Nyl

Nyl is a fast Kubernetes manifest generator built in Rust, with Helm-based components, remote manifest support, cluster-aware rendering, and Kubernetes GitOps output.

Everything Nyl does is declared in Git, and every command takes the same path over those declarations: a render on a laptop while bootstrapping a cluster is the render CI publishes for Argo CD.

Python 3.11+ users can install nyl from PyPI to render and inspect manifests through a separately installed Nyl CLI. See the Python client for installation, resource selectors, container helpers, and rendered-manifest tests.

Highlights

• Component-oriented workflow (Helm chart-backed resources)
• RemoteManifest resources for HTTPS-hosted YAML/JSON
• Jinja2-compatible templating (MiniJinja)
• Kubernetes-shaped Cluster and DeploymentTarget configuration
• render, diff, and apply commands
• Rendered manifest GitOps workflow for ArgoCD, Flux, or plain kubectl
• CI image with Nyl, Helm, Git, Git LFS, SOPS, and Kyverno CLI

Quick Start

Install with mise:

[tools."github:NiklasRosenstein/nyl"]
version = "0.4.1"
version_prefix = "v"

mise install
nyl init platform --minimal
cd platform
git init
nyl create repository deploy --repo-url https://example.invalid/deploy.git
nyl create cluster dev --context kind-kind
nyl capture cluster dev
nyl create target dev
nyl render --target dev apps.yaml

Feature Examples

Component

apiVersion: components.k8s.nyl/v1
kind: example/v1/Nginx
metadata:
  name: my-nginx
  namespace: default
spec:
  replicas: 3
  image: nginx:1.25

Render:

nyl render examples/components/manifests/nginx.yaml --kube-version 1.30.0 --kube-api-versions v1

RemoteManifest

apiVersion: k8s.nyl/v1
kind: RemoteManifest
metadata:
  name: shared-crds
spec:
  url: https://example.com/platform/crds.yaml

CI image

The published image is a shell-friendly rendering environment with no fixed entrypoint:

render:
  image: ghcr.io/niklasrosenstein/nyl:TAG
  script:
    - nyl render-tree --target production --output-dir deploy

Repository Layout

• nyl/: main Rust crate and CLI
• docker/: CI rendering image
• examples/: runnable examples

Docs

• Full docs: https://niklasrosenstein.github.io/nyl/
• CLI and development details: nyl/README.md
• Components guide: nyl/book/src/content/docs/rendering/components/overview.md

License

MIT (see LICENSE).