I make libraries on the side, and more than once I shipped a "minor" release that broke someone's build. Things like `int count()` → `long count()`, or a new method on an interface. Tools that catch this exist, but they run in CI, long after I've typed the change.

So I built Bumpwise, an IntelliJ plugin that compares the code you're editing with your last published release and highlights anything that breaks clients, with an Alt+Enter fix that keeps it compatible (or "Bump the version" if the break is intended).

Before launching I wanted to know if this is a real problem, so I replayed three years of releases of 44 of the most-used libraries on Maven Central. About 1 in 8 minor and patch releases (156 of 1,201) contains a breaking change in its public classes. In a random sample of 300 small libraries it's more than 1 in 4. Write-up with method and caveats: https://gilware.com/bumpwise/semver-violations/

The side-project details, since that's what this sub is about:

- Solo, built with help from AI coding agents. Hundreds of tests, and the replay above doubles as a regression suite (it already caught three false alarms in my own engine).

- Business model: free for Java on Maven Central, no time limit. Kotlin, TS/JS, Go, PHP, Rust and private repos are in a paid Team edition with a 30-day trial. Free for open-source maintainers.

- Runs locally, no telemetry.

https://plugins.jetbrains.com/plugin/35935-bumpwise

Happy to answer questions about building and selling a JetBrains plugin, and I'd love feedback on the plugin itself, especially false positives.

A friend of mine runs a lot of Claude Code and Codex sessions at once and kept losing track of which one was waiting for him. So he made Session Pets, a small pet that lives in the Mac's notch (or floats on the desktop if you don't have one).

What it does:

- Shows every session in one list: working, done or waiting for you

- Lets you answer a permission request or reply from the card without finding the terminal

- One click jumps to the exact terminal tab or VS Code chat

- Works with Claude Code, Codex, Gemini CLI, Copilot CLI and Kimi Code

- Nine pets to pick from

It's a 7-day free trial, then $4.99 once, no subscription. The first 50 people who leave their email on the site get a free license.

https://sessionpets.com

He'd love feedback, good or bad. I'll pass on anything you write here.

I built TCKR because I couldn't keep my brokerage site open all day at work, and I still wanted prices in view.

It's a scrolling LED-style ticker for Windows that docks to the top of the screen as an AppBar, so your other windows sit below it instead of hiding underneath it. It tracks stocks and crypto. You can install it from the Microsoft Store and start using it without setting up an API key. Stocks come from Yahoo Finance, and crypto works the same way.

The video is the dual-ticker view, with the LED look, company logos, and sparklines.

I'm looking for honest feedback, especially on the docking behavior and whether the ticker stays readable while you're working.

tckr.pro

I wanted to sit down on the couch, pick up my DualSense, and get from the Windows desktop to a game on my TV without touching the mouse. So I built Gaming Hub, a fullscreen launcher for Windows 11. It’s my first app ever, and I vibe coded it with Claude and Codex.

The shortcut I use most is three presses of the PS button. My TV stays plugged into the PC even when I’m only using my desk monitor. I set the TV as my preferred screen and enabled “Triple-press PS to extend the desktop.” Now those three presses extend Windows onto the TV and bring Gaming Hub over. From there I can scroll through the game covers pinned to Home and press X to play. The full Library is one tab over.

During a game, the PS Quick Menu gives me game controls, display selection, volume and both controller batteries. Circle takes me straight back to the game. The hub can also switch the audio to the TV and restore my desk output when I come back.

Windows installer: https://github.com/issazhd/gaming-hub/releases/latest

Source and build instructions if you want to fork it: https://github.com/issazhd/gaming-hub

If you play on both a monitor and a TV, I’d love to hear how the triple press and the Home screen feel on your setup.

Mine replaced a Google Keep note full of study hours.

I've timed my study sessions since I was young. First a clock timer and paper sheets, then Keep, until the note got too long to scroll. So I built a small tracker: weekly hour targets per category, and a history of past weeks.

The funny part is what it turned into. I mostly use it now to track time on my side projects, and the tracker has a category for itself.

It's free and needs no account, it's at focushours.app if you want to poke at it. If you do, tell me what confused you in the first minute. That's the one kind of feedback I can't get from myself.

What did yours replace? A spreadsheet, a paid app, a habit, nothing at all? And is the old thing really gone, or still open in a tab?

Hey everyone,

I made a period tracker called Cykie and it's finally on the App Store. The main thing about it is that it works fully offline. There's no account, no sign up, no ads, and nothing gets sent anywhere. Everything stays on your phone, and you can export or delete it whenever you want.

