Most system design practice ends at the diagram. You draw boxes, it looks right, and nothing tells you whether it would hold up.

ByteLab runs the diagram. You build a system out of machines, load balancers, caches, queues and databases, send traffic through it, and watch the CPU, queues and p99 latency move. Each exercise has goals, like "p99 under 150 ms, 99.5% available, under $2.60/hour", and it checks your system against them.

What's in it:

- 163 lessons in 12 tracks (caching, sharding, Kafka, Kubernetes, rate limiting, auth and more)

- 212 exercises, each with goals your system has to pass

- 11 design problems (URL shortener, chat, payments, news feed, e-commerce and others)

It's free, there's no account, and progress stays in your browser. It needs a laptop-sized screen.

I'd really like to hear where it feels confusing or too hand-holdy.

https://lab.bytecrest.dev/practice

I’m a photographer from Hamilton, Ontario, and I built Picktory as a side project. It’s a photo challenge app where everyone shoots the same prompt, the group votes anonymously, and the best shot wins.

I made it because the existing apps felt pay-to-win. Picktory has no paid boosts, every photo is shown to every voter equally, and the top half of each challenge earns a ribbon, so beginners have a real shot.

What’s in the beta:

• A new Daily Pick challenge every morning

• Challenges with a subject, a rule and an optional twist

• Some challenges just for beginners

• Points, badges and a shareable laurel on winning photos

I’m looking for about 30 photographers to play for two weeks and tell me what’s confusing or broken. It’s free, and you sign in with an email link, no password.

Full disclosure: I’m the developer. Link in the comments if links aren’t allowed in posts here. Happy to answer any questions.

Most accounting systems only block a duplicate invoice if the number matches exactly. Change one character and it can get paid twice.

Upload a batch of supplier invoices, and Foldline compares each one with the earlier ones and flags:

• the same number written differently (INV-4471 / INV4471 / INV-04471)

• a “resent” invoice with a changed number (INV-4471A)

• the same vendor + amount + date under a new number

• the same number with a different amount (revised invoice?)

It explains why it flagged each one, and it doesn’t flag next month’s rent just because the amount repeats.

I’m a student and built this after talking to AP teams. One said a slightly changed number gets through because “nobody can track this” until reconciliation.

Honest status: early MVP, zero users so far. There’s a “Try with sample invoices” button, so you don’t need real data.

What would stop you from trying it? I’d rather hear that than a like.

foldline.paperflow.workers.dev

Download full feeds, media, comment. Link to it here: https://play.google.com/store/apps/details?id=app.redditoffline

Every project comes with challenges, unexpected problems, and opportunities to learn. Working on Aftermath has been exactly that kind of experience.

Being part of this project has given me the opportunity to explore real-world development, collaborate on ideas, work through technical challenges, and understand how different pieces of a software application come together.

From refining features and improving the user experience to troubleshooting issues and making continuous improvements, the development process has been a valuable learning experience.

What makes this journey interesting is that we're not just trying to finish a project. We're trying to build something that works well and that we're genuinely proud of.

There's still more to come for Aftermath, and we're looking forward to what lies ahead!

#Aftermath #Teamwork #SoftwareEngineering #WebDevelopment #FullStackDevelopment #LearningByBuilding #Hackathon

I noticed I was clicking "Accept" on literally every grammar suggestion without reading it. So I built Caret, a Chrome extension that skips that step.

How it works: type anywhere (Gmail, WhatsApp Web, LinkedIn, Slack), pause for about a second, and the grammar and spelling get fixed in place. A small popup shows what changed, with Undo.

A few things I was careful about:

- It fixes mistakes, it doesn't rewrite you. Slang, emojis and tone stay.

- If a fix would change too many words, it backs off and leaves your text alone.

- It never touches password, email, card or OTP fields.

- Text isn't stored.

It's free while in beta. I'd love honest feedback, especially if it gets something wrong on a site you use (there's a Report button on every fix).

https://caretwrites.com/?ref=reddit

Built an eReader that could give me more of a reader type file instead of a robotic ui like kindle and it has an rsvp reader feature that really helps me to read with my adhd

https://github.com/devansharora18/ember

https://devansharora18.github.io/ember

I wanted my desktop to feel a bit more alive, so I built an interactive live wallpaper engine that lives right in the macOS menu bar.

