GLM 5.3 Prime vs Claude Opus 5.5
GLM 5.3 Prime took 55 min 49 s and $3.43 at list price, Claude Opus 5.5 took 11 min 46 s and $1.57 at list price. GLM 5.3 Prime took 4.7× as long and cost 2.2× as much.
GLM 5.3 Prime
Z.ai · $8.80/M out
Claude Opus 5.5
Anthropic · $20.00/M out · 2,737 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.
Some of the machines we work on were built before any of us were born. Patchbay is a three-person repair studio in Rotterdam, and what we do is simple to describe: we keep vintage synthesizers playing. A Minimoog that sat in an attic for thirty years. A Juno-60 with keys that no longer speak. A modular system that hums where it should roar. Whatever comes through our door gets opened up, traced through, and brought back.
That means rebuilding power supplies, cleaning a thousand key contacts, chasing a fault across three boards until it turns out to be a single cracked solder joint. It means calibrating oscillators that have drifted for decades, and listening — really listening — until a filter sounds the way it did the day it left the factory.
We do this because these instruments still sound like nothing else, and because somewhere a player is waiting to hear one come back to life.
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.
Specs and numbers
| GLM 5.3 Prime | Claude Opus 5.5 | |
|---|---|---|
| Maker | Z.ai | Anthropic |
| Made in | China | US |
| Released | 23 Sep 2026 | 22 Sep 2026 |
| Price in, per M tokens | $2.80 | $4.00 |
| Price out, per M tokens | $8.80 | $20.00 |
| Context | 1,000,000 tokens | 1,000,000 tokens |
| Weights | closed | closed |
| Hacker News points | — | 2,737 |
| Time for the six prompts | 55 min 49 s | 11 min 46 s |
| List price of the six prompts | $3.43 | $1.57 |
Claude Opus 5.5 was cheaper: $1.86 less at list price, and less on 5 of the 6 prompts. Claude Opus 5.5 was faster: 44 min 3 s less in total, and faster on each of the 6 prompts.
In the recording, both Breakout games play. GLM 5.3 Prime's landing page was cut off at the output limit (131,072 tokens).
Rebuild this screen experiment: Claude Opus 5.5's rebuild matched the screenshot at 89%; GLM 5.3 Prime was not in it. Tea Garden experiment: Claude Opus 5.5's game passed 5 of 5 checks; GLM 5.3 Prime was not in it.