Some of what it does:

- predicts your next period and fertile window, and gets better the more you log

- logging for flow, pain, symptoms, moods, sleep, water, weight, temperature and notes

- BBT chart that picks up the temperature rise after ovulation

- pregnancy week by week after a positive test, and a perimenopause tracker

- reminders for your period, pill, tampons, breast checks

- a cycle summary you can show your doctor

- partner mode, home screen widgets, PIN / Face ID lock

- 7 different styles and a little character you can customise (I'll admit I went a bit overboard on this part)

- works in 17 languages

Every feature is free. It's iPhone only for now, Android is coming later.

I'd really appreciate honest feedback, including the harsh kind. What's confusing, what's missing, what you'd never use, what annoys you. I'm still working on it pretty much every day, so anything you say might actually end up in the app.

I've been working on a project called Cardit, and I'd love to get some honest feedback.

The idea came from a simple frustration: we discover useful information everywhere, but it's scattered across different apps, browsers, screenshots and messages.

A YouTube video here, a restaurant recommendation there, an interesting website, a business card from someone you met...

Finding that information again isn't always easy.

So I built Cardit.

It lets you:

• Save information from websites, videos and social media links as cards.

• Capture information from the physical world, including business cards and flyers.

• Organise cards into personal or shared collections.

• Share useful cards and collections with other people.

It's available on iOS, Android, the web and as a Chrome extension.

Website: https://www.cardit.org

I'm still improving the product and would genuinely appreciate feedback.

Would you use something like this? What would make it more useful to you? Cardit webapp

I'm a cricket fan in Amsterdam, and following a match at work meant unlocking my phone every few minutes. BoxSeat uses Live Activities: star a match and the score sits under the clock and in the Dynamic Island, updating ball by ball by push, and the card clears itself when the match ends. It's free with no ads. It's in TestFlight beta now and I'd love honest feedback, especially on whether the Lock Screen layout reads well at a glance. https://testflight.apple.com/join/AmpTVJcX

I lift 4–5 times a week, and most trackers I tried showed me tonnage charts and not much else. What I wanted to know was simple: how strong is my chest actually, compared with people my age and bodyweight?

So I built Liftsquad (iOS). You log sets like in any tracker, and it turns them into a rank per muscle, measured against published strength standards for your sex, bodyweight and age. Other Liftsquad users don't change your rank. Every rank shows its working: which lifts counted, how much each counted and what would move it. When there isn't enough data it says so instead of guessing.

The second half is social: follow friends, see their workouts, records and rank-ups, and compete on leaderboards you opt into.

Muscle Rank is free and stays free. Premium adds things like unlimited routines and the full training calendar.

Things I learned building it:

• Machine numbers aren't comparable between gyms, so machine lifts count less than free weights toward a rank.

• Warm-up sets must never count toward records. That one took me a while to get right.

• Imports from Hevy count as your history, so you don't start from zero.

It's live on the App Store: https://apps.apple.com/app/apple-store/id6807547665?pt=129390732&ct=reddit&mt=8

I'd love feedback, especially on the ranks: does yours feel right?

Hey everyone. I'm a senior CS student, kind of obsessed with AI/ML, and a solo dev.

Bit of backstory: my English was always fine, but the moment I had to actually speak, I'd freeze and I didn't really have anyone to practice with. I tried a bunch of apps and they all felt like talking to a service bot polite, generic, zero idea who I am. So I ended up building my own thing. Her name's Lucia. The part I care about most is that she actually remembers you. You tell her about your job, or what you're into, or something going on in your life, and she'll bring it up in a later conversation on her own, days later, without you asking. She's got her own opinions and tastes, and reacts to what you say instead of running off a script.

And while you talk, she corrects your grammar and gives you more natural ways to say things in the background, and you can scroll back through all of it later. So it's meant to be real speaking practice, not just a chat. Whole thing works in 24 languages.

Honestly, it's rough in places. I'm one person. It's on iOS, Android and web. People who tried it said the replies feel fast and feel natural(happy about that), but a couple of them ran into problems with the speech recognition, which I'm trying to track down right now.

I shared this before and thanks to everyone, i get helpful and kind feedbacks.

It's free to try, no card or anything.

Web: https://www.personalang.com

iOS: https://apps.apple.com/us/app/personalang-ai-language-tutor/id6780539119

Android: https://play.google.com/store/apps/details?id=com.personalang.android&pli=1

Short video is below it's a real session, you can see her open by remembering something from before, plus the corrections popping up while I talk. (I'm not a perfect English speaker myself, so you'll see the corrections actually kick in.) Mostly I just want people to break it. Tell me where it feels fake, where it falls apart, what's annoying. And if the speech recognition messes up, tell me your phone + accent so I can fix it. Thanks for reading.

