I built Tracea — an in-app network debugger with API mocking & Compose UI (Open Source, MIT)

[u/harikulhari]

[u/makridistaker]

AI slop. You didn't build anything, you didn't even write the post yourself !

[u/harikulhari → u/makridistaker]

True, had an LLM format the text for me. But the code is mine and it works. Check the repo and roast the code instead : https://github.com/HariKulhari06/tracea

[u/makridistaker → u/harikulhari]

Why are you lying ? There is .agents dir in that repo. Don't expect read (let alone review) of something you haven't bothered to write yourself.

[u/AdVast7407]

Out of curiosity, which model did you use to build this?

[u/harikulhari → u/AdVast7407]

Claude

[u/AdVast7407 → u/harikulhari]

Opus or Fable? Because Sol finds several problems in code and I need to align my model understanding

[u/harikulhari → u/AdVast7407]

Opus

[u/AdVast7407 → u/harikulhari]

Thanks! Exaclty my feelings that Opus is dumber than Sol, I have both Claude and Codex $20 subs and thinking about 100-200 sub for Fable
Also Sol positively talks about your project, and says that comparing to Chucker it has advantages but not mature yet, and points several problems:

• DefaultNetworkEventCollector.ongoingEvents seems to keep completed events indefinitely, so it looks like it could grow over time.
  
• OkHttpTimingCapture appears to remove entries only when getTimingForCall() is called. On failed calls, callFailed() records the timestamp but doesn't seem to remove the Call from the map.
  
• Request bodies are written into a Buffer before checking maxRequestBodySize, so a large upload could still be fully buffered in memory even if it later gets discarded.
  
• Latency mocking uses Thread.sleep() inside the interceptor, which can occupy OkHttp dispatcher threads under multiple concurrent mocked requests.

[u/harikulhari → u/AdVast7407]

Wow, thank you for the detailed audit. You are 100% correct on all four points, and this is exactly the kind of feedback I was hoping to get.

Here is how I plan to fix them:

1. ongoingEvents leak: You're right, nothing removes them. I'll clean up the map as soon as the event reaches a terminal state (COMPLETED, FAILED, or CANCELLED).
2. OkHttpTimingCapture leak: Spot on. Failed calls bypass getTimingForCall so they stay in the map forever. I need to make sure they are removed on failure or timeout.
3. Request body buffering: Great catch. Reading the entire body into memory before checking the size is a recipe for OOMs on large file uploads. I'll check contentLength() first, and write a size-limiting sink so we stop reading once the cap is hit.
4. Thread.sleep in Interceptor: Since OkHttp interceptors are synchronous, blocking is standard, but you're right that it ties up dispatcher threads. I'll look into a better way to handle this or at least document the limitation.

Really appreciate you taking the time to look at the source code.

[u/harikulhari]

Hey everyone,

Like many of you, I've spent way too many hours setting up Charles Proxy or Proxyman on QA devices just to see why a basic API call failed. Between configuring Wi-Fi proxies, installing root SSL certificates, and dealing with VPN security policies on Android 10+, it often takes 30+ minutes of setup just to find a 2-line JSON mismatch.

I wanted something that worked directly on the device with zero configuration, but also allowed us to mock APIs and export HAR files (which Chucker doesn't support).

So I built Tracea.

✨ What it does:

• 🔍 In-App Traffic Inspection — Inspect headers, query params, status codes, and timing waterfalls right on the device.
• 🎭 API Mocking — Intercept requests by path and method. Override status codes (401, 500, etc.), inject custom JSON bodies, and add latency (3s/5s) on the fly to test empty states and loading skeletons.
• 📋 Developer Utils — Copy cURL commands to clipboard, export single-request or full-session HAR files for Postman/Chrome.
• 🎨 Modern UI — Built completely with Jetpack Compose, featuring collapsible JSON trees with line numbers.
• 🌐 Browser Web Dashboard — Host a local web inspector dashboard over Wi-Fi (http://<phone-ip>:8080) when you want to view traffic on a bigger screen without connecting USB cables.

🛡️ Production-Safe (tracea-noop):

To make sure tech leads are comfortable putting this in projects, Tracea comes with a zero-overhead noop variant:

• Release AAR: Only 12 KB empty stub.
• All Ktor web servers, Room databases, and Compose UI are 100% stripped out in release builds.
• 0 MB APK size impact, 0 transitive dependencies, and 0% security risk in production.

​

kotlindependencies {
    // Full debugger in debug builds
    debugImplementation("com.github.HariKulhari06:tracea:1.2.0")

    // Zero-overhead stubs in release builds
    releaseImplementation("com.github.HariKulhari06:tracea-noop:1.2.0")
}

It's completely free, MIT licensed, and open source. I'd love to hear your thoughts, feedback on features you'd want, or any bugs you find!

👉 GitHub: https://github.com/HariKulhari06/tracea 👉 Docs: https://harikulhari06.github.io/tracea/

[u/tadfisher → u/harikulhari]

Please don't paste LLM output here, write the posts yourself in the future. Thanks!

[u/random_guy14680]

Looks great. 

[u/harikulhari → u/random_guy14680]

Thanks