Dev tools · alternatives · 2026

24 alternatives to Whirlwind – Async concurrent hashmap for Rust

Hey HN, this is Will and David from Fortress (https://news.ycombinator.com/item?id=41426998). We use a lot of async Rust internally, and created this library out of a need for an async-aware concurrent hashmap since there weren’t many available in the Rust ecosystem. Whirlwind is a sharded HashMap with a fully asynchronous API. Just as dashmap is a replacement for std::sync::RwLock, whirlwind aims to be a replacement for tokio::sync::RwLock. It has a similar design and performance characteristics to dashmap, but seems to perform better in read-heavy workloads with tokio's…

Whirlwind is a sharded concurrent hashmap library for Rust with a fully asynchronous API. Built by developers at Fortress, it provides an async-aware alternative to wrapping hashmaps in tokio synchronization… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Whirlwind – Async concurrent hashmap for Rust launched in 2024; newer entries below may have overtaken it.

1
Rust GUI Library via Flutter▲301
Hi, I made a bridge (https://github.com/fzyzcjy/flutter_rust_bridge v2.0.0) between Flutter and Rust, which auto translates syntaxes like arbitrary types, &mut, async, traits, results, closure (callback), lifetimes, etc. The goal is to make a bridge between the two, seamlessly as if working in one single language. Then, as an example, I showed how to write Rust applications with GUI by utilizing Flutter. That is discussed in the link in details. To play with it, please visit the GitHub repo, or refer to the end of the article for detailed folders and commands. When I…
2024 · cjycode.com · its alternatives →
2
Distributed JMAP and IMAP Servers in Rust▲190
I am happy to announce Stalwart JMAP [1], an open-source JSON Meta Application Protocol server that aims to be scalable, robust and secure. Some of its key features are: - JMAP Core, JMAP Mail and JMAP over WebSocket full compliance. - IMAP4 rev2/1 support via Stalwart IMAP, an imap-to-jmap proxy [2]. - Scalable and fault tolerant: consensus over Raft, node autodiscovery over gossip and read-only replicas. - RocksDB backend with full-text search support in 17 languages. - OAuth 2.0 authorization code and device authorization flows. - Domain Keys Identified Mail (DKIM) message signing. -…
2022 · github.com · its alternatives →
3
Async UI: A Rust UI Library Where Everything is a Future▲173
2022 · wishawa.github.io · its alternatives →
4
Sub-millisecond VM sandboxes using CoW memory forking▲311
I wanted to see how fast an isolated code sandbox could start if I never had to boot a fresh VM. So instead of launching a new microVM per execution, I boot Firecracker once with Python and numpy already loaded, then snapshot the full VM state. Every execution after that creates a new KVM VM backed by a `MAP_PRIVATE` mapping of the snapshot memory, so Linux gives me copy-on-write pages automatically. That means each sandbox starts from an already-running Python process inside a real VM, runs the code, and exits. These are real KVM VMs, not containers: separate guest kernel, separate guest…
Mar 2026 · github.com · its alternatives →
5
Forkrun – NUMA-aware shell parallelizer (50×–400× faster than parallel)▲151
forkrun is the culmination of a 10-year-long journey focused on "how to make shell parallelization fast". What started as a standard "fork jobs in a loop" has turned into a lock-free, CAS-retry-loop-free, SIMD-accelerated, self-tuning, NUMA aware shell-based stream parallelization engine that is (mostly) a drop-in replacement for xargs -P and GNU parallel. On my 14-core/28-thread i9-7940x, forkrun achieves: * 200,000+ batch dispatches/sec (vs ~500 for GNU Parallel) * ~95–99% CPU utilization across all 28 logical cores, even when the workload is non-existant (bash no-ops / `:`)…
Mar 2026 · github.com · its alternatives →
6
Coerce – Actor runtime for Rust using async/await and tokio channels▲155
Actor runtime and distributed systems framework for Rust - LeonHartley/Coerce-rs
2019 · github.com · its alternatives →
7
LocalGPT – A local-first AI assistant in Rust with persistent memory▲331
I built LocalGPT over 4 nights as a Rust reimagining of the OpenClaw assistant pattern (markdown-based persistent memory, autonomous heartbeat tasks, skills system). It compiles to a single ~27MB binary — no Node.js, Docker, or Python required. Key features: - Persistent memory via markdown files (MEMORY, HEARTBEAT, SOUL markdown files) — compatible with OpenClaw's format - Full-text search (SQLite FTS5) + semantic search (local embeddings, no API key needed) - Autonomous heartbeat runner that checks tasks on a configurable interval - CLI + web interface + desktop GUI - Multi-provider:…
Feb 2026 · github.com · its alternatives →
8
A hash array-mapped trie implementation in C▲171
Long-simmering side project that is finally ready to see the light. HAMTs are a cool persistent data structure and implementing one has been a lot of fun. Beyond the code, there is likely some value in the extensive and largely complete implementation docs; basic benchmarks are linked in the README, too. Kind of aiming to be "the libavl for HAMTs". That is obviously a high and aspirational bar but a distinct possibility if it stirs up a little interest and/or contribution. Anyways, it's time for this to go out, collect feedback and maybe even some use outside of toy projects. Let me…
2023 · github.com · its alternatives →
9
Hydrogen, a multithread non-blocking Linux server framework in Rust▲154
Multithreaded, non-blocking Linux server framework in Rust - nathansizemore/hydrogen
2016 · github.com · its alternatives →
10
Await-Tree – Visualize Async Rust Task Execution in Real-Time▲28
Generate accurate and informative tree dumps of asynchronous tasks. - risingwavelabs/await-tree