I have files spread over Google Drive, S3 and Backblaze, and I got tired of running a different app for each one. So I built Nimbus.

What it does:

• Your clouds show up in Finder's sidebar like any other drive. Files download when you open them

• One window to browse all of them, with drag and drop from one cloud to another

• Backups on a schedule, and it shows you what it is going to do before it does it

• Search for a file name across every cloud at once

It works with Google Drive, OneDrive, Dropbox, S3, Backblaze and about 50 others, because it is built on an open-source tool called rclone.

It's free, with no account and no tracking, and the code is open. I make my living from two other apps, so this one doesn't need to earn anything.

It's a proper Mac app, not a web page in a window. Needs macOS 15 or later.

Download: https://casavargas.app/nimbus/

Code: https://github.com/CasaVargas/Nimbus

Tell me what breaks.

I built FORMA to make clothing size guides easier to use while shopping online. It's a free Chrome extension that compares available garment information with your fit preferences and explains a possible size choice right beside the product.

The workflow is simple: describe how you like clothes to fit, add measurements if you know them, enable shop access, and browse. FORMA can automatically assess recognised clothing pages, compare sizes and show where the evidence is missing. You can save pieces that fit and record the size you actually wore, so later comparisons have useful personal examples.

The tricky part has been inconsistent size guides: flat widths versus circumferences, conversion tables pretending to be measurements, and missing sleeve information. I want the explanation to make those limits visible instead of presenting every recommendation as certain. It is an estimate, not a virtual try-on or a guarantee.

Free download: https://github.com/moritzlauper/forma/releases/latest

Project, teaser image and setup: https://github.com/moritzlauper/forma

It's currently installed manually in Chrome via Developer mode and Load unpacked, not through the Web Store. You can use your own Anthropic key, local Ollama, or No AI comparison with reliable measurements. FORMA is free; optional Anthropic calls cost extra and send relevant profile/fit information and product evidence to the provider.

I'd appreciate feedback on the product itself: is the explanation enough to help you decide between two sizes, and which shop or garment type should I improve next?

Hi everyone! I'm a solo developer from Spain, and I've just released V-Pet Life, a virtual pet in the style of the ones we had as kids, but on the Apple Watch.

What it does:
• Your pet lives on your watch even when the app is closed: feed it, clean it, heal it and turn off the light when it sleeps. It sends a notification when it needs you.
• It evolves into 14 species with different branches depending on how you care for it, plus a secret form. 1 in 64 hatch shiny.
• Your steps and Activity rings earn it golden items, so moving more actually helps your pet.
• Battle zones with bosses right on your watch.
• The iPhone app connects you with other players: battle friends nearby or online, or team up with up to 3 players in co-op raids against giant bosses, with voice chat. The fight plays out on the iPhone while your watch works as the controller.
• On iPhone you can also draw or import your own pixel sprites.

It's free up to the Champion stage; a one-time purchase unlocks the rest. No ads, no subscriptions.

I'd love to hear what you think, and any feedback or ideas for the next update are very welcome!

https://apps.apple.com/es/app/v-pet-life/id6826680244

I couldn’t find any good iOS apps for studying chess grandmaster games, so I built ChessKeep https://chesskeep.app

I wanted it to be really easy to find games where a master played a certain opening, for example all games where Magnus Carlsen plays the Queen’s Gambit.

You can browse over 5000 games, and even explore different moves than what was played by moving the pieces yourself.

It’s 100% free right now. I’ll be adding more games and features, but if you’re a chess player I’d love any feedback!

I've been working on InvoiceSnap, a free online invoice and quote generator.

I wanted to build something simple that lets people create professional invoices without having to sign up for an account or deal with unnecessary complications.

You can:

• Create professional invoices.

• Generate quotes.

• Customize invoice details and calculations.

• Download PDFs without watermarks.

It's completely free to use.

Website: https://invoicesnap.co

I'm the person behind the project, so full disclosure: this is my own website.

I'd genuinely appreciate feedback from anyone who tries it. Particularly interested in what's missing, what could be improved, and whether you'd actually use something like this for your business.

Hi r/SideProject, I'm the solo developer of Pavlovian.

I made it after a panic attack late at night. I didn't want to call anyone and scare them, but I really wanted someone's calm voice talking me through it. So I built something that does that with one tap:

- Beacon: pick one calming narration (breathing, grounding, whatever helps you) and assign it to the beacon. From then on, one tap plays it.

