Ruby-centric teams author CDK infrastructure in Ruby (e.g. AWSCDK::S3::Bucket) via a published aws-cdk-lib Ruby gem, instead of context-switching to another language.

This issue tracks the aws-cdk-lib side of the work. The enabling changes live in jsii (compiler, the jsii-pacmak Ruby target, and the @jsii/ruby-runtime gem); aws-cdk-lib only needs additive per-module .jsiirc.json Ruby target configuration.

Use Case

Ruby remains a primary language for many infrastructure and platform teams, who today either maintain a parallel toolchain in another language or avoid CDK entirely. Demand has been long-standing and well-documented — the original request has been open since 2018 and is one of the most-reacted language asks.

Native Ruby bindings remove that friction: infrastructure is defined in the language the team already uses, with idiomatic Ruby ergonomics (snake_case methods, keyword-argument structs, PascalCase modules).

Proposed Solution

Design is captured in RFC 0935: Ruby language bindings — tracking issue aws/aws-cdk-rfcs#935 (full RFC text).

The change is strictly additive — no breaking changes to existing languages, and only an additive targets.ruby schema extension.

Implementation is split across repositories:

• jsii (compiler + jsii-pacmak Ruby target + @jsii/ruby-runtime): feat(ruby): Ruby language bindings jsii#5178 (draft).
• aws-cdk-lib: per-module .jsiirc.json Ruby target configuration (gem/module naming + acronyms) across the library. A self-contained branch is ready (omarqureshi/aws-cdk@ruby-language-bindings, a single commit with no dev scaffolding); a PR will follow this issue.

Naming follows the RFC: root namespace AWSCDK, idiomatic Ruby member/module casing, and AWS-prefix de-duplication (aws-s3 → AWSCDK::S3::Bucket). Minimum Ruby is 3.3 (MRI).

Dependency: this is gated on a jsii-compiler release with Ruby target support (tracked in the jsii PR above). Until that ships, the aws-cdk-lib PR's CI will be red by design. End-to-end generation and gem publishing have already been validated against a pre-release build of the compiler.

Other Information

• Rosetta (code-example translation) for Ruby is out of scope for the initial submission and will follow separately.
• JRuby/TruffleRuby are out of scope for the initial release (MRI only).

Acknowledgements

• I may be able to implement this feature request
• This feature might incur a breaking change

AWS CDK Library version (aws-cdk-lib)

n/a — cross-cutting language-binding addition to aws-cdk-lib (targets current main); not tied to a released version.

AWS CDK CLI version

n/a — code-generation / library feature, not CLI-specific.

Environment details (OS name and version, etc.)

n/a — affects jsii code generation and packaging, not a runtime environment.

[pahud]

Hi @omarqureshi,

Thanks for driving this — the RFC, jsii PR, and aws-cdk-lib branch are all clearly scoped. This is a long-standing community ask and good to see it progressing.

Since this is gated on jsii#5178 (Ruby target in the compiler), we'll keep this open as the aws-cdk-lib tracking issue. Once the jsii side ships, the PR adding per-module .jsiirc.json Ruby config can land here.

Labeling feature-request.

[omarqureshi]

Happy to help @pahud - the one thing I'm missing is someone from AWS to act as a bar raiser, could someone be assigned to this? I'm in #cdk.dev on Slack but unable to get someone, would really appreciate the assist here.

Additionally I have publicly published pre-release gems to my own gemserver (https://rubygems.omarqureshi.net) and have a short (noisy) video where I go through the deployment of an S3 bucket at https://www.youtube.com/watch?v=Tu2CkWKc954