# Crossbar ## Crossbar: Switchboard's Utility Server Crossbar is a high-performance utility server implemented in Rust, designed to simplify interactions with the Switchboard network. It provides essential functionalities for simulating and resolving feeds across various blockchains. Crossbar comes with a set of useful utility functions for resolving feeds on all chains with active Switchboard deployments, IPFS utilities for storing and fetching jobs, and built-in simulation capabilities for constantly fetching feed updates for liquidators and other bots. > **Note**: The Rust version includes built-in simulation and no longer requires a separate Task Runner Simulator service. > Running your own instance of Crossbar is highly recommended for user interfaces and bots that require frequent price simulations. Refer to [Run Crossbar with Docker Compose ](/tooling/crossbar/run-crossbar-with-docker-compose.md)for instructions on setting up your own Crossbar instance. ### Key Features Crossbar aims to streamline the Switchboard experience, offering the following core functionalities: * **Fetch Feeds by Feed Hash:** Retrieve a feed's job definitions and queue in JSON format using its unique feed hash (content identifier). * **Store Jobs:** Store feed definitions using your configured IPFS node (requires Piñata credentials or a Kubo node). * **Simulate Feeds by Feed Hash:** Simulate multiple feeds simultaneously using their feed hashes, enabling off-chain tracking of custom price feeds for bot automation. ### Blockchain-Specific Features Crossbar provides tailored features for specific blockchains: **Solana and Aptos/Sui:** * **Fetch Encoded Update Instructions:** Retrieve update instructions from live oracles for Solana feeds (available on devnet and mainnet). * **Fetch Simulated Results for Feeds:** Fetch current prices for feeds. This is a useful feature for tracking custom price feeds off-chain, for triggering an action that the bots can use. **Ethereum Virtual Machine (EVM):** * **Fetch Encoded Updates:** Obtain an encoded update for a feed to submit on-chain via a contract explorer (like Etherscan), eliminating the need to include feed definitions directly in your frontend. * **Settle Randomness:** Fetch a settlement message for resolving randomness requests when using Switchboard's EVM Randomness features. ### Rust Implementation Benefits The Rust implementation provides several advantages: * **High Performance:** Built with actix-web for maximum throughput * **Built-in Simulation:** No separate Task Runner Simulator required * **WebSocket Support:** Real-time data streaming capabilities * **Memory Efficiency:** Optimized for high concurrent connections * **Simplified Deployment:** Single binary with minimal dependencies ### Environment Variables All environment variables are optional and have sensible defaults: **Core Configuration:** * `PORT` (default: 8080) - HTTP server port * `WS_PORT` (default: 8081) - WebSocket server port * `DISABLE_API` (default: false) - Disable HTTP API entirely **Performance:** * `BROADCAST_WORKER_THREADS` (default: 32) - Tokio worker threads * `SIMULATION_CACHE_TTL_SECONDS` (default: 3) - Cache TTL * `DISABLE_CACHE` (default: false) - Disable caching **Blockchain RPCs (Recommended):** * `SOLANA_MAINNET_RPC` - Solana mainnet RPC * `SOLANA_DEVNET_RPC` - Solana devnet RPC **IPFS (Optional):** * `IPFS_GATEWAY_URL` (default: ) - IPFS gateway * `PINATA_JWT_KEY` - Pinata storage key * `KUBO_URL` - Local IPFS node For a complete list of environment variables, see the [Docker Compose guide](/tooling/crossbar/run-crossbar-with-docker-compose.md#environment-variables-reference). #### Public Instance of Crossbar While a public instance is available for quick testing, running your own Crossbar instance is highly recommended. Switchboard oracles are heavily rate-limited by IP address, so using a dedicated instance prevents disruptions. * **Public Instance:** #### Public Rate Limits (as of March 3, 2026) The public Crossbar endpoint has multiple limit layers. The key limits to plan around are: * **Network-level oracle request budget:** default `20 RPS` per user wallet for Switchboard requests; higher limits are available with `svSWTCH` stake. See [The Switchboard NCN](/how-it-works/switchboard-protocol/re-staking/the-switchboard-ncn.md). * **Public edge throttling:** `https://crossbar.switchboard.xyz` enforces additional IP-based throttling and can return `429 Too Many Requests` under burst traffic (especially for `/updates/*` routes). * **Surge connection caps:** managed Surge subscriptions have explicit connection limits by plan (`Plug: 1`, `Pro: 10`, `Enterprise: 15`). See [Surge pricing and limits](/docs-by-chain/solana-svm/surge.md). Practical guidance: * Treat public Crossbar as **best-effort** for development and low-volume usage. * Back off exponentially with jitter on `429` responses. * For production bots/frontends, self-host Crossbar to remove public edge contention. **Examples:** * **Job Definition Fetch:** * **EVM Oracle Fetch (Core Mainnet):** ### Advanced * [Crossbar API Endpoints](/tooling/crossbar/api-endpoints.md) — complete endpoint reference by route group. * [Surge Gateway Protocol](/tooling/crossbar/gateway-protocol.md) — HTTP + WebSocket protocol for custom Surge clients. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.switchboard.xyz/tooling/crossbar.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.