Claude Code use cases: 74 real examples

A prototype took two evenings and a live game six weeks; after seven weeks it had 164 players, 109 active in one day.

The robot navigated, scanned rooms, kept memory notes, and published a patrol field journal, but spent 15 minutes parking at the wrong door.

The operator reports +19.04% versus +12.24% for the S&P 500 from March 3 to August 4, 2026, with $27 million copying the trades.

A working balloon camel simulator with multi-balloon twists and model export, published as the CamelKoons repo, though the look ended up off-target.

Claude gave failed builds for a week and used up the 20x Max weekly limit. Sol had worked 20+ hours without success.

A test run processed 40 PDFs, created the QuickBooks records, attached the PDFs, and cleaned up automatically, cutting hours to minutes.

Within 90 minutes Claude produced a functional proof of concept confirming an authentication bypass across four tested endpoints.

About 1,570 entries posted in Claude Code alone, and Codex caught a VAT return error days before filing.

Claude found 25 to 30 people with sources; the author emailed about 20, and 7 replied, several with intros and new leads.

Cantillon claims Claude found about $700 in savings on the first day, according to the article's headline.

Claude pulled 60 documentation pages into local Markdown files in about 49 seconds, including roughly 10 seconds of backend cold start.

It cost about two months of Pro subscription over half a working day, and ended up slightly slower than doing the migration by hand.

The repo shows sample decks, Word documents, and Excel workbooks, all created by agents with no templates and no manual editing.

All three produced a playable multiplayer game with a map list and saved rooms; Opus won on visuals, Gemini on backend, Codex landed in between.

A 6:49 narrated video with subtitles, an annotated PGN, and a standalone HTML analysis board for one real lichess game, all included in the repo.

Claude handled analytics, pricing, staffing and simple stall placement well, but failed at pathways, large coasters, and vertical terrain. The mod took about 40 hours.

About 19k lines of Rust across 154 commits in three days. The engine passes 64 SQLLogicTest queries and 282 AI-written unit tests.

A camera automation that fired 5 times in 40 minutes was fixed in under two minutes, and shed motion lights were built.

The author finished most of their tax prep in about three hours, work they say would have cost $1,000 from an accountant.

Shipped llm-coding-agent 0.1a0 to PyPI with six file and shell tools, a CLI and a Python API; it built a working ASCII-art clock app.

The author reports faster literature search, Zotero notes written automatically, and accurate answers about the ATS hydrology codebase through a custom ats-mcp server.

Five mp3 songs were published, including a twelve-song album concept and a five-movement symphony, with MIDI and lyrics in public repos.

The Lex support automation built this way has 15 scripts and 6 templates, and handles about 80% of support tasks with yes/no approvals.

It produced a report with BPM (~91), 4/4 meter, B major key, 50 onsets, a four-section timeline, and a stem list.