Claude Opus 5.5 vs GLM 5.3 Flash
Claude Opus 5.5 took 11 min 46 s and $1.57 at list price, GLM 5.3 Flash took 59 min 10 s and $0.037 at list price. GLM 5.3 Flash took 5.0× as long, and Claude Opus 5.5 cost 42× as much.
Claude Opus 5.5
Anthropic · $20.00/M out · 2,737 HN pts
GLM 5.3 Flash
Z.ai · $0.148/M out · 1,329 HN pts
Only Claude Opus 5.5 has CLI runs here (Claude Code).
Pelican
Generate an SVG of a pelican riding a bicycle
Watch
Draw a mechanical wristwatch that shows the current local time, with a sweeping seconds hand and a date window. Make it look expensive.
Landing
Build the landing page for Lumen Cycles, a Copenhagen workshop that builds custom cargo bikes to order. Make it look like a real brand you would trust with 4,000 euros.
Breakout
Make a Breakout game I can play right now with the keyboard or the mouse. Give it several levels, a score and some juice.
Logo
Design a logo for Night Heron, an independent bookshop that only opens after dark.
About
Write the opening of the About us page for Patchbay, a three-person studio in Rotterdam that repairs vintage synthesizers. About 150 words.
Patchbay is three people in a narrow workshop near the Maas in Rotterdam. Every day we open up instruments that were built before most of their current owners were born. Some arrive in flight cases and some come wrapped in old bath towels. Most have a story: a Juno that went quiet halfway through a gig, a Minimoog left in someone's attic for thirty years, or a modular system that a previous technician gave up on.
We started Patchbay because we kept seeing good synthesizers sent off as "unrepairable" when all they needed was patience, a schematic and a steady hand. We swap out dried capacitors, hunt for intermittent faults, recalibrate oscillators until they track properly again, and source or rebuild parts that stopped being made decades ago.
We don't try to make old machines sound new. Our job is to make them sound like themselves again, and to make sure they keep working for the next person who plays them.
Patchbay began the way most repair shops do: with a broken synth, a stubborn owner, and a soldering iron that refused to stay idle. We're three people—Joris, Marit, and Tomas—working out of a small workshop on the back streets of Rotterdam-Noord, surrounded by oscilloscopes, spare parts, and instruments that sometimes arrive in worse condition than their owners admit.
Between us, we've spent decades repairing and restoring vintage synthesizers: Rolands, Moogs, Korgs, Yamahas, and machines whose manuals were never written in the first place. We don't sell anything. We fix things. That focus keeps us honest and keeps the work slow, careful, and done properly.
We believe old instruments deserve to keep making music, not gather dust in attics or fetch prices only collectors can pay. Whether it's a cracked keybed, a dying power supply, or a voice that's gone quiet, we'd like to help bring it back.
Specs and numbers
| Claude Opus 5.5 | GLM 5.3 Flash | |
|---|---|---|
| Maker | Anthropic | Z.ai |
| Made in | US | China |
| Released | 22 Sep 2026 | 26 Aug 2026 |
| Price in, per M tokens | $4.00 | $0.016 |
| Price out, per M tokens | $20.00 | $0.148 |
| Context | 1,000,000 tokens | 1,048,576 tokens |
| Weights | closed | open |
| Hacker News points | 2,737 | 1,329 |
| Time for the six prompts | 11 min 46 s | 59 min 10 s |
| List price of the six prompts | $1.57 | $0.037 |
GLM 5.3 Flash was cheaper: $1.53 less at list price, and less on each of the 6 prompts. Claude Opus 5.5 was faster: 47 min 24 s less in total, and faster on 5 of the 6 prompts.
In the recording, both Breakout games play.
Rebuild this screen experiment: Claude Opus 5.5's rebuild matched the screenshot at 89%; GLM 5.3 Flash was not in it. Tea Garden experiment: Claude Opus 5.5's game passed 5 of 5 checks; GLM 5.3 Flash was not in it.





