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kebsup

625 karma · joined November 15, 2020

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kebsup··on Postgres isn't slow, your storage is
I was using postgres for embarrassingly long time before I've learned the difference between "index scans" and "index only scans".

Including relevant columns in the index can massively improve the performance, because postgres does not need to read the randomly sorted tuple in the original table.

kebsup··on Flutter 3.47
If anyone is interested to see the WASM + canvas renderer performance compared to Android/iOS builds, I've build my app for the web.

The web app is here: https://app.vocabuo.com (completely free) And the links for Android/iOS builds are here: https://vocabuo.com (soft paywall)

To an untrained eye who does not care about dropping a few frames, the web version is almost indistinguishable from the "native" build. Especially if you add it to homescreen from safari to hide the navigation bar.

kebsup··on Ask HN: What are you working on? (May 2026)
I'm working on a language learning app that combines spaced-repetition flashcards with a browser, ebook reader and a youtube viewer.

The main difference between my app and anki/other generic flashcard apps is that it is for vocabulary only, which allows me to add features specific for language learning.

For example, you can set it up such that each word shows up with a different sentence and image each time you see it.

https://vocabuo.com

kebsup··on Ask HN: What Are You Working On? (March 2026)
https://vocabuo.com - A spaced-repetition flashcards language learning app that allows you to extract words from websites, youtube and conversations with ai.
kebsup··on Ask HN: What are you working on? (February 2026)
https://vocabuo.com

Learn languages with spaced-repetition flashcards from content such as ebooks, websites and videos.

kebsup··on Ask HN: What Are You Working On? (December 2025)
I’m working on Vocabuo (https://vocabuo.com/), a vocabulary-focused language learning app.

Two main differences between this and other Anki-like apps: 1) The words you learn are from YT videos, websites and ebooks you import in the app. 2) The flashcards are optimized specifically for learning vocabulary - cards automatically get audio, images, multiple sentence examples, words definitions etc. It can also create fully monolingual flashcards with just definitions or the words in dialogs.

My biggest flex is that I have users who have done more swipes than me (over 100,000).

kebsup··on Ask HN: What are you working on? (September 2025)
What’s baseless about it? The yearly subscription price is like 20 minutes of work for programmers and many users are spending tens of hours on the app.
kebsup··on Ask HN: What are you working on? (September 2025)
I'm working on spaced-repetition language flashcards app, that shows you variety of card types (sentences, reverse, audio, definition...) and allows you to add vocabulary from content - youtube, ebooks, website reader.

ios: https://apps.apple.com/us/app/vocabulary-flashcards-vocabuo/... android: https://play.google.com/store/apps/details?id=world.petr.vok...

kebsup··on Show HN: I built FlipCards – a flashcard app with variations to improve learning
Nice to see someone taking the concept of card variations to all concepts.

I'm taking this to extreme with Vocabuo[1] for language learning. For a single word, I have cloze cards, reverse cloze, definition cards, dialogs, audio and a few more.

At some point, I'd like to take the card type into account when calculating the next repetition stage, but that's a bit far into the future.

[1] https://vocabuo.com

kebsup··on Content-Aware Spaced Repetition
Thank you for the report! I was thinking of redoing the landing page for a while anyway. Are you using a niche browser or something like that? I haven't had anyone experience this issue nor was I able to reproduce it.
kebsup··on Content-Aware Spaced Repetition
I'm building a SRS language learning app [1] so I've thought about this topic a bit, but I've come to a conclusion that srs algorithms might be just a nerd optimization obsession. My app has "stupid" 1,3,7,15,30 or something like that intervals, and the reality is that if I know a card, I can swipe it within 2 seconds, and if I just barely know it, I can spend 30 seconds on it.

So optimizing the algorithm such that every card comes at the exact right moment might cause all cards to feel too hard or too easy. I think having a mix of difficult and easy cards is actually a feature, not a bug.

[1] https://vocabuo.com

kebsup··on Show HN: SnapQL – Desktop app to query Postgres with AI
I was looking for something like this that supports graphs.
kebsup··on Ask HN: What are you working on? (May 2025)
https://vocabuo.com

App with dynamic/flexible spaced repetition flashcards for language learning.

Recently I've added dialog & definition cards, so I can learn German from short dialogs with images and audio.

kebsup··on Spaced repetition systems have gotten better
I've been looking into FSRS since I'm building a language learning app[1], but I haven't implemented it yet. Can FSRS work if I don't want to have 4 choices - bad, good, hard...? I have found myself to get into a decision paralysis so just bad/good works better for me. Plus I can swipe the cards tinder style! :D

My second reason is that I'm worried about the complexity - both from non-nerdy users perspective and me having to debug it.

