# Web3 hackathon demo video: the wallet is the shot that gives you away Source: https://flexdger.com/blog/web3-hackathon-demo-video Updated: 2026-10-17 Published: 2026-10-17 Topic: Video and creators (https://flexdger.com/blog/creators) > Make a web3 hackathon demo video: event length and recording rules, a three-minute running order, and a demo wallet setup that keeps your address private. A judge pauses your video on a wallet pop-up and copies the address. This guide covers the length and recording rules of big web3 events, a script that fits them, and a way to set up the wallet so the shot helps your pitch instead of exposing you. **Short answer:** Show the working project in two to four minutes, recorded on a computer, with your own voice. ETHGlobal rejects videos outside that range and bans sped-up footage and AI voiceovers. Run the live part on a testnet from a dedicated demo wallet and never your personal one, since an EVM account has the same address on every network. ## The pause button is the judge's best tool Picture a judge with forty submissions to get through. Your video plays, a signing prompt opens, and with one click the judge freezes the frame on a long 0x address. Maybe it is only curiosity. If the account is your everyday one, it just handed a stranger your balances and your history. Most of what follows is about that moment, because the wallet appears in nearly every web3 demo. Before getting to it, here is what the events themselves demand, since a video that breaks the rules never gets as far as being judged. ## What the big events ask for **ETHOnline 2026 (ETHGlobal).** A demo video, plus a GitHub repository, Figma files or an equivalent that shows the work. The video must run between 2 and 4 minutes, and uploads outside that window are rejected. Other rules: at least 720p, no sped-up footage, no phone recordings, no music with on-screen text in place of a voice, and no text-to-speech or AI voiceover. Judging uses five criteria: technicality, originality, practicality, usability and a wow factor. ETHGlobal also warns that large single commits or missing histories can lead to disqualification. **Colosseum hackathons (Solana).** Two videos: a pitch of three minutes at the most, and a technical demo of 2 to 3 minutes that explains design choices and the tech stack. Judges need access to every document and repository you link. **Devpost-hosted events.** Devpost describes the video as among the first things judges open, and its collected advice from past participants is to make it a demo, not a slide deck. The link must be a YouTube, Vimeo or Youku URL set so that anyone can watch. The common thread: working code that judges can trace, explained by a human voice. ## Choosing the wallet for the shot Three accounts are within easy reach, and each has a weakness. - **Your daily wallet.** MetaMask's help pages explain that an EVM account keeps one address on every network, so recording a testnet flow from it still shows your mainnet address, with whatever it holds and has done. - **The testnet wallet from the whole weekend.** Safe, but messy on camera: faucet leftovers, tokens from other teams' projects, labels like SepoliaETH. Faucets also ration supply. Alchemy's Sepolia faucet pays 0.1 ETH once per 24 hours, and only to an address that holds at least 0.001 ETH on mainnet. That requirement is what tempts people into requesting test funds with their main address. - **A fresh wallet.** Clean, and empty. A zero balance carries no story, so the before-picture of your pitch has nothing in it. Putting a genuine wallet in a public video carries real risk. [Why showing crypto online makes you a target](https://flexdger.com/blog/wrench-attacks-crypto-creators) collects what security firms tell people who appear on camera, and [screen sharing a wallet on a call](https://flexdger.com/blog/screen-share-crypto-wallet) handles the live-pitch version of the same problem. ## Building a demo wallet, step by step 1. Generate a new account from a new recovery phrase. Never import your personal phrase into the browser used for recording. 2. Fund it on the testnet your contracts target. Ethereum.org calls Sepolia the recommended default for application development, and Holesky has been deprecated since September 2025. 3. Rename the account to "Demo" and hide stray tokens so the list shows only what your project touches. 4. Use a clean browser profile: no bookmarks bar, no extra extensions, no tabs signed in to personal accounts. 5. Mute notifications and record on the computer itself, since ETHGlobal does not take phone recordings. 6. Export at 1080p, never under 720p. If you are over the limit, cut footage. Do not speed it up. 7. Scrub the finished file frame by frame for an address, an email or a document you did not mean to show. Resolution, cursor movement and other capture details are in [recording a wallet screen video](https://flexdger.com/blog/larp-wallet-tutorial#record). ## A three-minute running order Three minutes holds a lot if each beat has a single job. Write the script early and read it aloud against a clock. 1. **0:00 to 0:20, the user.** One frame that sets the scene: who they are and what they have or want. 2. **0:20 to 0:35, the product.** One sentence, over your app's first screen. 3. **0:35 to 2:05, the run.** The project working on a testnet, in one or two unbroken takes, with input that visibly changes the numbers. A demo whose figures never move looks like a mockup. 4. **2:05 to 2:40, the engine room.