SpeechMarkdown Rust

High-performance SpeechMarkdown parser written in Rust. Converts SpeechMarkdown syntax to platform-specific SSML for Amazon Alexa, Google Assistant, Microsoft Azure, and more.

Install

Language	Package	Install
Rust	speechmarkdown-rust	cargo add speechmarkdown-rust
Python	speechmarkdown-rust	pip install speechmarkdown-rust
Node.js	speechmarkdown	npm install speechmarkdown
.NET	SpeechMarkdown	dotnet add package SpeechMarkdown
Swift	Release asset	See Swift section below

Supported Platforms

Platform	String ID
Amazon Alexa	"amazon-alexa" or "alexa"
Google Assistant	"google-assistant" or "google"
Microsoft Azure	"microsoft-azure" or "azure"
Apple	"apple"
W3C	"w3c"
Samsung Bixby	"samsung-bixby" or "bixby"
ElevenLabs	"elevenlabs"
IBM Watson	"ibm-watson" or "watson"

API

All bindings expose the same core methods:

Method	Returns	Description
to_ssml(input, platform)	string	Convert SpeechMarkdown to SSML for the given platform
to_text(input)	string	Convert SpeechMarkdown to plain text (strips all markup)
to_smd(ssml)	string	Convert SSML to SpeechMarkdown (best-effort, lossy for unsupported elements)
parse(input)	string (JSON)	Parse SpeechMarkdown and return the AST as JSON
is_speech_markdown(input)	bool	Check if a string contains SpeechMarkdown syntax
validate(input)	bool	Validate that SpeechMarkdown parses without errors
supported_ssml(platform)	string (JSON)	Get supported SSML elements for a platform

Usage

Rust

use speechmarkdown_rust::{SpeechMarkdownParser, Platform};

// Convert to SSML
let ssml = SpeechMarkdownParser::to_ssml(
    "Hello (world)[emphasis:\"strong\"]",
    Platform::AmazonAlexa,
)?;

// Convert to plain text
let text = SpeechMarkdownParser::to_text("Hello (world)[emphasis:\"strong\"]")?;

// Parse to AST (JSON string)
let ast = SpeechMarkdownParser::parse("Hello world")?;

// Check if input contains SpeechMarkdown syntax
if SpeechMarkdownParser::is_speech_markdown(&input) {
    // ...
}

// Validate input
SpeechMarkdownParser::validate(&input)?;

// Convert SSML back to SpeechMarkdown (best-effort)
let smd = SpeechMarkdownParser::to_smd(r#"<speak><emphasis level="strong">word</emphasis></speak>"#)?;
// Returns: ++word++

Python

from speechmarkdown_rust import to_ssml, to_text, parse, is_speech_markdown, validate

ssml = to_ssml('Hello (world)[emphasis:"strong"]', 'amazon-alexa')
text = to_text('Hello (world)[emphasis:"strong"]')
ast = parse('Hello world')

is_smd = is_speech_markdown('Hello (world)[emphasis:"strong"]')  # True
is_smd = is_speech_markdown('Hello world')                       # False

validate('Hello (world)[emphasis:"strong"]')  # raises ValueError if invalid

# Convert SSML to SpeechMarkdown (best-effort)
smd = to_smd('<speak><emphasis level="strong">word</emphasis></speak>')
# Returns: ++word++

Node.js

const { to_ssml, to_text, parse, is_speech_markdown, validate } = require('speechmarkdown')

const ssml = to_ssml('Hello (world)[emphasis:"strong"]', 'amazon-alexa')
const text = to_text('Hello (world)[emphasis:"strong"]')
const ast = parse('Hello world')

is_speech_markdown('Hello (world)[emphasis:"strong"]')  // true
is_speech_markdown('Hello world')                       // false

validate('Hello (world)[emphasis:"strong"]')  // throws if invalid

// Convert SSML to SpeechMarkdown (best-effort)
const smd = to_smd('<speak><emphasis level="strong">word</emphasis></speak>')
// Returns: ++word++

.NET (C#)

using SpeechMarkdown;

var parser = new SpeechMarkdownParser();

string ssml = parser.ToSsml("Hello (world)[emphasis:\"strong\"]", Platform.AmazonAlexa);
string text = parser.ToText("Hello (world)[emphasis:\"strong\"]");
string json = parser.ParseToJson("Hello world");

bool isSmd = parser.IsSpeechMarkdown("Hello (world)[emphasis:\"strong\"]"); // true
parser.Validate("Hello (world)[emphasis:\"strong\"]"); // throws on invalid

// Convert SSML to SpeechMarkdown (best-effort)
string smd = parser.ToSmd("<speak><emphasis level=\"strong\">word</emphasis></speak>");
// Returns: ++word++

Swift

The repo root contains a Package.swift with a binary target pointing to a pre-built XCFramework. This enables both local development and Swift Package Index integration.

Option 1 — SPM (recommended):

// In your Package.swift:
.package(url: "https://github.com/AACTools/speechmarkdown-rust", branch: "spm")

Option 2 — Local package: Download speechmarkdown-swift-package.zip from the latest release, unzip, and add as a local package in Xcode (File > Add Packages > Add Local).

Includes macOS (arm64 + x86_64), iOS device (arm64), and iOS simulator (arm64) slices.

To build from source: ./build-swift-package.sh

import SpeechMarkdown

let parser = SpeechMarkdownParser()

let ssml = try parser.toSsml(input: "Hello (world)[emphasis:\"strong\"]", platform: "amazon-alexa")
let text = try parser.toText(input: "Hello (world)[emphasis:\"strong\"]")
let json = try parser.parseToJson(input: "Hello world")

let isSmd = parser.isSpeechMarkdown(input: "Hello (world)[emphasis:\"strong\"]") // true
try parser.validate(input: "Hello (world)[emphasis:\"strong\"]") // throws on invalid

// Convert SSML to SpeechMarkdown (best-effort)
let smd = try parser.toSmd(ssml: "<speak><emphasis level=\"strong\">word</emphasis></speak>")
// Returns: ++word++

C API

#include "speechmarkdown.h"

// Convert to SSML
const char* ssml = speechmarkdown_to_ssml("Hello (world)[emphasis:\"strong\"]", "amazon-alexa");
speechmarkdown_free((char*)ssml);

// Convert to plain text
const char* text = speechmarkdown_to_text("Hello (world)[emphasis:\"strong\"]");
speechmarkdown_free((char*)text);

// Parse to JSON
const char* json = speechmarkdown_parse("Hello world");
speechmarkdown_free((char*)json);

// Check for SpeechMarkdown syntax
bool is_smd = speechmarkdown_is_speech_markdown("Hello (world)[emphasis:\"strong\"]");

// Validate
bool valid = speechmarkdown_validate("Hello (world)[emphasis:\"strong\"]");

// Convert SSML to SpeechMarkdown (best-effort)
const char* smd = speechmarkdown_to_smd("<speak><emphasis level=\"strong\">word</emphasis></speak>");
speechmarkdown_free((char*)smd);

// Get last error (thread-local)
const char* err = speechmarkdown_get_error();

Building from Source

cargo build --release

This produces:

• Windows: target/release/speechmarkdown_rust.dll
• macOS: target/release/libspeechmarkdown_rust.dylib
• Linux: target/release/libspeechmarkdown_rust.so

License

MIT