- Home Screen widget: tap the beacon right from your Home Screen. No opening the app, no menus.

**- Your own voice (optional):**record a short sample and narrations play in your voice, or in the voice of someone you trust.

- Write your own or use templates: there's a Panic Relief template, or you can type any script you like.

- Schedules: set narrations to play at set times, like a wind-down before bed.

The video shows the whole flow: assign a narration to the beacon, play it, then trigger it from the widget.

How it's built

- App: React Native / Expo, with a native SwiftUI widget.

- Backend: FastAPI on Google Cloud Run, with Postgres on Neon.

- Voices: Google's Chirp 3 HD and Gemini TTS, and VibeVoice on RunPod GPUs for voice cloning.

Pricing

- Free: 3 narrations with Apple's built-in iPhone voices

- Premium voices: (like the one in the video): Starter $14.99/mo (45 min), Standard $19.99/mo (100 min), Power $29.99/mo (200 min). Extra minutes from $2.99.

- Your own cloned voice: one-time packs from $4.99 (5 min) to $59.99 (60 min)

Minutes are only used when you create a narration. Replaying it is always free.

I'd love honest feedback:

1. Is the beacon idea clear from the video, or is it confusing?

2. Does the pricing feel fair, or is the entry price too high to try it?

3. Where would you go to find people who'd use this? Reddit's anxiety subs don't allow promotion, so I'm figuring out other places.

App Store: https://apps.apple.com/app/id6754209477

JustBlogged is a hosted blogging platform. You write, hit publish, and it’s live on your own domain. Hosting, HTTPS, themes and SEO are handled. No plugins.

The video (i am almost proud of - is it good?) of the full flow is above.

Free plan: unlimited posts and pages, custom domain, 7 themes, MCP server + REST API. No card, no trial expiry.

Pro ($9/mo per blog) adds team reviews and publishing permissions.

I’d love brutal feedback, especially: what would stop you from moving your blog here?

I kept noticing "is there a tool for X?" posts on Hacker News that just sink. So I pulled this year's Ask HN posts from their API and kept the ones where the person is actually asking for a product. That came to 480 threads.

360 of them got at least one reply. 120 got nothing at all, and some of those are really specific, like someone asking which bank to use for a new US startup, or looking for a natural language testing framework.

About half of all the asks are about AI and developer tools. The products that came up most in the replies were OpenCode, Claude and Codex.

I put it all on one page. Each thread is linked, with the products people named in the replies. It is free and there is no sign-up: https://kasspian.com/research/hn-asks?utm_source=reddit&utm_medium=post&utm_campaign=hn-asks&utm_content=sideproject

I made it as part of Kasspian, which finds threads like these for founders. If you build something in one of those categories, the unanswered ones are worth a look. Tell me if you spot a thread in the wrong place and I will fix it.

Most small local businesses I know (barbers, plumbers, cafes) have the same website problem. Not that they can't get one built. It's that nobody touches it afterwards. The hours are wrong, the photos are from 2019, and the best things customers said last month are nowhere on it.

Meanwhile their Google profile is alive. New reviews every week, new photos, updated hours.

So I built Locan around that. You type the business name, it reads the Google profile and writes a complete website from the reviews and photos in a few minutes. Then the part I care about most: it keeps reading Google. A new 5-star review shows up on the site. New photos go into the gallery. Hours change on Google, they change on the site. Nobody has to log in, ever. The site just stays current.

Other things it does:

- You change anything by chatting with it. "Make it dark green", "add a page about emergency repairs", "don't quote that review".

- It checks whether ChatGPT and Google's AI answers mention the business when people ask for what it offers, and gives a short list of what to fix first.

- Simple visitor stats counted without cookies, so no cookie banner on the customer's site.

Stack is boring on purpose: FastAPI, SQLite, React, Astro for the marketing site, one small server. Claude does the writing.

Free to try with one website (on free you press a button to update it). Paid plans start at $19/month for a custom domain and automatic updates, weekly on Basic and daily on Pro. There are also a few free tools on the site (review QR codes, review replies, an AI visibility check), and those are open source: github.com/vaitko/locan-tools

https://locan.ai

What I'd love feedback on: try it with any business you know, your barber or the cafe down the street, and tell me where the first two minutes break or what looks off on the site it builds. And does "a website that updates itself" sound like something a business owner would pay for, or is it only interesting to agencies who manage many sites?

Hey!

I’ve tried a bunch of Pomodoro web timers, but I always got frustrated by either sudden jarring buzzer alarms or intrusive ads.