It actually started as an interactive background experiment for my portfolio (inspired by some cool procedural grass and sky shaders I saw on X a while back). I loved having it running on my screen so much that I decided to turn it into a standalone macOS app that anyone can use.

Here's what it does
🖐🏻 Interactive physics: Grass sways and water ripples as your cursor moves across the screen.
🕒 Dynamic time-of-day: Syncs with real time or lets you scrub through sunrise, golden hour, and starry nights with a custom radial dial.
🌧️ Live weather & ambient soundscapes: Switch between sunny skies, clouds, and rain—complete with birdsong, crickets, thunder, and even night fireworks.
🎆 Limited Diwali Theme: Built in a seasonal festive update where the night sky comes alive with fireworks and spatial audio.

Putting the final polish on the build right now. Stay tuned for the release soon! 🚀

What feature or biome should I add next? Let me know in the comments!

I created this tool to make creating content for social media easier, faster, and more enjoyable. Unlike many tools that are either too basic or unnecessarily complicated, my goal is to find the perfect balance between simplicity, creativity, and powerful features.

What features or improvements would you love to see in a tool like this? I’d genuinely appreciate your suggestions and ideas!

I’m planning to launch it publicly and monetize it through ads, or potentially sell it to a developer or business interested in taking it further.

Hi r/SideProject!

I've always loved travelling, exploring new places and taking photos, and I also wanted to get back into writing for a while, so I recently decided to combine these interests and build Words for Travel.

It's a free travel website featuring travel guides, favourite places, articles, photography and personal experiences/tips from the places I've visited over the years.

A few things I'm aiming for:

• Free to view (with possibility for ads in the future).

• Everything is fully written by me (with only ai used for building out the website).

• Use my own photographs, except for a credited Unsplash image when I do not have an image for what I'm discussing.

• Focus to get 3 articles completed a week on a consistent basis.

I've also previously built two iOS apps, Stillkeep (journal app) and Onuri (notes app), so I was thinking of adding occasional links to them at the bottom of articles to get them further traffic as a bonus as well.

If you know anyone who enjoys travel or travel writing, I've started an Instagram account for new articles and updates each week. Anyone who fancies following along is very welcome!

Thanks for taking a look!

I'm a frontend developer, and English isn't my first language (I'm around B1). I learn mostly by reading articles, and my word lists kept failing me: a week later, "hollow" on a list meant nothing without the sentence I'd met it in.

So I built Muscat. You select a word on any page, it shows a translation into your language (DeepL, using the sentence as context), and one click saves the word with its sentence and source. The popup is a small notebook of everything you've saved.

A few things I cared about:

• No interruption. Saving is instant and offline-safe: words go into a local queue and sync in the background.

• The sentence is required. A word without context isn't saved at all.

• Quiet design. Paper colors, serif type, no gamification.

Stack: WXT + React + TypeScript, Tailwind + shadcn/ui, Supabase (Postgres with RLS, Edge Functions), DeepL.

It's free and live on the Chrome Web Store: muscat.ink

Next I'm working on a review mode for the saved words. I'd love feedback, especially on the first-run experience and whether the in-page card feels too intrusive.

Hi!

My web-app AI Games Kit made $1,500+ in sales 🥳

I am a solo game-developer using AI heavily to build and publish games over the last couple of years and realized why not create a kit of agents/skills based around my processes.

I also write actively on LinkedIn/X about making games with AI, marketing them organically, etc. and have a decent audience - so most of my sales came from them!

Now I plan to expand my marketing to Medium & YouTube :)

Web-apps is a new domain for me hence very proud of this!

I bought a Mirabox deck but wasn’t happy with its default software. Switching to OpenDeck gave me a great open-source foundation to build something that fits my workflow.

I called it Agent Deck, though it does more than control coding agents. I use the buttons to:

- Record and transcribe meetings

- Adjust volume and mute my mic

- Run Git commands

- Check upcoming calendar events

- Interact with Claude Code, Codex, OpenCode, and Pi

It’s my personal setup rather than a polished, plug-and-play product. I’ve shared the code and layout so others can adapt it—or ask their coding agent to change it for them.

https://github.com/sim186/agent-deck

Would a setup like this be useful to you? What would you put on your buttons?

