Overview

Deno-native parser library for K9 (Self-Validating Components), written in ReScript.

K9 is a specification format for self-validating software components with built-in pedigree metadata, security levels (Kennel/Yard/Hunt), target platform constraints, lifecycle recipes, and deployment contracts. This library provides a complete parser and renderer for .k9 specification files, compiled from ReScript to JavaScript ES modules for use with Deno.

Features

• Parse K9 component specifications from strings or files

• Render AST back to .k9 YAML-like format (round-trip support)

• Security level hierarchy: Kennel (pure data), Yard (controlled), Hunt (full execution)

• Pedigree metadata with provenance tracking

• Target platform constraints (OS, edge, Podman, memory)

• Lifecycle recipes (install, validate, deploy, migrate, custom)

• Self-validation blocks (checksum, pedigree version)

• Format detection (YAML-like .k9 vs Nickel .k9.ncl)

• Zero dependencies beyond ReScript standard library

Quick Start

# Build ReScript to JS
deno task build

# Use in your Deno project
deno add jsr:@hyperpolymath/k9

import { parse, render, parseErrorToString } from "@hyperpolymath/k9";

const result = parse(`K9!
---
metadata:
  name: hello-k9
  version: 0.1.0
  description: A simple K9 component
security:
  trust_level: 'Kennel
  allow_network: false
  allow_filesystem_write: false
  allow_subprocess: false
`);
// result is Ok(component) or Error(parseError)

Module Structure

Module	Purpose
K9.res	Main module — re-exports all public API
K9_Types.res	Core data types: component, pedigree, securityLevel, target, recipes, validation, contract
K9_Parser.res	Line-oriented parser: .k9 text to typed AST
K9_Renderer.res	Renderer: typed AST back to .k9 text

K9 Format Reference

K9!
---
metadata:
  name: my-component
  version: 1.0.0
  description: A self-validating component
  author: Jonathan D.A. Jewell
  license: MPL-2.0

security:
  trust_level: 'Yard
  allow_network: true
  allow_filesystem_write: false
  allow_subprocess: false

target:
  os: Linux
  is_edge: false
  requires_podman: true
  memory: 512M

recipes:
  install: deno install
  validate: deno task test
  deploy: deno task deploy

validation:
  checksum: sha256:abc123...
  pedigree_version: 1.0
  hunt_authorized: false

tags:
  - deno
  - rescript
  - parser

Security Levels

Level	Permissions	Use Case
’Kennel	No execution, no network, no filesystem, no subprocess	Pure data, configuration, static assets
’Yard	Controlled execution, network allowed	Services, APIs, constrained tools
’Hunt	Full execution, all permissions	Build tools, deployment scripts, system administration

Development

deno task build    # Compile ReScript
deno task clean    # Clean build artifacts
deno task test     # Run tests

Related Libraries

• k9-rs — Rust implementation

• k9-haskell — Haskell implementation

• k9_gleam — Gleam implementation

• tree-sitter-k9 — Tree-sitter grammar

• vscode-k9 — VS Code extension

License

SPDX-License-Identifier: CC-BY-SA-4.0

Copyright (c) 2026 Jonathan D.A. Jewell (hyperpolymath)

See LICENSE for details.