crosspost

Cross-post messages to multiple social media platforms from Rust.

A Rust rewrite and expansion of the @humanwhocodes/crosspost JavaScript library. Supports 16 platforms with typed credentials, concurrent posting, and per-platform error isolation.

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Quick Start

Add to your Cargo.toml:

[dependencies]
crosspost = { git = "https://github.com/GraftAI-com/crosspost-rs.git" }
tokio = { version = "1", features = ["full"] }

use crosspost::{Client, BlueskyStrategy, BlueskyCredentials, MastodonStrategy, MastodonCredentials, PostResult};

#[tokio::main]
async fn main() -> crosspost::Result<()> {
    let client = Client::new(vec![
        Box::new(BlueskyStrategy::new(BlueskyCredentials {
            identifier: "user.bsky.social".into(),
            password: "app-password".into(),
            host: None,
        })?),
        Box::new(MastodonStrategy::new(MastodonCredentials {
            access_token: "your-token".into(),
            host: "mastodon.social".into(),
        })?),
    ]);

    let results = client.post("Hello from Rust!", None).await;

    for result in &results {
        match result {
            PostResult::Success { name, url, .. } => {
                println!("Posted to {}: {}", name, url.as_deref().unwrap_or("ok"));
            }
            PostResult::Failure { name, reason } => {
                println!("Failed on {}: {}", name, reason);
            }
        }
    }

    Ok(())
}

Load credentials from environment

Each strategy has a from_env() constructor that reads platform-specific environment variables:

use crosspost::{Client, BlueskyStrategy, TwitterStrategy};

let client = Client::new(vec![
    Box::new(BlueskyStrategy::from_env()?),
    Box::new(TwitterStrategy::from_env()?),
]);

Set CROSSPOST_DOTENV=1 to auto-load a .env file, or CROSSPOST_DOTENV=/path/to/.env for a custom path.

Post to specific platforms

use crosspost::PostToEntry;

let results = client.post_to(&[
    PostToEntry {
        strategy_id: "bluesky".into(),
        message: "Short post for Bluesky".into(),
        images: None,
    },
    PostToEntry {
        strategy_id: "mastodon".into(),
        message: "Longer post with more detail for Mastodon...".into(),
        images: None,
    },
]).await;

---

Supported Platforms (16)

Platform	Strategy	Auth	Images	Max Length
Twitter/X	TwitterStrategy	OAuth2 bearer	Yes (upload)	280 (URLs=23)
Bluesky	BlueskyStrategy	App password	Yes (blob)	300 (URLs=27)
Mastodon	MastodonStrategy	OAuth2 bearer	Yes (media)	500
LinkedIn	LinkedInStrategy	OAuth2 bearer	Yes (3-step)	3,000
Facebook	FacebookStrategy	OAuth2 bearer	Yes (multi)	63,206
Instagram	InstagramStrategy	OAuth2 bearer	Yes	2,200
Discord Bot	DiscordStrategy	Bot token	Yes (multipart)	2,000
Discord Webhook	DiscordWebhookStrategy	Webhook URL	Yes (multipart)	2,000
Telegram	TelegramStrategy	Bot API	Yes (sendPhoto)	4,096
Slack	SlackStrategy	Bot token	Yes (3-step)	40,000
Dev.to	DevtoStrategy	API key	Yes (base64 md)	Unlimited
Nostr	NostrStrategy	Private key	No	280
YouTube	YouTubeStrategy	OAuth2 bearer	No	5,000
TikTok	TikTokStrategy	OAuth2 bearer	No	2,200
Reddit	RedditStrategy	OAuth2 bearer	No	40,000
Twitch	TwitchStrategy	OAuth2 bearer	No	500

---

Environment Variables

Each strategy reads specific environment variables via from_env():

Platform	Variables
Twitter	TWITTER_ACCESS_TOKEN (or TWITTER_ACCESS_TOKEN_KEY)
Bluesky	BLUESKY_IDENTIFIER, BLUESKY_PASSWORD, BLUESKY_HOST (optional)
Mastodon	MASTODON_ACCESS_TOKEN, MASTODON_HOST (optional, defaults to mastodon.social)
LinkedIn	LINKEDIN_ACCESS_TOKEN
Facebook	FACEBOOK_ACCESS_TOKEN, FACEBOOK_PAGE_ID (optional)
Instagram	INSTAGRAM_ACCESS_TOKEN
Discord Bot	DISCORD_BOT_TOKEN, DISCORD_CHANNEL_ID
Discord Webhook	DISCORD_WEBHOOK_URL
Telegram	TELEGRAM_BOT_TOKEN, TELEGRAM_CHAT_ID
Slack	SLACK_TOKEN, SLACK_CHANNEL (optional, defaults to #general)
Dev.to	DEVTO_API_KEY
Nostr	NOSTR_PRIVATE_KEY, NOSTR_RELAYS (comma-separated)
YouTube	YOUTUBE_ACCESS_TOKEN
TikTok	TIKTOK_ACCESS_TOKEN
Reddit	REDDIT_ACCESS_TOKEN, REDDIT_SUBREDDIT (optional)
Twitch	TWITCH_ACCESS_TOKEN, TWITCH_CLIENT_ID

---

Image Support

Attach images using PostOptions:

use crosspost::{PostOptions, ImageEmbed};

let options = PostOptions {
    images: vec![ImageEmbed {
        data: std::fs::read("photo.jpg")?,
        alt: Some("A photo".into()),
        mime_type: Some("image/jpeg".into()),
    }],
};

let results = client.post("Check out this photo!", Some(&options)).await;

• Max 4 images per post
• MIME type auto-detected if not provided
• Supported: JPEG, PNG, GIF
• Image compression utilities available in crosspost::util::images

---

Architecture

The library uses the Strategy pattern. Each platform is a Strategy implementation with credentials baked in at construction time. The Client orchestrates posting to multiple strategies concurrently.

Client::post("message")
    ├── TwitterStrategy::post()   → PostResult::Success / Failure
    ├── BlueskyStrategy::post()   → PostResult::Success / Failure
    └── MastodonStrategy::post()  → PostResult::Success / Failure

One strategy failing does not affect others. Results are collected as Vec<PostResult>.

Server Feature

An optional SaaS server layer is available behind the server feature flag:

[dependencies]
crosspost = { git = "https://github.com/GraftAI-com/crosspost-rs.git", features = ["server"] }

This includes:

• Axum HTTP API with JWT authentication
• SurrealDB for data persistence
• OAuth2 flow handling for platform connections
• Rate limiting (global and per-user)
• Background scheduling for deferred posts
• Token refresh management

Run the server:

cargo run --features server --bin crosspost-server

---

Development

cargo check                                          # Check library
cargo test                                           # Library tests (38)
cargo test --features server                         # All tests (61)
cargo clippy --all-targets -- -D warnings            # Lint library
cargo clippy --all-targets --features server -- -D warnings  # Lint everything
cargo fmt --all -- --check                           # Format check

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License

This project is licensed under the Mozilla Public License 2.0. See LICENSE.

Acknowledgments

• Original crosspost library by Nicholas C. Zakas