2025 · github.com · its alternatives →
11
Asynchronous HTTP/2 client for Python 2.7▲94
Tornado HTTP/2 Client. Contribute to vladmunteanu/th2c development by creating an account on GitHub.
2018 · github.com · its alternatives →
12
A tiny library for managing blocking code in Tornado▲15
A declarative library to make blocking code play nicely with the tornado ioloop - bobpoekert/tornado-threadpool
2012 · github.com · its alternatives →
13
A concurrent thread-safe hash map implemented in C++▲17
A concurrent thread-safe hash map implemented in C++ - kshk123/hashMap
2017 · github.com · its alternatives →
14
A fast HNSW implementation in Rust▲111
HNSW implementation in Rust. Reference: https://arxiv.org/ftp/arxiv/papers/1603/1603.09320.pdf - swapneel/hnsw-rust
2024 · github.com · its alternatives →
15
Kameo – Fault-tolerant async actors built on Tokio▲105
Hi HN, I’m excited to share Kameo, a lightweight Rust library that helps you build fault-tolerant, distributed, and asynchronous actors. If you're working on distributed systems, microservices, or real-time applications, Kameo offers a simple yet powerful API for handling concurrency, panic recovery, and remote messaging between nodes. Key Features: - Async Rust: Each actor runs as a separate Tokio task, making concurrency management simple. - Remote Messaging: Seamlessly send messages to actors across different nodes. - Supervision and Fault Tolerance: Create self-healing systems with actor…
2024 · github.com · its alternatives →
16
TinyWasm – A tiny WebAssembly Runtime written in Rust▲172
Show HN: TinyWasm - A tiny WebAssembly Runtime written in Rust Hi HN! I'm excited to share TinyWasm (https://github.com/explodingcamera/tinywasm), a WebAssembly Interpreter I developed for my final university project. The main goal of this project was to deepen my understanding of WebAssembly and interpreter design. TinyWasm successfully passes all the official WebAssembly 1.0 tests and also includes features from future proposals such as like bulk memory operations. Initially more of a research project, TinyWasm focuses on simplicity and portability. It has minimal…
2024 · github.com · its alternatives →
17
Asyncpal: Preemptive concurrency and parallelism for sporadic workloads▲28
Hi HN ! Alex here. I'm excited to show you Asyncpal (https://github.com/pyrustic/asyncpal), a Python library for parallelism [1] and preemptive concurrency [2] tailored for sporadic workloads [3]. I've been working on a private project where it would be convenient to have asynchronous versions of some operations without using `async/await` [4]. Besides `async/await`, which represents cooperative concurrency via the `asyncio` package, Python also provides preemptive concurrency through its `threading` package. Additionally, the `concurrent.futures` package builds…
2024 · github.com · its alternatives →
18
SwimOS Rust – A framework for real-time streaming data applications▲71
2024 · github.com · its alternatives →
19
Unbug – Rust macros for programmatically invoking breakpoints▲96
This project is inspired by some of the asserts in Unreal engine. Due to reliance on core_intrinsics it is necessary to develop using nightly Rust, but there are stubs in place so a production build will not require nightly. I recently released version 0.2 which includes no_std support and adds optional log message arguments to the ensure macro.
2024 · github.com · its alternatives →
20
Bringing multithreading to Python's async event loop▲82
This project explores the integration of multithreading into the asyncio event loop in Python. While this was initially built with enhancing CPU utilization for FastAPI servers in mind, the approach can be used with more general async programs too. If you’re interested in diving deeper into the details, I’ve written a blog post about it here: https://www.neilbotelho.com/blog/multithreaded-async.html
2024 · github.com · its alternatives →
21
Pure C Asynchronous HTTP Framework▲80
Asynchronous C networking library with HTTP server, WebSockets, reverse proxy, HTTP/2 gRPC client, TLS and event loop. - Softmotions/iwnet
2022 · github.com · its alternatives →
22
Lunatic – Actor System for Rust/WebAssembly▲141
Lunatic is an Erlang-inspired runtime for WebAssembly - lunatic-solutions/lunatic
2020 · github.com · its alternatives →
23AF
Apache Fory Rust – 10-20x faster serialization than JSON/Protobuf▲67
Serialization framework with some interesting numbers: 10-20x faster on nested objects than json/protobuf. Technical approach: compile-time codegen (no reflection), compact binary protocol with meta-packing, little-endian layout optimized for modern CPUs. Unique features that other fast serializers don't have: - Cross-language without IDL files (Rust ↔ Python/Java/Go) - Trait object serialization (Box) - Automatic circular reference handling - Schema evolution without coordination Happy to discuss design trade-offs. Benchmarks:…
Oct 2025 · fory.apache.org · its alternatives →
24
Iceoryx2 – Fast IPC Library for Rust, C++, and C▲122
Hello everyone, Today we released iceoryx2 v0.4! iceoryx2 is a service-based inter-process communication (IPC) library designed to make communication between processes as fast as possible - like Unix domain sockets or message queues, but orders of magnitude faster and easier to use. It also comes with advanced features such as circular buffers, history, event notifications, publish-subscribe messaging, and a decentralized architecture with no need for a broker. For example, if you're working in robotics and need to process frames from a camera across multiple processes, iceoryx2 makes it…
2024 · ekxide.io · its alternatives →

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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →