Welcome to the Proof of Usefulness Hackathon spotlight, curated by HackerNoon’s editors to showcase noteworthy tech solutions to real-world problems. Whether you’re a solopreneur, part of an early-stage startup, or a developer building something that truly matters, the Proof of Usefulness Hackathon is your chance to test your product’s utility, get featured on HackerNoon, and compete for $150k+ in prizes. Submit your project to get started!Today we are interviewing Cemali Gencer, the creator behind Freshist. Freshist is a calm, 3.7 MB native macOS cleaner designed to free up disk space, fully uninstall apps, and monitor system health without subscriptions or telemetry.What does Freshist do? And why is now the time for it to exist?Freshist is a calm, 3.7 MB native macOS cleaner that frees up disk space and keeps your Mac healthy: cleanup, complete app uninstall, storage analysis, and live system monitoring in one app. No subscription, no telemetry, and nothing is ever deleted without your say — made for Mac users and developers tired of heavy, subscription cleaners. Now’s a good time for Freshist to exist because users are increasingly frustrated with bloated, subscription-based utilities and invasive telemetry, demanding tools that are both effective and privacy-respecting.What is your traction to date?Freshist's website (fresh.ist) currently reaches about 5,000 visitors per month, growing organically with no paid advertising. That traffic is high-intent — people actively looking to reclaim disk space or move off a subscription-based Mac cleaner — and it converts into downloads of the notarized DMG and free-trial starts. The app is also listed across several Mac software directories, which adds incremental reach on top of the site.Combined, Freshist currently reaches roughly 5000 people/month, primarily through the website, Product Hunt, and word of mouth. It's a one-time-purchase macOS utility, so reach is early but the audience is high-intent (people actively looking to reclaim disk space).Who does Freshist serve?Freshist is for three overlapping groups. First, everyday Mac users who want to free up disk space and keep their Mac healthy without paying a monthly subscription or dealing with fear-marketing and upsells. Second, and most strongly, developers — people drowning in Xcode DerivedData, iOS device-support files, and npm/pnpm, Docker, Gradle, CocoaPods and Homebrew caches, which quietly eat tens of gigabytes; Freshist surfaces these as their own categories so they can clear them safely in one place. Third, privacy-conscious users who refuse telemetry and accounts and want a tool that provably keeps everything on-device. In short: anyone who wants a fast, honest, one-time-purchase alternative to bloated, subscription-based cleaners.What technologies were used in the making of Freshist? And why did you choose ones most essential to your tech stack?Freshist is built natively for macOS using Swift and SwiftUI, leveraging modern frameworks like Swift Concurrency and XPC to ensure a fast, lightweight 3.7 MB footprint. The tech stack also incorporates deep macOS API integration for system monitoring, Sparkle for seamless updates, and Cloudflare Workers, along with strict code signing and notarization, to prioritize user privacy and system security.Freshist earned a 58.28 proof of usefulness score (https://proofofusefulness.com/report/freshist) - how do you feel about that? Needs reassessment or just right?Honestly, it feels fair for where Freshist is. The score is held back by reach and traction, not by usefulness — which is exactly right, because I launched recently and haven't pushed distribution yet. I'd rather have an honest 58 that reflects real early numbers than an inflated one. I treat it as a baseline: the product and its safety model are already strong, so the criterion I expect to climb is adoption — and that's what I'm working on now.What excites you about this Freshist's potential usefulness?What excites me most is proving that a Mac cleaner can be genuinely trustworthy. This entire category runs on the opposite — subscriptions, fear-marketing, telemetry, and black boxes with delete access to your whole disk. Freshist's bet is that people actually want the calm version: a tool that shows you everything before it touches it, moves files to the Trash instead of deleting them, keeps every byte on your machine, and asks for money exactly once. If that resonates, it points to something bigger than one app — that "useful and honest" can beat "flashy and extractive."The biggest upside is the developer angle. A single Xcode, npm, and Docker cleanup can reclaim tens of gigabytes, and those users share their results loudly. And because safety is enforced structurally — the build won't even compile if a permanent-delete API sneaks in outside SafetyKit — I can keep making Freshist more capable without ever making it more dangerous. Real utility plus provable safety, in 3.7 MB: that's what makes me think it can matter far beyond its size.Walk us through your most concrete evidence of usefulness. I'd rather be honest than impressive here, so I won't quote a big user count — Freshist is early. The concrete, non-vanity data point is what a single run actually produces. On a typical Mac, and especially a developer's, Freshist surfaces tens of gigabytes of genuinely reclaimable cache and build artifacts — Xcode DerivedData, iOS device-support files, Docker, npm/pnpm, Gradle and the rest — and shows every byte before touching anything. The proof of need isn't that people visit the site; it's that when someone runs the free scan and sees that number sitting on their own disk, they clear it. Nobody discovers tens of gigabytes they didn't know they were losing and walks away indifferent. That "run it once, see the real number, act on it" behavior is the clearest evidence I have that the need is real, not manufactured.How do you measure genuine user adoption versus "tourists" who sign up but never return? Two things shape my answer honestly: Freshist is one-time-purchase, so there are no monthly logins to count, and it has no telemetry, so I've deliberately given up the usual analytics. I measure adoption indirectly and privately — update-adoption through the Sparkle appcast (are installs still pulling new versions weeks after purchase?), license activations across the machines a single license allows (installing on a second or third Mac is a strong "keeper" signal), and the volume and specificity of feature requests from people clearly using it repeatedly. A cleaner is periodic by nature — the "return visit" is next month's cleanup — so the retention story is whether the app stays installed and gets reopened, and those signals say it does. I accept a little less measurement in exchange for not surveilling users; that trade-off is the product.If we re-score your project in 12 months, which criterion will show the biggest improvement, and what are you doing right now to make that happen?Audience Reach and Traction — my weakest criteria today — will show the biggest jump; the product and safety are already solid, distribution is what's early. Right now I'm building channels that compound: a "CleanMyMac alternative" comparison/SEO page for high-intent search, a Homebrew cask for power-user discovery, an honest developer-story launch on r/macapps, and outreach to Mac-focused YouTubers with free licenses. I'm also exploring a small free tool as a top-of-funnel, so growth doesn't depend on me personally promoting it.How Did You Hear About HackerNoon?Through the Proof of Usefulness Hackathon invitation emailWith 5,000 monthly organic visitors already reaching your site, what specific channels or communities have been the most effective at driving these high-intent users to download the free trial?Mostly organic search, plus the Product Hunt launch, with the rest direct and word-of-mouth.You mentioned planning to target high-intent SEO terms like "CleanMyMac alternative" and engaging with communities like r/macapps. How do you plan to scale these efforts as Freshist grows beyond its early stages?The plan is turning one-off launches into repeatable, compounding content. On SEO: a family of high-intent comparison pages ("CleanMyMac alternative", "free up disk space on Mac", "uninstall Mac apps completely"), with the HackerNoon piece as an authoritative backlink. On community: showing up honestly and consistently in r/macapps and r/macOS — leading with the maker story and genuine help rather than spam — and letting others carry it through YouTuber reviews (free licenses) and a small, shareable free tool. The throughline is channels that keep working when I'm not personally posting.Developers often have deeply entrenched habits for managing their caches and build folders. How does Freshist's approach to safely surfacing these hidden gigabytes (like Xcode DerivedData and Docker caches) change their day-to-day workflow?Today most developers either forget these caches or clear them with risky, half-remembered rm -rf incantations. Freshist surfaces Xcode DerivedData, iOS device-support files, Docker, and npm/pnpm/Gradle/CocoaPods/Homebrew caches as named, sized categories — hardlink-aware, so the numbers are honest — and lets you review before anything moves to the Trash, with nothing risky pre-selected. It turns an occasional, nervous chore into a one-glance habit: open it, see the tens of gigabytes hiding in build artifacts, clear what you don't need, done in a minute. The shift is from "I should clean this someday, carefully" to "cleaned, safely, just now."Meet our sponsorsBright Data: Bright Data is the leading web data infrastructure company, empowering over 20,000 organizations with ethical, scalable access to real-time public web information. 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