Hara Hachi Bu — 80% Instead of 100% as Indie Builder Discipline

TL;DR

Hara Hachi Bu (腹八分目) is the Okinawan rule of thumb to stop eating at 80% fullness. Applied to indie building: do not plan every hour of the day, do not take every commission, do not chase every growth offer. In my eight-projects-parallel workflow this lives concretely as a 90-minute slot hard-cut + max ~6.7 productive slots per day. Reserves are not luxury — they are the reason 8 parallel projects work at all instead of crushing each other.

Featured: stylized bowl, 80% full. The point where restraint begins.

Table of Contents

• What Hara Hachi Bu actually is
• The Okinawa study as data basis
• Translation to indie workflow
• Why 80% produces more output than 100%
• Three concrete 80% disciplines
• When 100% is still necessary
• FAQ

What Hara Hachi Bu actually is

Hara Hachi Bu (literally “stomach eight parts”) is a Confucian-Buddhist maxim that has become daily practice in Okinawa. It is traditionally spoken before every meal: eat until you are 80% full, then stop.

The logic: The body’s satiety signal needs ~20 minutes to travel from the stomach to the brain. If you eat until you feel full, you have already eaten too much. Stopping at 80% means reaching full satiety roughly 20 minutes later — without overfeeding.

This is not a spiritual concept. It is biological latency compensation, put into language.

The Okinawa study as data basis

Hara Hachi Bu is one of the central lifestyle practices identified in the Okinawa Centenarian Studies (begun in 1975 under Dr. Makoto Suzuki and Bradley Willcox) as a possible factor in Okinawan longevity.

Concrete data from the study:

• Okinawans historically consumed about 1,800-1,900 calories per day — compared to the mainland Japan average of ~2,200.
• The rate of centenarians in Okinawa is 3-5× higher than the global average (World Health Organization 2010).
• Correlative evidence suggests that caloric restriction (of which Hara Hachi Bu is a daily-life-compatible form) extends lifespan in many animal species (National Institute on Aging review 2018).

Important: the study shows correlation, not causation. Hara Hachi Bu is part of a broader Okinawan lifestyle (movement, social embedding, healthy nutrition). But the principle itself — deliberately stopping below maximum — is robustly isolable.

Translation to indie workflow

What applies to food applies analogously to work. Three direct translations:

1. Daytime utilization: 80%, not 100%

In my eight-parallel-projects workflow, 6.7 slots per day is the median. At 90 min per slot + 15 min break = 105 min × 6.7 = 11.7 hours of day-time.

From wake-up at 06:30 to hard cutoff at 21:00 = 14.5 hours. 6.7 slots / 14.5 available hours ≈ 80%.

That is not coincidence but Hara-Hachi-Bu discipline. The remaining 20% (2-3h) are:

• Sunday walk
• Lunch
• Short walks between slots
• Reading without a screen

Not “break as weakness.” Break as construction element.

2. Commission acceptance: not every one, not all

Since 2024 I consistently decline ~30-40% of inquiries. Not from arrogance — from restraint discipline. Anyone accepting everything that comes in is running a volume business. Indie builders with volume business stop being indie.

Heuristic: if a commission would push me toward 100% utilization, it gets declined. Even when financially attractive. Reserves are more important than margin.

3. Project count: 8 is not 12

I could mathematically hold more projects in parallel — the tooling infrastructure (Conductor, knowhow plugin) would allow it. But I deliberately set the maximum at 8.

At 12 I would:

• Switch between domains more often (context switching is the most expensive operation)
• Reach less depth per project
• Accumulate more maintenance debt

At 8 the 20% reserve remains for unforeseen depth. When Bonblick suddenly needs a reality check, I can run 2-3 days at 80% Bonblick without dropping other projects.

Why 80% produces more output than 100%

At first glance “80% instead of 100%” sounds like less output. Empirically it is more.

Three mechanisms:

Mechanism 1: Error avoidance

At 100% utilization there is no buffer time for correction. A bug lands in main. A compliance detail gets overlooked. A customer call goes badly. Correction costs are higher than the original time saved.

In my what-does-not-work-in-agentic-coding telemetry, 5-8 bug incidents in 18 months are directly 100%-utilization-induced. With earlier Hara-Hachi-Bu discipline, they would have been ~2-3.

