Notes from building the templates.
Step-by-step guides on Flutter, Compose and shipping to the stores. Written while solving the problem, not after.
Background Location in a Rider App: The Permission Is the Easy Half
The stream stops when the screen locks and nothing throws. The foreground service type Android 14 wants, the flag iOS wants, and the form a human at Play reads before any of it ships.
2 Sep 2026 · 13 minFive Ways to Launch a Delivery Marketplace, Honestly Compared
White-label, template, agency, in-house, no-code. What you own in each, what it costs by year three, and what you are physically holding on the day you decide to leave.
25 Aug 2026 · 11 minBuild or Buy a Delivery Marketplace: A Template Saves the Boring Two-Thirds
Thirty-five engineer-weeks of solved problems is what you are buying. Dispatch tuning, zone design and unit economics are not on that list, and no template ships them.
25 Aug 2026 · 10 minDelivery Zones in PostGIS: Stop Storing a Radius
A circle accepts the flat across the river and refuses the estate down the dual carriageway. Polygons, geography over geometry, and why ST_Contains is the wrong function.
25 Aug 2026 · 12 minStripe Connect: The Charge Type Decides Who Eats the Chargeback
Direct, destination, and separate charges and transfers are not three styles of the same thing. They decide whose balance a dispute comes out of, and only one splits a cart.
25 Aug 2026 · 13 minOrder Status over FCM: The Notification Is Not the Source of Truth
Messages collapse, arrive out of order and never arrive at all. Send the order id and refetch, why Apple rejects the priority you set, and the token rotation that fails quietly.
25 Aug 2026 · 12 minAssigning Orders to Riders: Why Nearest-First Is the Wrong Algorithm
Dispatch is a matching problem, not a search problem. A three-second batch window, a cost function measured in seconds, and the Routes API bill that catches everyone.
12 Aug 2026 · 12 minWhat It Costs to Run a Multi-Vendor Delivery App: Firebase and Maps, Line by Line
Current Firestore, Realtime Database and Google Maps pricing applied to a thousand orders a month. The same app bills $21 or $1,770, and one await decides which.
12 Aug 2026 · 12 minSplitting a Cart Across Multiple Vendors: Data Model and Checkout Flow
One cart, several sellers, one payment, and every vendor fulfilling independently. The schema that makes it work, and the three places it usually breaks.
11 Aug 2026 · 11 min