GLM 5.3 Prime vs GLM 5.3 Flash
GLM 5.3 Prime took 55 min 49 s and $3.43 at list price, GLM 5.3 Flash took 59 min 10 s and $0.037 at list price. GLM 5.3 Flash took 1.1× as long, and GLM 5.3 Prime cost 92× as much.
GLM 5.3 Prime
Z.ai · $8.80/M out
GLM 5.3 Flash
Z.ai · $0.148/M out · 1,329 HN pts
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 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
| GLM 5.3 Prime | GLM 5.3 Flash | |
|---|---|---|
| Maker | Z.ai | Z.ai |
| Made in | China | China |
| Released | 23 Sep 2026 | 26 Aug 2026 |
| Price in, per M tokens | $2.80 | $0.016 |
| Price out, per M tokens | $8.80 | $0.148 |
| Context | 1,000,000 tokens | 1,048,576 tokens |
| Weights | closed | open |
| Hacker News points | — | 1,329 |
| Time for the six prompts | 55 min 49 s | 59 min 10 s |
| List price of the six prompts | $3.43 | $0.037 |
GLM 5.3 Flash was cheaper: $3.39 less at list price, and less on each of the 6 prompts. GLM 5.3 Prime was faster: 3 min 20 s less in total, and faster on 3 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).





