YAMLScript¶

Next-generation YAML programming language for advanced configuration management.

Overview¶

YAMLScript is an innovative programming language that extends YAML with computation capabilities. It looks like YAML but can execute code, making it perfect for advanced configuration management.

Website: yamlscript.org
Repository: github.com/yaml/yamlscript
Status: Active development
Creator: Ingy dot Net (YAML co-creator)

What is YAMLScript?¶

YAML + Programming¶

YAMLScript is:

Valid YAML - Any YAMLScript is valid YAML
Executable - Can evaluate expressions and run functions
Familiar - Uses YAML syntax you already know
Powerful - Supports variables, functions, and logic

The Problem YAMLScript Solves¶

Traditional YAML is static data. YAMLScript adds computation:

Traditional YAML (static):

database:
  host: localhost
  port: 5432
  url: "postgres://localhost:5432/mydb"  # Redundant!

YAMLScript (computed):

database:
  host: localhost
  port: 5432
  url: =>"postgres://$host:$port/mydb"  # Computed!

Key Features¶

Computation in YAML¶

Embed expressions directly in YAML:

server:
  host: api.example.com
  port: 443
  url: =>"https://$host:$port"  # Computed at runtime

Functions and Logic¶

Define reusable functions:

!yamlscript/v0

defn greeting(name):
  "Hello, $name!"

message: =>greeting("World")  # "Hello, World!"

Dynamic Configuration¶

Generate configuration programmatically:

servers:
  - for: i in(range(1, 4))
    name: "server-$i"
    port: =>(+ 8000 i)

Results in:

servers:
  - name: server-1
    port: 8001
  - name: server-2
    port: 8002
  - name: server-3
    port: 8003

Use Cases¶

Infrastructure as Code¶

Generate complex configurations:

!yamlscript/v0

regions: [us-east-1, us-west-2, eu-west-1]

resources:
  - for: region in regions
    type: ec2-instance
    region: =>region
    tags:
      Name: "app-$region"

Environment-Specific Config¶

One file, multiple environments:

!yamlscript/v0

env: =>ENV.APP_ENV or "development"

database:
  host: =>
    when(env == "production"):
      "prod-db.example.com"
    else:
      "localhost"

Advanced GitOps¶

Smart Kubernetes manifests:

!yamlscript/v0

replicas: =>
  if(ENV.LOAD == "high"): 10
  else: 3

deployment:
  replicas: =>replicas
  resources:
    cpu: =>"${replicas * 100}m"

Enterprise Features¶

YES Leader Benefits¶

YES Leader tier members get access to:

YAMLScript enterprise license
Priority support for YAMLScript implementation
Custom function libraries for enterprise use cases
Training and consulting on YAMLScript adoption
Early access to new features

Security & Compliance¶

Sandboxed execution environment
Audit logging for all computations
Policy enforcement capabilities
No arbitrary code execution

Integration¶

YAMLScript integrates with:

CI/CD pipelines
Kubernetes operators
Configuration management tools
GitOps workflows

Getting Started¶

Installation¶

# Install YAMLScript CLI
curl https://yamlscript.org/install.sh | bash

# Or via package managers
brew install yamlscript  # macOS
apt install yamlscript   # Debian/Ubuntu

Your First YAMLScript¶

Create config.ys:

!yamlscript/v0

name: "YAMLScript Example"
version: "1.0.0"
timestamp: =>now()
greeting: =>"Hello from YAMLScript at $timestamp"

Run it:

ys config.ys

Learn More¶

Development Status¶

YAMLScript is under active development:

Current: v0.1 - Core language features
Q1 2026: v0.5 - Enterprise features, security hardening
Q2 2026: v1.0 - Production-ready release

Roadmap¶

Support YAMLScript¶

YAMLScript development is funded through the YES Program:

YES Members: Beta access to YAMLScript
YES Partners: Early access and training
YES Leaders: Enterprise license and custom development

Join YES to Support YAMLScript →

Resources¶

Enterprise Beta

YES members can request early access to YAMLScript enterprise features. Contact us for more information.