Mechanism 2: Idea capacity

Good indie ideas do not arise in concentrated work slots. They arise in the breaks between — on walks, in the bath, in cafés. Cal Newport describes this in “Deep Work” as “diffuse mode” thinking.

At 100% utilization there is no diffuse mode. At 80% there is. The Logbuch & Lotse concept idea came to me during a Sunday walk, not in a slot.

Mechanism 3: Self-repair time

ADHD hyperfocus (see ADHS-mit-59) is efficient but destructive when run without recovery. Hara Hachi Bu forces 20% self-repair time:

• Sleep without effort
• Eat without reading code on the side
• Walks without audio podcast

That keeps hyperfocus usable across years rather than across weeks.

Three concrete 80% disciplines

If you want to test Hara Hachi Bu in your own workflow:

Discipline 1: Weekly slot counter

Track for 4 weeks the number of your productive 90-min slots per day. If the median is > 7.5, you are running at 100%+. Deliberately reduce to 6.5-7 for 2 weeks. Observe: has output changed qualitatively? In my case: yes, noticeably better.

Discipline 2: Commission filter

Before accepting a new commission, ask: “Does this commission bring me closer to 100% utilization?” If yes → no. If your gut says “I need the money” — that is a different conversation (liquidity strategy), not a restraint question.

Discipline 3: Weekend hard cutoff

At least 1 day per week completely offline. Not “I just check mail briefly.” Completely. For me: Sunday. For you maybe Saturday. Doesn’t matter which — consistency matters more than weekday.

When 100% is still necessary

Three situations where Hara Hachi Bu does not apply temporarily:

Situation 1: Existence crisis

Acute money shortage, looming insolvency, personal emergency. In these phases do not hold restraint — fight. But: that is temporary. Anyone running 6+ months at 100% has no crisis but a structural problem.

Situation 2: Launch sprint

Real product launch with hard deadline (Demo Day, investor pitch, conference demo). 2-3 weeks at 100% are survivable — if a 80%-reserve recovery week explicitly follows.

Situation 3: Learning sprint

Picking up a new technology/domain in 2 weeks. Here hyperfocus 100% is not just OK but necessary. But: 2 weeks, not 6. And with a clearly defined end point.

In all three cases an explicit return-to-restraint point must follow. Otherwise the exception becomes a permanent mode.

Where this goes next

My next Hara Hachi Bu step: less commission volume for Moinsen consulting, more share of own indie products. The indie products are currently pre-revenue — that is, Hara Hachi Bu costs me money short-term to preserve the reserves for long-term indie growth. That is the uncomfortable version of the 80% discipline.

If you struggle with 100% utilization and want to test the 80% principle: reach me on LinkedIn. Experience exchange helps.

FAQ

Isn’t 80% just laziness?

Empirically no. 80% utilization with continuous output quality beats 100% utilization with bug incidents, sick leave, and bad decisions. That is not laziness; that is efficiency with buffer time.

Does Hara Hachi Bu work in corporate jobs too?

Harder. Anyone with 8-hour office hours is structurally set at 100% (presence = utilization). Hara Hachi Bu in a corporate job is more mental discipline — not all tasks tackled at equal intensity. Truly free restraint discipline exists only as self-employed.

How do I measure if I am running at 100%?

Three indicators: (1) weekend exhaustion instead of recovery, (2) error rate in output rises, (3) creative ideas become rare. If 2 of 3 apply: 100% risk.

Which book do you recommend?

Dan Buettner: “The Blue Zones — Lessons for Living Longer From the People Who’ve Lived the Longest” (2nd ed. 2012) — the canonical study on Okinawan longevity. Hara Hachi Bu is described there as one of nine principles.

Can I apply Hara Hachi Bu to eating too, to understand the effect?

Yes, that is the original application. Try 2 weeks: before every meal, remind yourself of “80% satiety,” put down utensils at the first sign of fullness. You will observe how the body stabilizes 15-20 min later. That experience then translates well to the work equivalent.

Written on May 17, 2026 in Hamburg. Hara Hachi Bu is one of the most practicable of the eight principles — low-threshold to apply, biologically grounded. If you find this post useful, link to it.