--- url: "https://predictiontoolkit.com/tools/polyfill-rs/" publisher: "PredictionToolkit" dateModified: "2026-11-02" --- [← SDKs & libraries]() SDK # polyfill-rs: Rust CLOB Client and Book Processing polyfill-rs is a Rust/Cargo Polymarket client for CLOB data and authenticated actions, with WebSocket book processing. Its 0.4.x line introduces V2 trading conventions. [**3.5**/ 5Editorial rating]() [Editorial assessment]() [Open the polyfill-rs repository]() github.com **Available on:** API **Pricing:** MIT and Apache-2.0 licensing is offered. No library subscription; infrastructure and venue costs are separate. [Screenshots]() [Explore alternatives]() [SDKs & libraries]() ## Screenshots and interface Product preview1 / 2 The documented scope of optimized processing. ## What is polyfill-rs? Fixed-point representations make internal price processing deterministic, while stored depth can be limited. Choose between the specialized allocation-conscious processor and a general compatibility decoder for mixed messages and unknown events. Zero-allocation claims cover selected warmed existing-level updates and reads, not new books, new levels or removals. Snapshot hashes identify state without logical ordering; distinct hashes at the same timestamp are accepted in arrival order. Published microbenchmarks do not establish another deployment's end-to-end order latency. ### Who it is for - Rust market-data services. - Teams optimizing book processing. - Rust integrations migrating to V2. ## Clients and supported operations - **CLOB client** Read supported market and account data in Rust. - **V2 line** Use 0.4.x authenticated trading conventions. - **Fixed-point books** Convert prices to deterministic internal numbers. - **Specialized processor** Apply updates through an allocation-conscious WebSocket path. - **General decoder** Handle mixed shapes and unknown messages through compatibility parsing. - **Depth controls** Limit stored levels to manage memory. - **Benchmarks** Separate network, decoding and warmed book-update measurements. ## Development workflows ### Build a reader Read a small market page and subscribe to bounded tokens. Select the parser for the feed requirements. ### Measure a bottleneck Separate network time, decoding and book processing before changing the data path. ### Migrate to V2 Read 0.4.x breaking changes and adjust authentication and orders rather than only renaming imports. ## Pricing and total cost MIT and Apache-2.0 licensing is offered. No library subscription; infrastructure and venue costs are separate. ## Installation and configuration 1. Add a supported release to Cargo.toml. 2. Run a public-read example. 3. Choose depth and parser. 4. Check snapshots and incremental updates. 5. Review V2 authentication before private actions. 6. Benchmark the actual deployment workload. ## Useful links ### What to check - The general parser is not the specialized zero-allocation path. - A snapshot hash is not a sequence number. - Same-time snapshots with different hashes follow arrival order. - Microbenchmarks do not establish end-to-end order latency. A closer look ## Ratings & reviews Editorial rating **3.5**/ 5 0 user reviews PredictionToolkit editorial ### Our take on polyfill-rs Typed Rust requests and narrowly scoped performance paths suit specialist integrations. Version changes, snapshot ordering and benchmark limits require careful review. **Assessment criteria:** Task usefulness, documented scope, setup clarity, and access and cost transparency. **Assessment date:** 2026-10-01 **Documentation reviewed:** 2026-10-01 Documentation-based assessment. [How we rate]() ### User reviews 0 The main score switches to user ratings after 5 published reviews. **Be the first to share your experience** A specific example helps the next person choose the right tool. ## Related tools [Browse category]() ![Official @polymarket/client TypeScript quickstart]() ![@polymarket/client logo]()[@polymarket/client]() SDK**4.0**Editorial Build typed Polymarket apps with public reads, resumable scans, real-time topics and separate authenticated actions. - Language TypeScript · JavaScript Compare the official TypeScript client. ![NautilusTrader Polymarket adapter scope and integration-guide entry]() ![NautilusTrader logo]()[NautilusTrader]() SDK**4.0**Editorial Receive native market events and manage signed orders, reconciliation and resolution in one trading framework. - Language Python · Rust Compare a larger Rust/Python trading framework. ![Polymarket.Net features and target frameworks]() [Polymarket.Net]() SDK**4.0**Editorial Integrate Polymarket in C# with typed REST, socket callbacks, local books and distinct account configuration. - Language C# - Access API Compare a .NET client. ## Frequently asked questions about polyfill-rs ### Is every operation allocation-free? No. Only selected warmed updates and reads have that documented scope. ### Can a hash order snapshots? No. It distinguishes state, not ordering among different snapshots. ### Does 0.4.x preserve old authenticated flows? No. It introduces V2-related breaking changes. ### Which measurement explains API slowdown? Separate transport, decoding and local book updates. In this profile