How to use Claude to build a Mac OS X Tiger app
Claude helped code Uppercut on Mac OS X Tiger, with explicit prompts excluding newer Objective-C features unavailable in Xcode 2.5.
news.ycombinator.com
Prompt to try
Editorial adaptation, not the source author’s exact prompt. Replace bracketed inputs and review tool permissions first.
Help build [native Mac application] for Mac OS X 10.4 Tiger using Xcode 2.5. Use only Objective-C language features supported before Objective-C 2.0. Implement [required workflow], and identify any proposed API or syntax that needs a newer environment before using it.
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See placements →What happened
The author released Uppercut, a native Tiger application that simplifies xbins access to one click, and made its source available on GitHub.
Reported by chadkeck on Hacker NewsHow the agent did it
- Built a native Mac app on an original Intel iMac running Tiger.
- Used Claude to help with much of the application coding.
- Prompted Claude specifically to avoid unsupported newer language features.
Where a person stepped in
The developer supplied specific compatibility constraints. The post does not describe code-review or testing procedures.
A person guided the agent closely as it worked.
A developer built Uppercut, a native Mac application intended to simplify access to the xbins FTP server. The usual process involved connecting to an EFnet IRC channel, messaging a bot for temporary credentials, and entering those credentials in an FTP client. Inspired by Team Resurgent's Pandora, the author made a version suited to an older Mac environment.
Development took place on original hardware: a 20-inch Intel iMac from 2007 running Mac OS X 10.4 Tiger. This was the author's first native Mac application, although they had previous iOS development experience. They used Claude to help with much of the coding.
The key constraint was Xcode 2.5 and the Objective-C features available before Objective-C 2.0. The author had to prompt Claude very specifically to avoid newer language features that the target environment did not support. They noted that much available Objective-C material comes from the later iOS era, making the restriction challenging.
The result was Uppercut, which the author says reduces the xbins connection workflow to one click. Its source was published on GitHub.
Who it's for: Developers exploring native software for legacy Macs who need coding assistance that respects historical toolchain constraints.
Prompt
Suggested prompt (written by Agents In Use, not the author's)
Source: Hacker News · chadkeck
Frequently asked questions
What legacy environment did the author target?
The author used Xcode 2.5 on a 20-inch Intel iMac from 2007 running Mac OS X 10.4 Tiger, with Objective-C features predating Objective-C 2.0.
What does Uppercut simplify?
The author says Uppercut turns xbins access into one click, replacing the manual sequence of obtaining temporary credentials through an EFnet IRC bot and entering them in an FTP client.
More details
Remaining steps
- Published the resulting Uppercut source on GitHub.
About this account
Claude assisted with much of the coding within constraints supplied by the developer for the older toolchain.
Platform: Hacker News. Attribution: https://news.ycombinator.com/item?id=42809518. Prompt: Suggested (written by Agents In Use, not the author's). Sourced by the Agents In Use pipeline.
Credit: chadkeck on Hacker News
Source published 24 Jan 2025
Source checked 14 Oct 2026
Tools and topics
Claude · Xcode 2.5 · Mac OS X 10.4 Tiger · Objective-C
Legacy development · Objective-C · macOS
Editorial completeness: 100/100. Measures documented fields, not agent performance or verified outcomes.