Django

Polaris invoice screen, halftone

Polaris

Polaris started as client work through Commit Software and turned into the system several retail shops run their day on. It covers the parts a shop touches constantly: invoices and quotations, refunds, stock, customer credit, supplier purchasing, expenses, reports, and the admin around all of it. It’s the project that taught me the edge cases are the product. A billing screen is easy. A billing screen that stays right when two cashiers sell the last item, a customer returns half an order on credit, and a supplier’s price list arrives as a scanned PDF is the actual job. ...

February 10, 2025 · Updated September 2026 · 7 min · Muhammad Hassan Raza
October, typographic cover

October

October is where brands, agencies and creators run influencer campaigns together. A brand or its agency sets up a campaign, brings in creators, agrees on deliverables, tracks the posts as they go live and ends up with a report. I lead the product and wrote most of the backend and frontend. It looks like a dashboard product. Underneath, it’s a permissions problem, a data-honesty problem and a realtime problem at the same time. ...

September 25, 2026 · 3 min · Muhammad Hassan Raza
Bonnet, halftone illustration

Bonnet

Bonnet takes a creative brief (business, audience, competitors, goals, tone) and runs it through research, strategy, creative direction and moodboards, ending in a document a brand team can review and hand on. It was a team project for a client. I owned most of the backend execution flow and a good part of the frontend. Long jobs that stay understandable A full run takes a while. The backend treats it as a series of steps with their own state, streams progress to the browser over websockets, and supports cancelling and rerunning a single step without starting over. The goal was that someone watching it always knows what stage it’s in, what changed on a rerun, and where the output lives. ...

April 8, 2026 · Updated September 2026 · 2 min · Muhammad Hassan Raza
Abstractions and Regrets

Every Abstraction I Regret

The best code I ever deleted was a utility function called format_response. It accepted a response object, a format string, a fallback value, an optional transformer function, and a boolean for whether to strip whitespace. It was used in exactly one place. I wrote it because I thought I’d need it again. I didn’t. It sat in utils.py for eight months, collecting type: ignore comments and confusing every developer who opened the file. ...

April 8, 2026 · 6 min · Muhammad Hassan Raza
Production war stories

I Shipped a Race Condition That Oversold Stock (And Other War Stories)

Most engineering blogs are about things that worked. This one is about things I broke, mostly in Polaris, the retail system I built for shops that bill all day, and one in an AI pipeline at Entropy Labs. These happened between 2024 and 2026. Two cashiers, one item Two cashiers at different counters scan the same product. The shop has one left. Both press “Complete sale” within a fraction of a second of each other. ...

April 8, 2026 · Updated September 2026 · 4 min · Muhammad Hassan Raza

PixelCryptor: Hiding Executables Inside Images

PixelCryptor is a Django app that lets you embed an executable file inside an image. Upload both files, it concatenates them with a delimiter, and stores the result on Azure Blob Storage. You can later extract the original files back out. How It Works The approach is deliberately simple: append the executable bytes to the image bytes with a known delimiter between them. def obfuscate_images(image_blob_name, executable_blob_name): image_data = image_blob_client.download_blob().readall() executable_data = executable_blob_client.download_blob().readall() delimiter = b"---EXECUTABLE_BOUNDARY---" obfuscated_data = image_data + delimiter + executable_data obfuscated_blob_client.upload_blob(obfuscated_data, overwrite=True) Image formats like JPEG and PNG store their data length in headers. Most viewers stop reading at the image data boundary, so the appended executable bytes are invisible when you open the file as an image. Deobfuscation finds the delimiter and splits the bytes back apart. ...

February 16, 2025 · 2 min · Muhammad Hassan Raza
Django performance notes

Polaris Performance Log: The Django Mistakes I Made First

Polaris is the retail operations system I built for shops that bill all day: invoices, refunds, stock, customer ledgers. The first version was correct and slow in the places cashiers notice most. Checkout dragged, refunds dragged, and customers standing at the counter were, to put it politely, fuming a little. None of what follows is clever. It’s a log of the Django habits that looked fine with three test products and fell over with a real catalogue. ...

February 10, 2025 · Updated September 2026 · 4 min · Muhammad Hassan Raza