Note: This article was first published at 9 July 2025.
Today, I’m diving into something a little different than what we normally do here at HardwareZone,but no less geeky: espresso. Specifically, I’m talking about the brand-new WPM Primus espresso machine. If you’re the type who’s fallen down the espresso rabbit hole like I have, then this one’s going to be exciting. You can watch the full video review below, which has some extra bonus material, but if you’re the reading sort, here’s the gist of it:
Manual vs. Semi-auto
To appreciate what WPM has done with the Primus, we need to look at the opposite end of the spectrum—a fully manual lever espresso machine like the Flair 58. It has no pumps, no boilers, no steam wand, no springs or gears: it’s fully human-powered. You grind your beans, boil water separately, fill the tiny brew chamber that’s just about fit for one cup, and pull the shot using nothing but muscle memory. You are the machine.
What’s beautiful about the Flair 58 is its ability to allow something called pressure profiling. Traditional espresso is made at a flat nine bars of pressure. With a manual lever like the Flair 58, you can adjust pressure over time to develop unique flavour profiles, albeit with little consistency or repeatability since no two shots are going to be the same. This is where the Primus come in.
Hybrid Heating and Temperature Stability
Level up your home espresso game.
The Primus is technically a single boiler espresso machine with a clever trick up its sleeve. Instead of relying solely on the boiler to do all the heavy lifting, it combines a smaller 0.8-litre boiler with two PID-controlled thermal blocks—one for the group head, and one for steaming.
The result is a significantly faster heat up time compared to boiler-only machines—around 3 minutes instead of 20-30—and very stable temperatures compared to thermoblock-only machines for back-to-back brewing.
The boiler preheats and maintains water to a mid-point, while the thermoblock fine-tunes it to your target brew temp. This can be adjusted in one-degree increments, ranging from 70°C to 98°C—far more control than most machines in this class.
Even better? You can steam and brew simultaneously, something typically only found on much more expensive dual-boiler systems. Thanks to the dedicated thermoblock for steam, pressure is strong and consistent. You can adjust steam power in the menu, which may help beginners hone their skills, but I find that it’s generally ok to just leave it at the maximum.
Smart Brewing and a Silent Gear Pump
What really makes the Primus special is its touchscreen control interface, fronted by a clean, modern LCD display. There are only two physical buttons on the machine itself—power and steam—plus a paddle to engage the pump. Everything else happens via the screen.
The star of the show is an advanced gear pump, a rare and high-end component not normally found on consumer machines. This is what makes the Primus capable of precise pressure control in 0.1-bar increments, allowing real-time pressure profiling as you brew. It is also whisper quiet throughout the entire supported pressure range (1- to 12-bars) compared to the more commonly used vibration and rotary pumps.
WPM Primus brewing options. Photo: HWZ
You get three brewing modes:
- Full Manual: You control brewing pressure in real-time via the paddle, just like on a lever machine, but with more precision and control. You can go up or down in pressure and the Primus will try to match your target pressure.
- Semi-auto: Preset your pre-infusion and up to four pressure stages (e.g., 1 bar > 3 bar > 6 bar > 12 bar). Engage the paddle to start the shot and manually advance to the next stage while brewing by tapping the touchscreen.
- Full Auto: Preset pre-infusion and up to four pressure stages, including the time (in seconds) for each stage. Engage the paddle to start the shot and the machine will automatically advance to each stage based on the timing set and stop after the last stage.
The Primus will save your brewing history so if you manage to get a god shot one day, you can easily replicate it again. If you’re not feeling too adventurous in the beginning, the machine also comes with a range of preset recipes that you can try to brew with; you can even do traditional flat 9 bar shots if that’s all you need.
Remember, just because the Primus has all these features that allow pressure profiling, it does not mean you have to use it all the time. There is nothing wrong with 9 bars. Taste is personal. Make the drink that tastes best for you.
What the Primus cannot do is brew-by-weight, as there are no volumetric controls nor does it support pairing with Bluetooth scales.
Build Quality and Design Choices
Build-wise, the Primus feels solid and premium. It has a stainless steel body and metal group head, and stainless steel boiler. The external freestanding water tank might be divisive, but it keeps the machine footprint small. Here’s where it gets interesting: the Primus is plumbable (requires a conversion kit), so you can hook it up directly to your water mains. And if you choose this path, you can do away with the water tank completely.
With some clever placement, the water tank never gets in the way.
The only issue I have is the proprietary group head and portafilter design. This means only WPM’s own portafilters work, ruling out aftermarket options; a strange choice considering that the Primus was designed for the enthusiast in mind, and enthusiasts love their accessories. Still, to be fair, it is a 58mm portafilter, so most 58mm baskets do fit and can be used. It’s only the portafilter itself that is proprietary.
While the portafilter is proprietary, it accepts standard 58mm accessories like baskets and puck screens just fine.
Pricing and Final Thoughts
Compact, powerful, advanced, affordable.
The WPM Primus retails for S$2,299, and frankly, that’s a steal for what you’re getting. For context, flagship espresso machines with pressure profiling and dual brew/steam functionality can easily cost twice as much or more. The Decent DE1 starts from US$3,699 (~S$4,700). Even on sale, the Lelit Biance V3 goes for S$4,200 and Sanremo You is S$11,700. Popular machines like the La Marzocco Linea Micra (S$5,200) and Linea Mini (S$7,200) don’t even have pressure profiling.
The gear pump alone is worth the cost of the Primus. Even newer models of Slayer Espresso no longer feature gear pumps, and that’s something that costs in the mid 5-digits range.
Fellow’s upcoming Espresso Series 1 is a solid rival, but it’s not launching until mid-2026, has a much larger footprint and we all know how US pricing translates into SGD when it does make its way to our shores. There are other Chinese brands to look out for such as Wendougee, but they haven’t made their way into Singapore yet.
So is the Primus perfect? Not quite. The proprietary portafilter design isn’t a dealbreaker as you can still use your 58mm baskets and accessories, plus WPM is coming out with its own bottomless, but it does limit aftermarket choice. It also lacks some advanced features such as brew-by-weight, Bluetooth scale and app support, and a temperature probe in the steam wand. In fact, I’d be willing to pay more to have these features included. Maybe WPM will come out with a Primus Pro?
Still, we live in the present, and for the price, features, and build quality? The Primus absolutely one of the most advanced espresso machines available right now. For that, I raise a glass of espresso to WPM.
The WPM Primus doesn’t necessarily make “better” espresso, but it is better equipped to make any style of espresso you might think of, traditional or modern.
You can order the Primus in Singapore from wpm.sg.
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