Markdown Core is a cross-platform Markdown parser with a shared immutable abstract syntax tree (AST) for C, Swift, Kotlin, and ECMAScript. One C engine provides consistent parsing behavior and source locations across all bindings.

The library provides synchronous parsing and read-only AST traversal. It has one Markdown dialect with no parse options. Applications own rendering and keep the source text when they need it; the parser does not retain the input.

Read the Markdown syntax guide to learn the language, or the documentation index for the AST and source-location contracts.

The Swift package supports iOS 26 and macOS 26 or later. Add the MarkdownCore product to your target:

.package(url: "https://github.com/nouprax/markdown-core", from: "3.0.0")

import MarkdownCore

let document = try Document.parse("Hello, Markdown.")
print(document.dump())

The AST is an immutable, Sendable value tree with typed visitors and stack-safe walking. Child relations use read-only MarkupCollection and MarkupGroups values with constant-time random access; use Array(...) when an array is required. Retaining a subtree keeps its immutable Swift store alive. The native C document is freed before parse returns. See Swift storage for ownership and lifecycle details.

Add the dependency to a Kotlin Multiplatform source set:

kotlin {
    sourceSets {
        commonMain.dependencies {
            implementation("com.nouprax:kotlin-markdown-core:3.0.0")
        }
    }
}

import com.nouprax.markdown.core.Document

val document = Document.parse("Hello, Markdown.")
println(document.dump())

Supported targets are Android API 21 or later, JVM 17, macOS arm64, and Linux x64. Native runtime dependencies are included. On JDK 26 or later, launch JVM applications with --enable-native-access=ALL-UNNAMED to avoid the native-access warning from the JNI loader.

pnpm add @nouprax/es-markdown-core

import { Document, MarkupDumper } from "@nouprax/es-markdown-core";

const document = Document.parse("Hello, Markdown.");
console.log(MarkupDumper.dump(document));

The ESM package supports Node.js 20 or later and browsers that can load its WebAssembly asset. Parsing is synchronous once the import resolves. TypeScript values are recursively readonly; JavaScript objects are not runtime-frozen.

Link the installed CMake target:

find_package(markdown-core CONFIG REQUIRED)
target_link_libraries(my-app PRIVATE markdown-core::markdown-core)

Include <markdown_core.h> and call markdown_core_document_parse. Release successful parses with markdown_core_document_free; node and string views borrow from that document. Release errors and allocated dumps with markdown_core_error_free and markdown_core_dump_free.

Independent parses may run concurrently. Read-only access to a document is safe while it remains alive. See the public C header for the complete API and ownership rules.

Start with the toolchain and environment guide, validate your setup with scripts/init-environment.sh --check, then install dependencies:

pnpm install --frozen-lockfile

Build the package you are working on:

pnpm build:c
pnpm build:swift
scripts/gradle.sh :packages:kotlin-markdown-core:jvmJar
pnpm --dir packages/es-markdown-core build

The C CLI at build/cmake/packages/markdown-core/core/markdown-core reads files or standard input and prints a debug AST dump. To install the C library:

cmake --install build/cmake --prefix /path/to/prefix

Run the tests for your host, such as pnpm test:c-host and pnpm conformance:c-host. See testing for all platform targets, sanitizers, conformance checks, and benchmarks. pnpm verify runs the repository's formatting, lint, contract, and audit checks.

The four bindings live in packages/; shared executable fixtures live in specs/. Reader documentation lives in docs/specs/, implementation design in docs/architecture/, and consumer examples in samples/.

For releases, follow the release guide and change log.

Markdown Core is an independent project derived from cmark, cmark-gfm, and DongyuZhao/cmark-gfm. It preserves the applicable upstream copyright and license notices. See LICENSE, COPYING, and UPSTREAM.md for licensing and lineage.