Solo founder · builder · maker of too many things

Sora Kalden

I build apps and businesses, write worlds, run games, and learn hard things in 30-day sprints. Here are a few of mine — scroll through, and let's build the next one together.

the worlds
Flua — real app screenshots
01 Building

Flua

The fastest honest path to a new language — one expertly-ordered deck, real native audio, spaced repetition that does the thinking for you. I taught myself Japanese to A1 in ~20 focused hours with this method, then spent a year building the app that strips out every ounce of the friction that makes people quit.

Kōyasan in autumn
02 Worlds & stories

I've been building worlds since I was 11.

It started with a fantasy world I dreamt up as a kid and faked my way into publishing as a novel at 14. The worldbuilding never left. Now it's a dark epic in progress — The Swords of Darkness — and a homebrew D&D world I run with frameworks I've spent years refining.

Shooting at Yosemite
03 Photography

Some things I'd rather show than say.

A camera, a single 23mm prime, golden hour. I shoot portraits, fits, and the cities I live in — a month or two at a time. It's the visual half of the same brain that obsesses over color grading and type.

Tokyo
04 Learning & teaching

Learning, taught the way it should be.

I went to CMU, and I still think the best schools teach you to pass exams, not to actually understand things. I'm building courses from the ground up for real learning — math, statistical, and computational thinking — the way I wish someone had taught me.

Osaka
05 Games & the table

Systems you can break.

Balatro proved roguelike deckbuilders are magic — so what happens when you do that to dice? I'm designing one to find out. Same itch as the D&D frameworks and the board game I'm building: take a system apart, find the fun, build it back better.

Weave — the minimalist weight tracker
06 The engine

~160 ideas and counting.

My favorite thing might just be ideating and organizing — roughly a hundred and sixty app, game, business and product ideas in my notes, and a habit of turning the best ones into real, shipped things. Weave (my mom lost 17 lbs with it), a metronome that actually feels good, a tool to find when a show gets good.

Budapest
07 The method

How I learn anything fast.

I pick a skill and go all-in for 30 days. Japanese to A1 in ~20 focused hours. Tone-deaf to singing from memory in one month. Badminton, YouTube, shipping. I research where common wisdom is wrong first, then build the shortest honest path.

Someday

Things I haven't built yet.

  • Write a TV show — I've watched thousands of hours of film and anime, only the best, mostly to take apart why they work.
  • Finish the manga — the "next Death Note or GoT": a complex plot that's somehow easy to follow.
  • Make Westworld real, as a game you can actually live inside.
  • Open a café that's a third place for serious makers — writers, artists, builders, all in one room.
  • Find the talented, curious people I'd do all of the above with.

Writing

The blog

  • How I learn anything in 30 daysessay · soon
  • The year I quit $250k and got happieressay · soon
  • What actually makes D&D peakessay · soon
  • Why schools teach you to forgetessay · soon

Distinct from the work above — ideas, not portfolio. Read the writing →

And some things I do purely for myself — painting like no one will ever see it, building and painting Gundam kits, singing in the mornings, the occasional cosplay. No goal. Just the doing.

Let's build something

I'm looking for people who are excellent at something and curious about everything.

Collaborators, co-conspirators, friends. If any of these worlds is also yours — or you just want to scheme — say hi. The best things in my life started as a five-hour first conversation with a stranger.