Show HN: CLI to order groceries via reverse-engineered REWE API (Haskell)

35•wazHFsRy•2d ago

I just had the best time learning about the REWE (German supermarket chain) API, how they use mTLS and what the workflows are. Also `mitmproxy2swagger`[1] is a great tool to create OpenAPI spec automatically.

And then 2026 feels like the perfect time writing Haskell. The code is handwritten, but whenever I got stuck with the build system or was just not getting the types right, I could fall back to ask AI to unblock me. It was never that smooth before.

Finally the best side projects are the ones you actually use and this one will be used for all my future grocery shopping.

[1]https://github.com/alufers/mitmproxy2swagger

Comments

wklm•1h ago

Nice! Do you know if the Austrian billa (REWE's subsidiary) is using the same api?

fractallyte•29m ago

My friend works at Billa AT; I could ask her – but that would be cheating ;-)

Dominik1001•50m ago

Very cool! Thanks for sharing, I’ll try it out.

Haskell is indeed an interesting choice. ;)

kls0e•5m ago

this feels a bit like Sandra Bullock ordering pizza in „The Net“, impressive

Claude Code Unpacked : A visual guide

CERN levels up with new superconducting karts

Neanderthals survived on a knife's edge for 350k years

Show HN: CLI to order groceries via reverse-engineered REWE API (Haskell)

Bring Back MiniDV with This Raspberry Pi FireWire Hat

TinyLoRA – Learning to Reason in 13 Parameters

A dot a day keeps the clutter away

Show HN: 1-Bit Bonsai, the First Commercially Viable 1-Bit LLMs

TruffleRuby

MiniStack (replacement for LocalStack)

The Claude Code Source Leak: fake tools, frustration regexes, undercover mode

Digitizing photos from the 1998 Game Boy Camera

OpenAI closes funding round at an $852B valuation

Chess in SQL

Remembering Magnetic Memories and the Apollo AGC

4D Doom

Slop is not necessarily the future

Open source CAD in the browser (Solvespace)

Why the US Navy won't blast the Iranians and 'open' Strait of Hormuz

Analyzing Geekbench 6 under Intel's BOT

Ordinary Lab Gloves May Have Skewed Microplastic Data

Back to FreeBSD – Part 2 – Jails

Teenage Engineering's PO-32 acoustic modem and synth implementation

Butterfly-collecting: The history of an insult (2017)

Cohere Transcribe: Speech Recognition

Axios compromised on NPM – Malicious versions drop remote access trojan

Joel Meyerowitz on Photographing Giorgio Morandi's Studio

Show HN: Postgres extension for BM25 relevance-ranked full-text search

From 300KB to 69KB per Token: How LLM Architectures Solve the KV Cache Problem

Learn Something Old Every Day, Part XVIII: How Does FPU Detection Work?

Show HN: CLI to order groceries via reverse-engineered REWE API (Haskell)

Comments

Claude Code Unpacked : A visual guide

CERN levels up with new superconducting karts

Neanderthals survived on a knife's edge for 350k years

Show HN: CLI to order groceries via reverse-engineered REWE API (Haskell)

Bring Back MiniDV with This Raspberry Pi FireWire Hat

TinyLoRA – Learning to Reason in 13 Parameters

A dot a day keeps the clutter away

Show HN: 1-Bit Bonsai, the First Commercially Viable 1-Bit LLMs

TruffleRuby

MiniStack (replacement for LocalStack)

The Claude Code Source Leak: fake tools, frustration regexes, undercover mode

Digitizing photos from the 1998 Game Boy Camera

OpenAI closes funding round at an $852B valuation

Chess in SQL

Remembering Magnetic Memories and the Apollo AGC

4D Doom

Slop is not necessarily the future

Open source CAD in the browser (Solvespace)

Why the US Navy won't blast the Iranians and 'open' Strait of Hormuz

Analyzing Geekbench 6 under Intel's BOT

Ordinary Lab Gloves May Have Skewed Microplastic Data

Back to FreeBSD – Part 2 – Jails

Teenage Engineering's PO-32 acoustic modem and synth implementation

Butterfly-collecting: The history of an insult (2017)

Cohere Transcribe: Speech Recognition

Axios compromised on NPM – Malicious versions drop remote access trojan

Joel Meyerowitz on Photographing Giorgio Morandi's Studio

Show HN: Postgres extension for BM25 relevance-ranked full-text search

From 300KB to 69KB per Token: How LLM Architectures Solve the KV Cache Problem

Learn Something Old Every Day, Part XVIII: How Does FPU Detection Work?