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danieldratschuk

6 karma · joined August 6, 2026

Math grad from Germany. Building Clef, an app for learning piano.

Before that I trained a transformer for optical music recognition (Transcoda, NeurIPS submission). I play piano myself, mostly Chopin and Liszt. Taught myself Japanese to JLPT N1, mainly with Anki and small tools I built for it, like a popup dictionary in C.

danieldratschuk.com daniel.dratschuk@gmail.com

submissionscomments
danieldratschuk··on Show HN: Clef – spaced repetition for piano over MIDI
Thanks! It's determined via the FSRS algorithm. It starts out with the average retention curve for flashcards, but then adjusts to you as it learns your patterns. In the future, as I have more data, the initial curve can be tuned for piano specifically (since muscle memory degrades differently than plain text).
danieldratschuk··on Show HN: Hope, 1-on-1 AI Tutor for kids Grades 2-10 learning math
Took another look to be specific. I think the information is actually all on the page, but it's never said in a plain sentence. The headline gives the outcome ("A grade ahead in math") and the sections give the feeling ("Never boring. Never impossible.", "A quiet starting point"), so I had to piece together the actual workflow myself from the Sketch / Show work on paper / Ask Hope cards. Something like "Hope gives your kid a problem, they work it out on paper or the sketchpad, Hope reads the work and nudges" never appears anywhere, even though after reading the whole page I believe that's what it is. Also the hero replay moves too fast to actually read the exchange, and that demo is the one thing that would show what Hope does.
danieldratschuk··on Show HN: Hope, 1-on-1 AI Tutor for kids Grades 2-10 learning math
The general idea seems decent, and "just slightly above your skill level" is a real learning technique. One thing I'd be careful with is hints. In math you need to struggle through a problem to really get it, and students tend to instantly look the hint up instead. Self-restraint doesn't work here, so I'd think about how the app gates them (couldn't tell how you handle this since I didn't sign up).

Some smaller notes on the landing page: it looks really good, but it feels very abstract, so it wasn't immediately clear to me what the product actually does. The hero demo would be the place that shows it, but it moves too fast to read. Also "Hope" sounds slightly depressing for a tutoring app, like "this is my last hope for better grades", haha. Good luck!

danieldratschuk··on Show HN: Vocab Top – AI-powered vocabulary builder that helps you retain words
I made a popup dictionary for myself when I was learning Japanese. The thing that made me actually use it was that it works on selected text in any app, one hotkey, right where I'm reading. Every time lookup meant switching to a browser and typing the word in, I stopped bothering after a few days. So I'd worry less about the entries themselves and more about how fast someone can get from "unknown word in front of me" to the definition.