Building with Claude Code

Learning portfolio

Evolving my product design craft & thinking about how work may change as more people start shipping.

Name Tomomi Sasaki
Updated March 10, 2026
Mood Tired
Notebook
No.NameFor / WhatStatus
04
GestalterGPT A teacher and thinking partner for the use of Gestalt in leadership and organizational development. Ask Tomomi for the link.
iGold peersCustom GPT
Live
05
Emore Cards Interactive ways to explore the Emore Cards from Dignity Inc.
Emotions at WorkWeb app
Private
06
Gestalter - Resistance Reps A scenario-based practice tool for spotting resistance in the workplace.
Coaches and OD peersWeb app
Live
07
Learning Log A set of Claude Skills to generate a topline report of what I did with Claude Code that day
PersonalWorkflow experiment
Live
08
GroundWork A diagnostic tool to identify assertions and assessments
Emotions at WorkWeb app
On pause
09
Solutions Based Coaching A test to see how hard it would be to turn this conversation into an app.
CoachesWeb app
Retired

Where I am

Based in Amsterdam. Working independently as a consultant — mostly with organisations navigating growth, restructures, or the messy middle of culture change.

A good chunk of this year has been spent building: shipping small tools, learning to think in systems, and getting more comfortable at the infrastructure layer.

What I'm working on

  • Gestalter Suite — a set of tools for OD practitioners who want to bring Gestalt principles into their practice without a PhD in theory
  • This portfolio — experimenting with what a learning log in public actually feels like
  • A newsletter archive that treats past writing as something worth finding again

What I'm reading

  • The Timeless Way of Building — Christopher Alexander. Slow going, in the best way.
  • Working in Public — Nadia Eghbal. Thinking about what it means to build things openly.
  • A lot of writing about AI and labour. No single source — more like a fog of takes I'm trying to see through.

What's on my mind

The gap between knowing something intellectually and actually embodying it. I've been a practitioner long enough to know the theory — the harder work is noticing when I'm not living it.

Also: what does craft mean when the tools do more? I don't have a clean answer. But I think the question is worth sitting with rather than resolving too quickly.

Hosting & Deployment

  • Vercel
  • GitHub

Language & Frontend

  • Vanilla HTML/CSS/JavaScript
  • CSS Grid, Flexbox, CSS Variables, CSS animations
  • Astro

Backend Patterns

  • JAMstack — static frontend and Vercel serverless API routes (Node.js)
  • Static JSON files served via serverless API routes
  • dotenv, environment variables

Databases & Storage

  • Supabase — PostgreSQL, RLS, Realtime, Storage (signed URLs)
  • JSON files — static data via API

External APIs

  • Anthropic Claude API
  • Github API

Browser APIs

  • Web Speech API — voice input
  • localStorage, sessionStorage

Libraries

  • D3.js — force-directed network map
  • Fuse.js — fuzzy search

Security

  • CSP + SRI hashes on CDN scripts
  • CORS + rate limiting on API routes
  • X-Frame-Options, X-Content-Type-Options, Referrer-Policy
  • Password hashing (bcryptjs)

Dev Tools

  • Warp
  • Sublime Text
  • Claude Code CLI
  • Vercel CLI
  • gh CLI
  • npm