I have a Wi-Fi access point cAP ac, but after installing the latest version of RouterOS along with the wifi-qcom-ac firmware package, I am left with very little free flash memory.
Is there any way to slim down the RouterOS image? I can see that the .npk files look like compressed archives, so maybe it’s possible to remove unnecessary components, such as firmware files that are not required for this specific hardware platform?
It seems like this is your first time on the forum,
or you haven't read anything that's already been written in DOZENS of other posts...
Is It possible to reduce the size of system image?
NO.
Currently ANY other answer, other than putting v6 back / use wireless package, is wrong.
Basically: no.
This is a well-known issue with these devices. With care you can limit the amount of flash used for other purposes (logging to disk, graphing stored to disk, storing dhcp leases, large address-lists). Being careful with this is more of an obligation than an option, really. The somewhat good news is that with care, they are stable.
Another thing is that upgrades tend to leave some configuration behind, so not upgrading frequently and/or netinstalling them seems to help.
Just for reference: a hap ac2 (same platform) has around 392 KB free after a fresh netinstall on 7.20.8. So you're really not doing that badly.
If you want space (and RAM) back, return to the "wireless" package.
Anyway, no one should need more than 640, err..., 392 KB.
You sure? hAP ax² has 128M, not 16M.......
Of course not. AC2.
You edit the post later 
Yeah. Thanks for pointing it out! (I didn't mean the response to be flippant. The correction was a result of your post.)
Too many acronyms, I'm wrong too...
In fact, one way to avoid running out of memory ANYWAY just after some week is to disable everything that writes to internal memory:
(I'm going from memory, this is an incomplete list)
The list is useful, and a good start for anyone trying to hunt down where free space is vanishing.
I have a few ac2's, and one of them that is in constant use, and was last netinstalled 2 years ago, after two upgrades (in-place) still has 304 KiB free. It has address lists (though less than 100 total entries), logs to disk (with a small limit), stores graphs (but only a few that I found useful) and writes dhcp leases to disk...
So, if one is aware of the problem, it's very possible to live with it.
MikroTik could make a "lite" variant of wifi-qcom-ac with the firmware that is only used for the RB4011 and Château Audience devices removed, and wifi-qcom-ac.npk's size will be reduced by about 500KB. That was suggested to them since 7.15 or so, but they refused to do that.
It is the RB4011iGS+5HacQ2HnD-IN and Audience that use QCA9984 for wireless. All other wifi-qcom-ac compatible devices (e.g. Chateau, cap ac, ...) use IPQ-4018 wireless chipset. As the RB4011 and Audience both have 128mb NAND, these can keep using the full wifi-qcom-ac.npk. But for the remaining devices, which all have 16mb flash in common, there would be nice to have a wifi-qcom-4018.npk or something.
Yeah, a separate wifi package for just these devices would have been a nice touch. On the other hand, the 128 MB of RAM is also somewhat tight for the new driver... and they did significantly reduce the main package size for arm along the line... so, while not ideal, it's definitely usable. And these devices are slowly getting phased out anyway.
I have a more significant worry about support going forward. I'm sure that they will make sure that further versions also keep to the current footprint, but I don't know how this will affect feature availability for the newer ARM devices with 128 MB flash. We've seen that the L009 was upgraded to ARM64, but I'm not sure if that will happen to the MediaTek line.
If one is willing to forget about WiFi part of hAP ac2, this device makes a very decent wired router (the cAP ac less so due to weird form factor and lack of RJ45 ports). And if one removes wifi-qcom-ac package, flash has healthy portion of free space (mine reports 2472.0KiB free space).
Thanks, I've forgotten the name 
I've updated my post with the correct name.
Yes, that's how I am using the hAP ac², it even runs a UDPXY container for IPTV. Works very well as wired router for 1Gbps WAN for which it has no problem (both IPv4 & IPv6, with Fasttrack enabled).
Veeeeeeeeeeeeery slowly!
I have seen only one dead hAP ac2 ever, all the others (maybe 50-60 that I manage) are still doing just fine. A few of them got new power supplies, a few needed netinstall, but otherwise there is no real reason to change (“phase out”) them and make more trash than necessary.
Eventually they will reach a stage that they cannot be upgraded any more, but then they’ll just remain on last working version…
Or Wifi-7/8/9/whatever will become as normal as now is 5GHz which forced me to abandon my last Linksys WRT54GL last year 
, so people will actually need to “phase out” them…
Agreed. By "phased out" I only meant that they will stop being sold.
I also have quite a few of them, though not as many as you. I'm hopeful that Mikrotik will follow their usual way of doing things, and provide updates for them (almost) indefinitely.