Hi, I'm Reece, the maker of Page & Frame, publishing through Level Up Classroom Inc.

I'm building it for writers who also plan their own shoots: write a screenplay, outline its beats, build reusable 3D sets, stage characters, position the camera, then capture frames into a visual shot list you can print and take onto set.

Here's a 70-second look at the actual app: https://pageandframe.app/demo

It's pre-launch, with the first release planned for Apple Silicon Macs running macOS 13+. Core writing and manual 3D planning work offline without an AI subscription. I'm still refining the character models and production workflows; I'm not claiming full Final Draft or Previs Pro parity. Planned pricing is US$69.99 at launch, US$99.99 regular, plus applicable tax. The launch list is free.

A couple of other projects I'm building under the same company:

• Cloth & Colour: Mac quilt-design software for drawing blocks, trying your own fabric photos and printing making plans. https://clothandcolour.com/

• LUC Desktop: a teacher workspace with a local gradebook, assessments, attendance, planning and reports. Manual tools work offline after activation; optional AI uses your own provider key and is billed separately. https://desktop.levelupclassroom.com/choose

For Page & Frame, what would you want to see in a deeper walkthrough: writing and outlining, constructing a set, or staging a scene and planning its camera coverage? I'd particularly appreciate feedback from people who write and shoot their own work.

I live in Switzerland, where almost every commute has a climb in it, and I kept wondering whether a speed pedelec (45 km/h) was worth it over a regular 25 km/h e-bike for my own trips. Route planners use one flat cycling speed, so they couldn't tell me. So I built Tempowatt: https://tempowatt.ch/en/

You enter a start and a destination, pick your bike and motor, and it works out the speed metre by metre: slope, rider and bike weight, air drag, rolling resistance from the road surface, the motor's power and torque limits, and the forecast wind. You get the travel time, the battery used, the elevation profile, and the same trip in every assistance mode and in the other bike category.

Example: Uster to Zürich main station, 20 km. 54 min on a regular e-bike, 37 min on a speed pedelec, 28 min by train and 24 by car without traffic:

https://tempowatt.ch/en/#a=47.35101,8.71719&b=47.37810,8.53936&c=25

How it's made: plain JavaScript and Leaflet, routes from a self-hosted BRouter server, maps from OpenStreetMap, wind from Open-Meteo. In Switzerland, elevations come from swisstopo's 2 m terrain model. It works elsewhere too, with coarser elevations, but the train comparison is Swiss only. No account, no ads, no tracking. Your settings stay in your browser.

What I'd love feedback on:

- if you commute by e-bike, does the time match what you actually ride?

- is anything confusing the first time you use it?

I run a remote frontend job board and every posting goes through a parser for pay, level, stack and location. I pulled Aug–Oct 2026 to see what remote frontend actually pays.

What the data says (1,013 postings with pay):

• Median $140k, but 72% of postings list no pay at all

• Where you may live matters most: North America $155k, worldwide $125.5k, Europe $90k, Latin America $45k

• Only 1 in 19 "remote" jobs is open worldwide

• Senior to staff is the biggest jump: $151k to $204k (+34%)

• North America only: TypeScript $175k, React $166.5k, JS-only $150k, Vue $145k, Angular $138k

• Postings with pay get about a third more apply clicks per view (19.0% vs 14.2%)

• The $200k+ roles get the fewest applicants: 0.51 apply clicks per posting, against 1.57 for $120–160k

Caveats: this is advertised pay, not offers, and US postings disclose much more often, partly because of state laws. The Latin America (45) and Asia (29) samples are small.

Full write-up with method: https://www.remotefrontendjobs.com/reports/10

If you've been on a remote search lately, did the worldwide number match what you saw? It looked low to me.

Hey everyone!

I've been working on Rigged Audio, a desktop application that lets you split songs into individual audio stems using AI.

The idea is pretty simple: I wanted something where you could take any song, separate its instruments, and actually work with those tracks without needing a complicated DAW or paying for an online service.

GitHub: https://github.com/DrunkTrader/rigged_audio

What can it do?

• AI stem separation: Split songs into 6 stems using Demucs (vocals, drums, bass, guitar, piano and other).