** The contract on a block explorer, the architecture, the hard problem you solved. A deployed address that judges can open is the quickest proof the on-chain part exists. 5. **2:40 to 3:00, what follows.** Three roadmap points and the team. ### Let the signature prompt breathe Usability is a scoring criterion, and in web3 the wallet prompt is part of the experience. Keep the signature or transaction request up long enough to read, say what the user is approving in one line, and then show the outcome: the new state in your app and the confirmed transaction on the explorer. When the testnet drags, trim the wait in the edit. Speeding up is banned, and a video that jump-cuts past every prompt makes judges wonder whether the on-chain half works. ## Story frames versus the product The opening of the running order needs a picture of the user: a wallet with some stablecoins and a little ETH that your app is about to put to work. The ending may show the same wallet afterward. Those are story frames and not the product. A testnet wallet reading 0.0731 SepoliaETH plus three tokens from other projects muddles them, and your personal wallet endangers you. Some teams use a different tool for these frames. A larp wallet, or crypto wallet app simulator, produces a believable wallet screen from figures you type, for a video, a sketch, a pitch deck or a demo. It holds nothing and reads no chain. Type the balances your story needs, say 1,250 USDC and 0.8 ETH, and capture the screen. Nothing in it leads to an address or a history. We make one of these apps, [Flexdger Wallet](https://flexdger.com/guides/larp-wallet), and [what a crypto wallet simulator is](https://flexdger.com/blog/crypto-wallet-simulator) explains what the category does and where it stops. The rule that keeps it honest: story frames illustrate the user, and everything that shows what you built is your own project, running on testnet and recorded live. Judges score technicality and practicality, so they want to see real code do real things. If your project outlives the weekend, [app demo videos for crypto products](https://flexdger.com/blog/crypto-app-demo-video) carries the same split into launch and investor videos. ## Illustration, never evidence A simulated wallet frame is an illustration. Tag it with a small "Illustration" label, keep it out of the live segment, and never use it to show a feature you did not build, a transaction that never happened, or traction such as deposits or users. A mockup proves nothing about anyone's holdings or about your code. Passing it off as real holdings, real traction or evidence of any sort is deception, and our [terms of use](https://flexdger.com/terms) forbid it. Flexdger Wallet is not affiliated with MetaMask or any wallet named here. Their names appear here only to describe their rules and tools. Labeled sample screens are the honest version of showing a product early; the dishonest version has a name in startup circles, [tech larping](https://flexdger.com/blog/tech-larping-meaning). ## Sources - [ETHGlobal: ETHOnline 2026 event details, with submission, demo video and judging rules](https://ethglobal.com/events/ethonline2026/info/details), 2026 - [Colosseum: perfecting your hackathon submission](https://blog.colosseum.com/perfecting-your-hackathon-submission/), May 8, 2025 - [Devpost: 6 tips for making a winning hackathon demo video](https://info.devpost.com/blog/6-tips-for-making-a-hackathon-demo-video) - [Devpost Help Center: uploading a demo video](https://help.devpost.com/article/85-uploading-a-demo-video), September 25, 2026 - [ethereum.org: networks, testnets and faucets](https://ethereum.org/en/developers/docs/networks/), September 23, 2026 - [Alchemy: Ethereum Sepolia faucet](https://www.alchemy.com/faucets/ethereum-sepolia), 2026 - [MetaMask Support: the Ethereum address format and why it matters](https://support.metamask.io/more-web3/learn/the-ethereum-address-format-and-why-it-matters-when-using-metamask/) ## Questions ### What running time should a hackathon video have? Whatever the event enforces. ETHOnline 2026 demanded 2 to 4 minutes and refused uploads outside it. Colosseum wants a pitch of three minutes or less and a separate technical demo of 2 to 3 minutes. Whatever the cap, keep the heart of the demo in the opening two or three minutes. ### What belongs in the video? A user's problem in a sentence, your project in a sentence, the thing running on real input, a quick look at the deployed contract on a block explorer, and the next step. Devpost's participants say it should be a demo of the project in action, not a slide deck. ### How should I get ready the night before? Time a written script aloud, fund a dedicated demo wallet on the testnet your contracts live on, record from a clean browser profile with notifications muted, keep a spare take, and scrub the export frame by frame for any address, email or document you did not intend to show. ### Is a mockup allowed in the video? Only as a clearly labeled context frame, for instance a user's balance before your app does anything. Anything that shows what you built has to be real and recorded live: judges score technicality and practicality, and ETHGlobal warns that large single commits or missing histories can disqualify an entry. ### Why not just use my everyday wallet? The video is public and anyone can pause on the address and look it up. Because Ethereum and other EVM networks give an account the same address everywhere, a testnet session from your main account still reveals your mainnet address, balances and history. Make a separate demo wallet.