Kotlin 2.0 — 2.3 · Android + iOS

Catch recomposition regressions
before they ship

Rebound instruments Compose at compile time, watches recomposition rates at runtime, and surfaces the result in CI, Android Studio, or the CLI. It is built for teams that want a budget signal, not another profiler window.

Get Started View on GitHub
CI guardrail IDE feedback Fast local checks
build.gradle.kts
plugins {
  id("io.github.aldefy.rebound") version "0.2.2"
}
What you get
CI gate reboundGate
IDE surfaces Monitor / Hot Spots / Timeline
CLI checks snapshot / summary / watch
Maven Central License v0.2.2

Product preview

Android Studio surfaces

Live monitoring, hot spots, timeline heatmap, stability analysis, and session history — without leaving the editor.

Monitor

Live recomposition tree with per-node detail panel showing rate, budget, skip%, and peak values. Sparkline chart visualizes trends over time. Color-coded violation indicators and a real-time event log keep you informed as you interact with the app.

Rebound Monitor tab

Flat thresholds miss the point
same rate, different meaning

Without per-composable budgets, you cannot tell healthy animation-driven recomposition from pathological state thrashing. This table shows the kind of signal Rebound surfaces.

Composable Rate Budget Skip% Status
ShimmerBox 18/s 5/s 0% OVER
MenuItem 13/s 30/s 0% NEAR
DestinationItem 9/s 5/s 0% OVER
TravelGuideCard 8/s 5/s 0% OVER
AppScaffold 2/s 3/s 68% OK

What ships

Rebound instruments at compile time, monitors at runtime, and reports in your IDE. All automatic.

Compiler Plugin

Instruments every @Composable at the IR level. Infers budget class from call-site heuristics. Zero annotation required. Debug builds only.

Budget Engine

Six budget classes: Screen (3/s), Container (10/s), Interactive (30/s), List Item (60/s), Animated (120/s), Leaf (5/s). Dynamic scaling during scroll, animation, and input.

IDE Cockpit

Five-tab Android Studio tool window: live monitor with sparklines, hot spot ranking, timeline heatmap, parameter stability matrix, and session history with VCS correlation.

Install the IDE plugin → · JetBrains Marketplace listing planned

Budget classes

Flat thresholds are wrong for most of your composables. Rebound assigns budgets by role.

3/s
Screen
Full pages
10/s
Container
Row, Column, Box
30/s
Interactive
Buttons, fields
60/s
List Item
LazyColumn items
120/s
Animated
animate* APIs
5/s
Leaf
Text, Icon, Image

Android and iOS

Full KMP support. The compiler plugin instruments all targets. Transport adapts per platform.

📱

Android

ADB socket forward
Device + Emulator

🖥

iOS Simulator

Direct TCP on :18462
Zero setup

📡

iOS Device

WebSocket relay
Bonjour auto-discovery

☕

JVM / Desktop

In-memory metrics
Transport planned

Get started in 60 seconds

1

Apply the Gradle plugin

plugins {
          id("io.github.aldefy.rebound") version "0.2.2"
}
2

Run your debug build

Rebound instruments every @Composable automatically. No annotations needed.

3

See violations

$ ./rebound-cli.sh summary
{"composables":[
  {"name":"ShimmerBox","rate":18,"budget":5,"class":"LEAF","over":true},
  {"name":"MenuItem","rate":13,"budget":30,"class":"INTERACTIVE","over":false}
],"violations":4,"total":127}

iOS Physical Device?

Build and start the relay on your Mac. The device discovers it via Bonjour automatically. 

./tools/build-relay.sh && ./tools/rebound-relay

Try it on a real app

The sample/ module in this repo is a quick-start Compose app with Rebound pre-configured. For a more interesting stress test, try StickerExplode — a particle-effect demo with heavy animation that exercises every budget class.

sample/ module StickerExplode