[vs2]

The Build HAT is not compatible with LEGO Mindstorms (EV3) because the plug system is different. The Build HAT/SPIKE™ Prime system uses LPF2 plugs whereas the Mindstorms system uses RJ12 plugs.

[_trampeltier]

It can't be long, until Lego start to change the brick size.

[jacquesm]

That's already happened, twice even.

There is 'duplo' and there is 'Modulex':

https://www.newelementary.com/2017/11/old-bricks-what-are-mo...

[thanatos519]

Duplo is Lego-compatible. A 2x4 Lego brick fits exactly onto 1x2 Duplo studs. A Duplo brick is 2x the height of a Lego brick, and a Duplo plate is 1x the height of a Lego brick.

It's fun to build large structures quickly with Duplo then detail them with Lego!

[jacquesm]

There are even ways to connect Modulex bricks to regular Lego, some people have figured out some interesting tricks.

Which allows you to take that strategy to the next level.

[AlanYx]

There was also Lego "Quatro", double the size of Duplo, for very young toddlers.

Only sold from 2004–2006, but still in high demand on the used market. Interlocks with Duplo and regular Lego.

[jacquesm]

Oh cool, never knew about that one. I do have one more to add but it's mostly technics warmed over, which is 'Znap', clearly aimed at the same market as 'Knex', which Lego at some point saw as a competitor. Since then they've come their senses, the Znap line was ugly and highly impopular, leading to being discontinued after only a year.

[makeitdouble]

What if I told you there is another plug type, that might still be sold with some old sets somewhere, and is still supported by a bunch of third party hubs (that for a long time were more advanced in many ways than Lego's own system ...)

Lego's stewardship of all this was a mess, and I'm super glad they open the system to officially blessed third parties.

[bombcar]

There's also all the various rail/train systems, some of which are compatible with some variants ...