[1] https://vocabuo.com

kebsup··on Ask HN: What are you working on? (March 2025)
I’m building a spaced-repetition flashcards app. Unlike the competitors, the cards have audio, images and sentences. Additionally, it is possible to add words from ebooks, websites and YouTube.

https://vocabuo.com

kebsup··on The average college student today
I've finished my Bc. in computer science before AI, but even then, sitting through a 1.5h long lecture and reading a textbook was just not the way to learn.

a) better quality lectures were available online - it's much easier to learn linear algebra from top MIT Professor than a random one at my university

b) the text books were absolutely terrible compared to what was available online

I can understand that 20 years ago people were captivated with the physical lectures because it was the only way. Today however, professors are competing with 3blue1brown, Khan academy, pre recorded lectures from top universities and many more great resources. Standing in front of a blackboard slowly going through an unintuitive math proof is just not going to cut it and people will get bored.

kebsup··on Ask HN: What are you working on? (February 2025)
I'm working on an AI spaced-repetition flashcards app for learning vocabulary in foreign languages.

https://vocabuo.com

The idea is to have srs flashcards, like Anki, but without the pain of creating example sentences, translations, images and audio.

As a bonus, I've added the option to add vocabulary from ebooks, YouTube videos and websites.

kebsup··on One year after switching from Java to Go
I'd consider a lot of spring annotations "black magic" , because you can't simply go to definition and see how/what they do.
kebsup··on XAI told me I either had to delete the post, or face being fired
Seems to me that he thinks he's being fired for mentioning that grok 3 exists but he's actually being fired for saying that chatgpt is better than grok 3.
kebsup··on Recent results show that LLMs struggle with compositional tasks
I've managed to get llms fail on simple questions, that require thinking graphically - 2D or 3D.

An example would be: you have a NxM grid. How many shapes of XYZ shape can you fit on it?

However, thinking of the transformer video games, AI can be trained to have a good representation of 2D/3D worlds. I wonder how it can be combined so that this graphical representation is used to compute text output.

kebsup··on Show HN: Personalized Duolingo (kind of) for vocabulary building
Great app! I've been building something similar, but for less advanced language learners, who wouldn't understand definitions in their target language.

My app [1] is basically a combination of SRS flashcards with an ebook/YouTube/Website reader. Unlike Anki though, AI creates example sentences, definitions, images and audio.

I find it interesting that you want to get inspired by Duolingo. My approach is to have the most efficient grind possible - no gamification. I've found Duolingo was wasting so much of my time with exercises that did not really teach me anything and took a long time to complete + the XP points/levels etc. were quite distracting.

[1] https://vocabuo.com

kebsup··on TikTok Shutdown: Why building on proprietary platforms is a risky game
This is one of the reasons why I'm building my app in Flutter and not Swift/Android, which is not mentioned a lot in cross-platform vs. native discussions. Neither of the native frameworks compile to JS/we assembly, making it useless if the app gets randomly deleted from stores.
kebsup··on Show HN: I made a tiny game that helps increase IQ
Nice game! Not sure about the IQ though :D
kebsup··on How bloom filters made SQLite 10x faster
You don't go through entire loops everywhere because if there isn't a match in the first two tables, you don't have to check the match with the third table.

It's better to check A x C before A x B if you know that A x C has less matching rows, because the final loop will be shorter.

kebsup··on I Built a Figma Plugin That Generates Custom SVG Illustrations with AI
Are you saying you don't want to unlock your full creative potential with unique and scalable ai designs?!?
kebsup··on Ask HN: Those making $500/month on side projects in 2024 – Show and tell
Neither is.

Gifmemes - you can buy a 10 USD watermark removal Vocabuo - freemium and you can buy classic Appstore/Playstore subscription to unlock the other 80% of the features

kebsup··on Ask HN: Those making $500/month on side projects in 2024 – Show and tell
I have two!

https://gifmemes.io, haven't touched the code for years, makes between 100-300$ a month, depending on the season.

https://vocabuo.com - a side project I hope to turn into a business, so I work on it around two days a week, made around $3.5k in revenue last month but most of it went back into ads.

kebsup··on Ask HN: What Are You Working On? (October 2024)
A language learning app that combines Anki like spaced repetition with language learning ai tutor. https://vocabuo.com
kebsup··on FTC's rule banning fake online reviews goes into effect
While making an app, I'm learning what other people in the industry are doing. One piece of "advice" is to put AppStore/play store rating dialog in the onboarding. The case studies show that it indeed improves the reviews by a lot, because people simply rate 5 stars just to get through onboarding.
kebsup··on Learning to Learn
800 is definitely too little. I'm building a language learning app based around this exact strategy. Right now, I've around 7000 German lemmas tracked in the app and still regularly encounter sentences which I don't understand, because I lack the vocabulary.
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