AI · alternatives · 2026
24 alternatives to I built a one-prompt hackathon platform, free entry, sponsored prizes
One prompt, one AI model, one shot. Write a single prompt, run it once with any model, and the result is your entry. Six winners take a GTA VI copy (first place a PS5 too), one of them chosen by community vote. Winners announced at the World Models & GenAI Mixer @ SIGGRAPH in LA on July 20.
1shotchallenge.ai is a hackathon platform where participants compete using a single prompt. The platform offers free entry and is sponsored by partners who provide prizes for winners. It is designed for developers and… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes.
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Agent Arena▲348Creator here. I built Agent Arena to answer a question that kept bugging me: when AI agents browse the web autonomously, how easily can they be manipulated by hidden instructions? How it works: 1. Send your AI agent to ref.jock.pl/modern-web (looks like a harmless web dev cheat sheet) 2. Ask it to summarize the page 3. Paste its response into the scorecard at wiz.jock.pl/experiments/agent-arena/ The page is loaded with 10 hidden prompt injection attacks -- HTML comments, white-on-white text, zero-width Unicode, data attributes, etc. Most agents fall for at least a few.…
Jun 2026 · arena42.ai · its alternatives →
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Inworld Arcade▲189Do our AI characters pass the Turing test, you tell us
2022 · inworld.ai · its alternatives →
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Playground▲198We build AI agents to find vulnerabilities in other AI agents. The playground started as an internal tool that we used to test our own offensive agent Nyx. But we realised that hacking an AI is about have as wide a distribution of attacks as possible, especially those which aren't in the distribution of the models. So we are launching playground as a platform to crowdsource agent jailbreaks. And although hacking AI is super fun and we are sure people will do it for free, we want to reward those who help us push forward the offensive frontier of AI. So we are committing $100K in prizes over…
Jul 2026 · playground.fabraix.com · its alternatives →
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Code Arena▲272Prompt once. Compare multiple AI-built apps for free.
Feb 2026 · arena.ai · its alternatives →
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Scheduled agents fail in four ways: silent skips, tokens burned on nothing, no memory between runs, and needing your laptop awake. Routines answers all four.
2023 · octomind.run · its alternatives →
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A global hackathon for the open AI future
Jun 2026 · decentralizeai.tech · its alternatives →
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Dear Hacker News, I'm kindly asking for your participation in the open beta for my AI-managed mini-games website. Thank you in advance! For a limited time window, I'm setting the all-free feature flag to true. I hope you have a lot of fun exploring the AI's sense for games! Here and there, I tweaked it to help with visual consistency. I would be deeply grateful if you opted into analytics. $2,300 in API tokens... Cheers!
Jun 2026 · minigames.world · its alternatives →
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Build a viral giveaway campaign in minutes for your brand!
2023 · kickofflabs.com · its alternatives →
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Art by an AI▲128The daily prompt competition. Winning prompts become art!
2021 · artbyanai.com · its alternatives →
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prompts.chat▲63Discover, collect, and share the best AI prompts for ChatGPT, Claude, Gemini, and more. Join the largest community of AI prompt engineers and creators.
Dec 2025 · prompts.chat · its alternatives →
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I built a March Madness bracket challenge for AI agents, not humans. The human prompts their agent with the URL, and the agent reads the API docs, registers itself, picks all 63 games, and submits a bracket autonomously. A leaderboard tracks which AI picks the best bracket through the tournament. The interesting design problem was building for an agent-first user. I came up with a solution where Agents who hit the homepage receive plain-text API instructions and Humans get the normal visual site. Early on I found most agents were trying to use Playwright to browse the site instead of just…
Mar 2026 · bracketmadness.ai · its alternatives →
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Ziva.sh ▲82Hey everyone! Wanted to show off a little side project I've been working on. A lot of people have been using AI to one-shot games, but they're often quite buggy - glitchy graphics, collisions aren't setup, or regressions in earlier levels. With an AI playtester in the loop, I've been able to one-shot games like Candy Crush or Crossy Road that would previously have bugs like cut-off UIs or stuck retries. The way it works basically goes like this: 1/ The playtester starts by reading the code to understand what its parent AI is asking it to play, and to decide what breakpoints, hooks and…
Feb 2026 · ziva.sh · its alternatives →
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chat.win▲8Prompting arena site where users win money breaking prompts and earn money creating them. Alternative to https://hackaprompt.com / https://app.grayswan.ai/arena, Open to feedback/improvements/bugs. - Uses USDC on polygon just like polymarket. - Fun and a good way to actually prove your prompting abilities. - See every attempt live as it's happening and improve from what your opponents are doing.
2025 · chat.win · its alternatives →
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Hi HN, I've been experimenting on-and-off over the years trying to automatically generate crosswords [1]. Recently I've been feeling like my results are good enough that I want to share them and see what other people think. I'm not trying to claim that these could appear in, say, the NYT in their current state, but honestly the velocity of progress makes me feel like I will inevitably be able to automatically generate NYT-quality crosswords within just a year or so. A write-up is here: https://abstractnonsense.com/crosswords.html And you can play the crosswords here:…
2024 · abstractnonsense.com · its alternatives →
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Compare AI models side-by-side on same prompt
Feb 2026 · testaimodels.com · its alternatives →
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Also inspired by this HN submission: https://www.chiark.greenend.org.uk/~sgtatham/quasiblog/findl... The model is gpt-4o-mini-2024-07-18.
2024 · app4.hc11.org · its alternatives →
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Hey HN! We’ve been experimenting with integrating multimodal models directly into creative workflows, and ended up building an AI-first image editor using OpenAI’s new `gpt-image-1` (from GPT-4o) inside our SDK. Instead of prompting in ChatGPT and pasting outputs into a design tool, this lets you generate, edit, and remix images all in one canvas. This allows for really interesting new workflows, like quickly mixing multiple images, or creating visual prompts by using annotations and reference on the canvas. Some key details: - Built with our plugin system in CE.SDK (CreativeEditor SDK) -…
2025 · img.ly · its alternatives →
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Free prompts market for multi-AI image generator
2024 · artiversehub.ai · its alternatives →
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Hi HN, I built Prompt Builder (https://www.promptbuilder.space/) because I was frustrated managing complex AI prompts in plain text boxes. The core idea: instead of one giant textarea, you compose prompts from draggable, reorderable blocks. Each block can have its own XML/custom tags, visibility toggles (so you can A/B test sections), and duplicates. Key technical details: - Live compiled preview: the right pane shows the exact string being sent, updating as you drag/toggle blocks - Dynamic variables: define {{var_name}} once, use across blocks, change in one…
Aug 2026 · promptbuilder.space · its alternatives →
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Hey HN, I'm Damiano Rodriguez, and I've been working solo on a project called Caisual Games. It's a free platform where anyone can create web games just by describing them with their voice. Here's how it works: You simply describe your game idea ("Make a cookie clicker game with 5 upgrades"), and the platform generates a playable web game in seconds using HTML and JavaScript. There's no coding required and no downloads needed—you can create and play directly in your browser. What's more, anyone can improve a published game, fostering a collaborative environment for game creation. The…
2024 · caisual.com · its alternatives →
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Tired of vague AI answers? Get better results from ChatGPT with PromptQuick. Download your free sample!
2025 · promptquick.ai · its alternatives →
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