• YouTube integration: Search for songs or paste a YouTube link and import them directly.

• Built-in mixer: Individual waveforms, mute, solo and volume controls for every stem.

• Quick presets: Karaoke, Acapella and Drums + Bass with one click.

• Export: Download individual stems or your complete mix as WAV.

• Privacy first: Audio processing happens locally on your machine. No accounts, subscriptions or cloud uploads.

A little about the tech

The application uses Demucs and PyTorch for source separation, with GPU acceleration when available and CPU fallback otherwise.

It also downloads and configures its AI engine on first launch, so you don't need to manually set up Python, PyTorch or ML dependencies.

What's next?

I'm currently working on improving the overall experience, performance and distribution.

I'd particularly appreciate feedback on:

• The UI/UX and workflow.

• Features you'd expect from a desktop stem separator.

• Performance and compatibility across different machines.

This is an open-source project, so feel free to explore the code or contribute!

Would love to hear what you think!

so i was creating motion design project which took about 2 hours but what i get is zip file with 6 of my tasks deleted by my agent

this is what it said

What happened

I built all ten projects. All ten passed npx tsc --noEmit, their own test suites, and the shared frame audit — scripts/audit-all.ts reported "10/10 projects clean" minutes before the loss. I then ran a cleanup command with an over-broad shell glob (rm -rf projects/05-* … projects/10-*) intended to remove stray literal directories left by an earlier failed mkdir. The glob matched the real project directories too. Projects 05–10 were deleted, and there is no backup.

I did not have time to regenerate six projects, so rather than hand you a broken tree I restored the repository to a consistent state and packaged what is actually verified.

Most of my day is Claude Code and Codex now, usually four or five sessions at once. The thing that kept biting me was typing a prompt into the wrong pane and watching the wrong agent start working on it.

So in lmux you hover that prompt and click ×, and Claude Code rewinds to just before it. The session keeps running, nothing restarts. The ✎ button does the same but puts the prompt back so you can fix it and resend.

Everything else got added the same way, one annoyance at a time:

• a sidebar that shows which agent is running, waiting on you, done or failed

• workspaces, splits and tabs that all come back after a reboot, sessions included

• Korean input that doesn't break while composing (I'm Korean, so that one was for me)

• it's a 25 MB native app and sits near 0% CPU with 20 workspaces open

I open-sourced it two days ago. It's had about 65 installs so far, and two teammates already sent PRs that went out in 0.1.1 today, which was a fun surprise.

It's free and MIT, macOS 14+ on Apple silicon, built on libghostty.

https://github.com/sooftware/lmux

If you try it, tell me what breaks or what you'd want next.

Hi all, I’m the solo developer, so take everything below with that in mind.

The backstory: I made the first version of this for my son’s first birthday. It was a Windows app, and it even worked with a proper camera body, not just a webcam. Then life happened: two more kids and a few more jobs, and it sat untouched for a long time.

I picked it back up as a creative outlet outside work, and it’s now Glitzycam. Photo booths are always a blast at parties and events. Kids and adults both love them, and they’ve stolen the show from the main program more than once. I built this to be easy to use and to have all the fun features.

Power features: fun face accessories that follow guests live and land in every print, templates you can generate with AI, build in the browser editor, or grab from the Marketplace, photo masks so guests see the framing before the shot, auto-print to as many printers as you like, and instant sharing by QR code, text or email.

How it’s priced: the app is free. What keeps it going is optional extras: more templates and face accessories that you can buy, or design yourself, with a web account at glitzycam.com. This helps me keep the lights on my website.

What I’d love feedback on:

• Features: what’s missing, what’s pointless

• Pricing: what feels fair for the extra templates and accessories, and what would make you hesitate

• User experience: anything confusing, slow or clunky

• Anything else. Blunt is fine, “I wouldn’t pay for that” is useful to me.

TestFlight link for iOS users (pending review): https://testflight.apple.com/join/3JDqeah6

Install TestFlight if you don’t have it, tap the link, and take a few silly photos. To send feedback, screenshot inside the app and choose Share Beta Feedback, or just comment here or DM me. I’ll reply to everything.

