#kotlin
Posts tagged #kotlin on Dynamo Geeks: 6 posts from the community, most useful first.
Posts tagged #kotlin
We moved the Pay button to the bottom and abandoned payments dropped 11%. Payment UX notes for cheap Android phones
Our test phone is a Rp1,5 juta Android: 6.5 inch 720p screen, 3GB RAM, an old mid-range chip. Most of our users have something like it. Most of our designers have a recent iPhone. Ya ampun. Here is what we changed in our payment flow, with numbers. 1. The button moved, abandonment dropped Our Pay button sat at the top right, under the amount, because it looked nice in Figma. On a 6.5 inch phone held in one hand on a…
Finding jank on a Rp1,5 juta phone: what actually worked for our Compose feed
Promised Trey a proper post after his budget Android review, so here it is. Context: big app, Compose UI, and most of our users are on phones that cost Rp1,5 to 2,5 juta (roughly 90 to 160 USD). Our feed felt "fine" on our flagship dev phones. On the cheap test device it was not fine. 1. Measure first, on the right phone Quick check, no setup: adb shell dumpsys gfxinfo com.example.app reset # scroll the feed for 30…
Kotlin coroutines in a Spring service: three leaks we shipped and what structured concurrency fixed
We run our routing service in Kotlin on Spring Boot. Coroutines were introduced two years ago by enthusiastic people, including me. Here are the three mistakes we made, all of them explained in the kotlinx.coroutines docs, which none of us had read properly. Hence the topic. 1. GlobalScope for fire-and-forget fun ship(order: Order) { GlobalScope.launch { auditClient.record(order.id, "shipped") }…
Daraja STK Push from Android: 10 things the docs will not tell you (with Kotlin)
Sasa wasee. I wire up M-Pesa for a logistics startup in Nairobi, from Eldoret. Safaricom's Daraja API works, but the docs leave a lot for you to discover at 2am. Here is my list. Maze, read it before you start. 1. Never call Daraja from the app A consumer key and secret inside an APK is a gift to every bored teenager with apktool. App calls your backend, backend calls Daraja. No exceptions, not even "just for the…
About a minute to the shelter, and coming back from reserve duty to a codebase that moved on
Two stories. Both true. Both about deploys, kind of. One. In Haifa we have about a minute from the alert to the mamad, the safe room, sometimes less. I was in the middle of a rollout, kubectl rollout status running, new pods coming up. Alert. I grabbed the little one, my wife grabbed the big one, laptop stayed on the kitchen table. Ten minutes in the mamad, kids asking if the boom was close, me saying no with the…