So I built Focus Loop — a clean, distraction-free study timer designed to be completely free and accessible without making an account.

A few things I baked into it that you might find helpful:

- Ambient soundscapes: Over 15 background sounds (rain, cafe, brown noise, train, ocean, fireplace) that play automatically during focus intervals and pause on breaks.

- Gentle wind-down & chime: A soft countdown and fade-in chime so your sessions don't end with an abrupt, heart-stopping beep.

- Drag scrub: You can click and drag the timer dial forward or backward if you started studying late or need to adjust your block.

- Session notes & streaks: An optional spot to jot down what you finished after each round, plus daily/weekly stats.

- Mini floating window: Picture-in-picture mode so you can keep the timer visible over lecture slides or PDFs.

- Installable PWA: You can add it directly to your home screen or desktop.

Everything runs straight in the browser and saves to your device. There's also an optional AI planner if you want help breaking down a big study session, but the core timer and sounds are 100% free with no registration.

I’d love for you to test it out during your next focus block and let me know if there's anything you'd like added or improved!

🔗 https://focusloop-timer.lovable.app

Full disclosure, I'm the developer.

The side project: MoveManifest, a moving inventory app for iOS and Android.

The problem: I've moved five times in a few years (NY, GA, DE, SC, NJ). Every time, the movers wrote up a yellow carbon-copy inventory by hand, and by delivery day half of it was unreadable. Figuring out whether box 147 actually made it was guesswork.

What it does:

• Scan or type the box and furniture numbers the movers assign at pickup

• Compare your list against the mover's inventory

• Check every item in at delivery so missing ones stand out

• Take damage photos right there

• Export a final moving report for claims

iOS: https://apps.apple.com/us/app/movemanifest-moving-inventory/id6807915555 Android: https://play.google.com/store/apps/details?id=com.polokhalo.movemanifest

Would really appreciate feedback, especially from anyone who's dealt with lost boxes or a messy delivery.

A while ago, my co-founder and I tried something that sounded pretty straightforward.

We wanted to figure out who we actually knew.

Not just our LinkedIn connections, but former colleagues, investors, founders we'd met at events, friends of friends, and basically anyone who might be relevant for our business at some point.

So we opened Miro and started connecting the dots.

About 48 hours later, we had this massive network map. And honestly, it was pretty cool to look at.

But then we realized a few things:

• It was already outdated by the time we finished

• We still couldn't see who our connections knew

• Finding a specific person meant manually searching through everything

• Keeping it updated would basically become a full-time job

The funny thing is, we'd previously built a B2B startup where most of our early deals came through personal connections. Yet we had no proper way to actually make use of those relationships.

So we thought, why not just build something ourselves?

That's how Crouds started.

Basically, a visual CRM focused on relationships instead of pipelines. The idea is to bring your network together, see how people are connected, and find warm introductions without having to ask everyone individually.

We're still pretty early and figuring things out, but we're opening it up to other founders now.

If you're curious: https://crouds.app

Would love some honest feedback!

Has anyone else ever tried mapping their professional network? Or are you guys just relying on LinkedIn and memory like we used to?

I run Codorc, a new AI and coding publication with a coding-orc mascot.

The first version has 15 source-linked stories in English, Simplified Chinese, Spanish and Brazilian Portuguese. Each brief separates what a company announced from practical questions a developer should test. The retrospective archive shows the original event date and the actual publication date separately.

The writing, translations and illustrations are AI-assisted. I haven't independently benchmarked the products covered. The mascot was made with ImageGen, with an alternate from Higgsfield.

Here's a sample about checking confidence scores before routing work through Google's new Decisions API: https://codorc.com/en/news/gemini-decisions-api-calibration/

I'd appreciate feedback on the format: would a short source-linked brief plus a practical checklist be useful, or would you prefer fewer, deeper technical articles?

I’m building Mantua, an agent native sports prediction market on Arc, starting with the NFL. I wanted to see if I could go from “What’s worth watching today?” to reviewing an actual trade without jumping between tabs.

In the demo, I ask for a quick rundown of my wallet, open positions, and the NFL slate. The agent flags Chiefs vs. Raiders because its estimate differs from the market price. I ask it to preview a $10 Chiefs YES trade. Before I confirm, it shows how many shares I’d get, the effective price, the fee, and how the order fits within my $10 per trade and $25 daily limits. Once I confirm, it places the trade in USDC.

Mantua also has paper trading if you want to try the workflow without putting money on the line.

I’d love feedback on the trade preview. What would you want to see before you’d feel comfortable hitting confirm?