mibuki / Approach

Approach

We build from evidence. Not from hype, and not from willpower — every product decision has to trace back to something you can check.

Who builds to this standard →
01

The premise: nobody gets more time

A day is 24 hours. That number is not negotiable for anyone.

If the problem is “I want to, but I have no time,” the only move left is not to find more hours but to raise the result you get per hour. Once you accept that the supply is fixed, the design question changes: not “how do we get more of your day” but “how much further does the same hour take you.”

So mibuki does not build ways to try harder. We build products that implement the science of efficiency. We do not try to increase how much willpower you have; we increase how far the willpower you already have gets you.

The three principles below are the criteria we actually use. They are not sentiments — they are the rules that decide whether a feature ships.

02

What we will not do

These promises are stronger than the principles, because you can catch us breaking them.

  1. 01

    No unverifiable claims

    No “learn 5x faster.” When we publish a number, the baseline and the measurement sit in the same sentence as the number.

  2. 02

    No dark patterns

    We do not hide the cancel path and we do not place buttons to catch mis-taps. If you want to leave, leaving is easy to find.

  3. 03

    No engagement farming

    No notifications that hold a streak hostage. The number we want to grow is not your time in the app — it is the time you get back.

  4. 04

    No games dressed up as learning

    No reward theatre that makes progress feel real without any learning behind it. If the only thing that moved was a counter, nothing moved.

03

Three principles

Anything we consider building has to pass all three.

01

Effect size over opinion

Choose by effect size

We do not ship a feature because it looks promising. Before adopting a learning method or a behavioural design, we check how large the effect is, whether it replicates, and where it applies. That means reading past the original paper into pre-registered studies, systematic reviews and meta-analyses, depending on what the question needs.

We adopt something because it has been shown to work, not because it is popular. The reverse holds too: if it has not been shown to work, it does not ship, however loud it is. What matters is not the name of the method but who it worked for, by how much, and under what conditions.

02

Remove friction, not add willpower

Remove friction

People do not quit because their willpower is weak. They quit because the design has friction. The number of taps before you start, the number of settings, the number of decisions you are asked to make — all of it decides whether a habit survives.

Instead of telling you to try harder, we delete steps. Fewer settings, usable at defaults, fewer decisions. The goal is a product that needs no willpower at all.

03

Measure it, then publish it

Publish what you measure

If we claim an effect, we publish it in a form you can check. This is a constraint on us, not a feature: if we cannot produce a number, we do not claim a result.

And we do not publish only the conclusion. We publish the baseline, the data and the metric as well, because a number without its conditions can only ever flatter us. A result is ready to publish when a reader could follow the same steps and see the same thing.

04

On advertising

The answer is different per product, so here it is per product, with the reason.

Nothing that interrupts focus or learning carries ads. Lofi Station sells focus; putting something designed to break focus on the same screen does not add up. LangDict is the same case — anything that pulls attention mid-session works against the point of the app.

kikeruka and Atom do carry ads. They are free, and we have not yet built enough of a difference to reasonably charge for a paid tier. Right now there is no way to pay to remove them in either app. When there is a paid tier worth charging for, we will either drop the ads or make them something you can turn off.

So this is not a principle — it is where the products and the funding actually are right now. When that changes, this page changes.

ProductAdsWhy
Lofi StationNoneA tool for focus should not host things that break focus
LangDictNoneNothing that pulls attention away mid-session
kikerukaYes (no way to remove)To keep it free
AtomYesTo keep it free
05

How the principles show up in the products

A principle that is not implemented is not a principle. Here is where each one lands today.

LangDict

Principles
01 + 03
How it shows up
Uses spaced repetition, and publishes how accurately it predicts on public benchmarks

Atom

Principles
01 + 02
How it shows up
Habits designed as minimal units and triggers, following behavioural science

Lofi Station

Principles
02
How it shows up
Focus the moment it opens — the friction of configuration was removed

kikeruka

Principles
02
How it shows up
Scan and wait; checking back is no longer something you have to do
06

References

We list only works whose author, year and venue we have checked against the original.

  1. 01

    open-spaced-repetition. FSRS: Free Spaced Repetition Scheduler. GitHub.

  2. 02

    open-spaced-repetition. srs-benchmark: Benchmark of Spaced Repetition Algorithms. GitHub.

  3. 03

    open-spaced-repetition. anki-revlogs-10k: Anki review logs from 10,000 users. Hugging Face.

  4. 04

    Settles, B., & Meeder, B. (2016). A Trainable Spaced Repetition Model for Language Learning. Proceedings of the 54th Annual Meeting of the ACL.

  5. 05

    Ebbinghaus, H. (1885). Über das Gedächtnis: Untersuchungen zur experimentellen Psychologie. Leipzig: Duncker & Humblot.

Last updated: July 2026