Alternatives
Products that do what Pure Effect – Reproduce production bugs on your laptop without a DB does
Hi HN, I think it's safe to say that the majority of developers don't give a second thought to writing code with I/O tangled in business logic. It's all too common to see code like: const user = findUser(email); if (!user) await saveUser(user); Now, you may ask: what's the big deal? When we write code like this, two things happen: 1. It gets harder to debug production bugs. Unless you have the exact same database and remote API services to connect to, you may fail to reproduce the bug. 2. You have to use mocks and fakes in your tests, or use test containers, which only help somewhat,…
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We are building a VM that helps you simulate realistic production conditions, model latencies, different interleaving, user requests, and find bugs. Every non-deterministic property is turned into a knob you or a coding agent can control. We have helped teams perfectly reproduce support incidents and found bugs in some of the world's most well tested software (including a database).
Jun 2026 · workers.io
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Logging and tools like Sentry are a thing of the past. A while back on a night out in northern Norway, I had to start debugging a critical production bug that broke the payment flow of my SaaS product. I had limited time to fix the bug or I would have lost about ~1K profit. Super stressful. I had logging and Sentry in place, but neither helped me reproduce or find the root cause of the bug. Ever since, I started thinking; why can’t we just have a tool that you setup once, and that allows us to reproduce every function call and function that the user ran before the bug? This is how the idea…
2023 · useflytrap.com
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Bugpilot▲94Turn errors, DOM, + screenshots into an AI-ready Markdown
Jun 2026 · chromewebstore.google.com
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After a pretty rough gig experience, I wanted to remind myself that I was a vaguely capable developer. I had recently jumped on the Rust train and wanted a Rust equivalent of React that is more performant and easier to work with. I also wondered if I could effectively eject Javascript. This project came from that... Nectar is a programming language that compiles your entire app, logic, state, and rendering, to WebAssembly. JavaScript is reduced to a roughly 10 KB syscall layer that only bridges WASM to the DOM. The origin: I set out to get React-style ergonomics with better performance, and…
Jul 2026 · buildnectar.com
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I built FixBugs, an agent that ingests the rich context surrounding production bugs to reproduce them in a sandbox and generate verified fixes. It's available in the form of a self-hosted VSCode extension and as a Github app: VSCode Extension: https://fixbugs.ai/go/vscode-extension - full code and data privacy. - zero data retention models opted out of training. GitHub App: https://fixbugs.ai/go/github-app - we do access your code temporarily. - pick a repo to install FixBugs on. What motivated me to build FixBugs were my years being on-call at Google…
Jul 2026 · fixbugs.ai
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Hi! I wanted to understand more about databases' internals so I wrote one from scratch. It has a T-SQL inspired syntax with support for functions and procedures. It can be used stand-alone as a SQL engine or with a server allowing for persistence and replication to other connected clients. Performance are nothing near sqlite of course but that's beside the point. It’s a small database engine that can run in a web app as a way to store session data, do small calculations on a web worker, store the document/data the user is editing or facilitate “multiplayer” feature by broadcasting the…
2022 · github.com
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Hey everyone! Some time ago I was analyzing why React apps are so hard to optimize, and came to a conclusion that the lack of atomic updates is the culprit. I made an experimental library which basically updates everything in place directly in HTML. At some point I became aware that Solidjs exists, which is a very similar idea, but at the end of the day I realized my approach to API is quite different and warrants the existence of my library (my state primitive allows selector subscriptions, array iterators return a state primitive with the element, allowing to never re-render the whole…
2024 · github.com
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Hi HN, I'm Mathieu and two days ago I ran into a YouTube video about Effect ("a powerful TypeScript framework that provides a fully-fledged functional effect system with a rich standard library"). This made me so exited that I wanted to build something with it and this is the result! Effect UI - A reactive UI framework completely build with Effect. Reactive properties are SubscriptionRefs which make fine-grained reactivity possible (like in SolidJS, no re-renders like in React). Components are just Effects, which makes dependency injection of themes, clients and stores possible by using…
2025 · github.com
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I created Pylon to make it easier to move from hobby projects to full production apps. When I work on hobby projects, I usually use React or Next.js because they are quick to set up and easy to deploy on Vercel. For production apps, I separate the frontend and backend, then deploy the backend on AWS. But setting up a full backend on AWS can be complex and costly, especially for simple apps. Pylon is a full-stack, real-time framework that includes server-rendered React, TypeScript functions, entities, policies, real-time sync, built-in authentication, and support for background and scheduled…
Jul 2026 · pylonsync.com
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Hi HN, I built *CodeDrift*, a CLI tool that detects bugs commonly introduced by AI coding assistants like Copilot, Cursor and ChatGPT. Over the last year I noticed that AI tools often generate code that compiles correctly, passes linting and looks reasonable in code review but still contains subtle issues. Some common examples I kept seeing: * async `forEach` loops that never await promises * missing authorization checks (IDOR) * hallucinated dependencies that don’t exist * stack traces leaking sensitive information * request data used without validation These bugs often slip past ESLint,…
Mar 2026 · npmjs.com
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Hi all, I've been working on this devtool for 1 month now for myself at first and I'll be curious to see if it's something that could work for you as well. So basically, it detects bugs in your website in production from real user sessions, an llm clusters them by severity and it provides the complete context of the issue that you can copy-paste into your coding agent to fix it in one go. Why did I create it? I've been shipping fast with tools like Cursor and Claude Code. The problem? When bugs happen in production, these tools have zero context about what actually went wrong. Sentry is…
Nov 2025 · sonarly.dev
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2016 · github.com
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I participated in the Nvidia + Vercel 2 hour hackathon in SF tonight, and built something I've wanted, but hadn't tried building. I implemented an MCP Server and VS Code extension to allow Claude Desktop to place breakpoints, step through code, and execute expressions (assuming language support). So you can ask it a question that requires actually stepping through the code and now it can actually do that - check values for you, etc. It's _definitely_ not perfect. Have improvements? Please make a PR!
2025 · github.com
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2018 · medium.com
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Hey friends, I've been tinkering with a project and wanted to get some feedback from you all. It's a React-based no-code test case workflow editor aimed at making API testing easier for both QA folks and developers. What It Does: No-Code Testing: Makes it easy for QA people who aren’t into coding and helps developers collaborate. Supports Complex Workflows: Can handle sophisticated environments and workflows. Easy Result Sharing: Makes it simple to share test results and troubleshoot. I've put together a playground where you can mess around with it without signing up:…
2024 · reapi.com
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Hey HN — I'm Michael from Decipher (https://getdecipher.com). We build infrastructure for autonomously generating and maintaining end-to-end tests. Today we’re launching our Claude Code integration. We built this because as teams ship more code, especially with coding agents, they need more regression coverage. Claude can already generate a decent Playwright file from a repo and prompt. That solves first-draft generation. It does not solve repeatability. A generated test is still a static guess. The real problems start when it meets the live app: the browser is logged out, a modal…
Mar 2026 · docs.getdecipher.com
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