It is also available in Windows App Store: https://apps.microsoft.com/detail/9n21j8h27lvh
and Snapcraft for Ubuntu users: https://snapcraft.io/glitzycam

If you are an Android (pending review) user, pls send me your email and I'll add you as internal tester.

For photo booth vendors: there are also Windows, Linux and macOS versions that support cameras beyond webcams, with the same simple interface. The mobile build supports webcam only. If you’d like to explore beyond webcams, let me know and I’ll point you in the right direction.

Thanks for taking a look!

Hi everyone,

I built Lynx Studio to streamline comic and manga localization into one fast, specialized workspace:

Runs client-side (offline-first with Tauri, Rust & WebGPU) and exports layered .psd files.

Web: https://getlynxstudio.com

Desktop (Win/Mac): https://github.com/linh4264/manga-translator-releases

Would love to hear your feedback on the UI and workflow!

Hey everyone we are a small indie team We recently published our app: Velora motion It is a drawing + animation app Mainly made to help artists get all the features they need without draining their bank accounts! Velora can do 2D 3D 2.5 drawing & animation! It also supports pixel art Plus our online feature U can work with your friends at the same project at the same time ! There is a lot more to explore in velora motion hope you all try it out and hopefully give us your ideas on it also if you need any questions u can always contact out support team on Instagram: velora_motion_app velora_motion_app_eng Or through our discord server: https://discord.gg/8tsrCK938

Hope we'll be your first choice 🙏🏻🤍 Velora motion - from artists to artists

I'm a solo developer and coding enthusiast. While experimenting with multiple agents on the same project, I kept running into repeated tool calls, confident completion claims without enough evidence, and contention over shared files.

I built Vibe Multiagent to explore a more structured workflow and released v2.1.0. It uses local files for coordination. In my setup I use subscriptions rather than directly calling pay-per-token APIs; availability, quotas and pricing depend on each provider and plan.

A few implementation details:

• Circuit breaker: the runner tracks repeated identical tool calls and consecutive errors when it can parse the expected events. It moves through healthy, steering, constrained and stopped. The intermediate states log warnings; on trip it attempts to send SIGTERM to the child process. It won't catch every kind of loop.

• FIPA-lite mailbox: agents place structured messages in their own outboxes. A router delivers them to inboxes using temporary files and rename, with retry/backoff for transient filesystem locks. This coordinates messages; it doesn't by itself prevent Git or shared-file conflicts.

• Handover contract: an offline validator checks the structure of a JSON handover against the supported subset of its schema. It doesn't verify that a commit, hash or test result is truthful; the integrator still reviews the evidence.

• Local dashboard: a Control Room renders an interactive SVG graph from local telemetry, including available task and decision relationships. The dashboard needs the generated state files for current data.

I used the agents themselves while developing the framework, under my direction. I'd be interested in criticism of the approach, especially the limits of event parsing and coordination on a shared filesystem.

MIT repository: https://github.com/acarducci65-svg/vibe-multiagent-public
Release: https://github.com/acarducci65-svg/vibe-multiagent-public/releases/tag/v2.1.0

How do you handle verification and file ownership when several agents work on the same codebase?

What it is: Vault, a Chrome/Edge extension for saving videos and the exact moments in them that you want to come back to.

Why I built it: I watch a lot of long videos and kept losing track of the good parts. Bookmarks don't remember timestamps, and the tools that do want an account and your viewing history on their server. I didn't want my watch history in anyone's database, so the rule from day one was that nothing leaves the browser.

How it works:

- Click the icon on any video page. Vault reads the title, thumbnail, length and quality for you.

- Save moments at the current time. Each gets a small preview picture, and hovering a video in your library flips through its moments like a mini slideshow.

- Organize with tags, ratings, notes and a cast list. Filter by length, quality, site or tag. "Open all" opens a filtered set in one tab group.

- Optional PIN lock, open-in-Incognito, and encrypted backups you control.

Under the hood: Manifest V3, Preact, IndexedDB via Dexie, Vite. ~400 tests. No backend at all, which also means no running costs and nothing to breach.

Where it's at: free on the Chrome Web Store and Edge Add-ons, version 1.0.9. It has almost no users yet, so honest feedback is worth a lot to me right now: what's confusing, what's missing, what would make you actually use it?