Simon Callsen

Consolidated scattered rate conditions into a single "shipping option" — a foundation later project milestones built directly on.

Challenges

• Shipping setup reflected the backend data model, not how merchants actually think about pricing
• A longer-term flexibility goal couldn't be reached without untangling that model first
• Had to stay aligned with other shipping projects shipping in parallel
• Ship improvements over defined milestones that incrementally deliver value

Solution

• Consolidated scattered conditions into a single object: a "shipping option"
• New shipping option evolves with following project milestones

Outcomes

• The first two milestones have shipped
• The second announced in Shopify's Spring '26 Edition as Advanced Shipping Options
• The third milestone is in public developer preview as Market-driven shipping

Replaced a single ambiguous checkbox with an explicit Fulfillment section showing every delivery method's on/off status, location by location.

Challenges

• The old logic could silently add shipping rates after creating a new store location, which was not always the right choice
• This wasn't communicated to users
• Other methods like local pickup were not surfaced at all
• We had to balance low scope while delivering merchant value

Solution

• Replaced the old setting with a dedicated section that shows, for each location, the clear on/off status of every delivery method — shipping, local delivery, in-store pickup — all in one place.
• Removed the automatic behavior completely, so nothing changes unless the store owner chooses it.

Outcomes

• Shipped in Shopify's Summer '25 Edition as "Consolidated view for delivery methods"
• Done in parallel with the Shipping Setup Redesign, covering the end-to-end merchant experience

Rebuilt in-store pickup feature to add key use cases and allow for 3rd party extensibility

Challenges

• One missing item at a location would block pickup for the whole order, even if the merchant could transfer it from another location.
• Locations hundreds of kilometers away in foreign countries would show up as valid pickup locations
• Large merchants needed to be able to replace our logic with their own custom pickup logic

Solution

• A pickup location can now pull inventory from another location instead of blocking the order over one missing item.
• Checkout now prioritizes nearby locations, warns when the closest one is still far, and hides locations outside the buyer's country.

Outcomes

• Shipped as Store Transfers, announced in Shopify's Summer '24 Edition
• Some of the confusion this created was later addressed in Location Delivery Methods

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

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