Simon Callsen

Simon Callsen

Senior UX Designer

7 years at Shopify – now building my own tools in Tokyo.

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Case Studies
Shipping options panel listing Standard and Express ratesRate editor panel with type, price, and transit time fields
Shopify 2025

Shipping Setup Redesign

Untangling years of complexity in one of the hardest parts of setting up a store

Read case study →
Fulfillment settings panel with shipping, pickup in store, and local delivery togglesPhoto of a storefront with glass doors open to the interior
Shopify 2024

Location Delivery Methods

A copy change that turned into a platform change

Read case study →
Order detail card showing a pickup-in-store order with a Transfer required badgeProduct photo of a packaged item from the order
Shopify 2024

Pickup in Store

One out-of-stock item could block the entire checkout

Read case study →

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Personal Projects

Katsuyou Drill

Study tool to practice conjugating Japanese verbs

updated 2 weeks ago
Personal Project 2025
Katsuyou Drill flip-card mode showing the verb 歩く with its English meaning and polite register
Katsuyou Drill type-answer mode showing incorrect te-form feedback for 歩く

TL;DR

Description

The goal was to build a flexible tool for language learners to drill Japanese verb and adjective conjugation.

Features

  • Conjugates verbs dynamically based on the form you select
  • Flip-card and type-answer modes with instant feedback
  • Custom card visuals for each conjugation form
  • Mobile-optimized layout

Tools

  • React + Vite
  • Vocabulary data from the JMdict dictionary project
  • Built end-to-end with Claude Code

Japanese Study

A collection of various tools to help me study Japanese

updated yesterday
Personal Project 2025
Japanese Study vocabulary training list showing weekly word lists and an SRS review queue
Japanese Study immersion reading page showing a news article with simplified text, furigana toggle, and comprehension check

TL;DR

Description

A collection of tools I built to support my own Japanese study.

Features

  • Vocabulary review with spaced repetition (SRS)
  • Immersion reading with a furigana toggle and comprehension checks

Tools

  • React + Vite
  • Supabase (backend and progress sync)
  • Built end-to-end with Claude Code

VN Lookup

Look up Japanese text while playing on a Steam Deck in gaming mode.

updated 3 weeks ago
Personal Project 2025
Steam Deck Quick Access Menu open over a game, showing the VN Lookup panel with captured Japanese dialogue, a word breakdown, and a dictionary entry for 改める with an Anki export button
VN Lookup capture area selection screen with resize handles around a game's dialogue box and controls for auto-detect, move, width, and height
VN Lookup settings panel showing saved capture areas and an Anki integration toggle, with the Jitendex dictionary source listed

TL;DR

Description

A Decky Loader plugin that lets me look up Japanese vocabulary in games without leaving Steam Deck's gaming mode.

Features

  • OCR-based text capture from a configurable on-screen area
  • Word-by-word dictionary lookup (Jitendex) inside the Quick Access Menu
  • No need to exit gaming mode or switch to desktop mode

Tools

  • Decky Loader plugin framework
  • Built end-to-end with Claude Code
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About

I spent 7 years at Shopify designing shipping and fulfillment software, starting as an intern and leaving as a senior designer.

I enjoyed working on larger problems that spanned multiple teams—taking them from initial pitch through to execution.

I'm currently based in Tokyo, going to Japanese language school, and building my own tools on the side. I'm looking for a product design role at an English-friendly company in Japan.

simon.callsen@gmail.com