I suspect there is memory leak. Or just huge memory consumption?

Originally build script took about 2gb memory during build.
After adding react query in one component it increased to well above 2.
I noticed it because build crashed with heap out of memory on 2gb ram (fixed by using max old memory flag).
And after I added react query in another place, it filled 2 ram + 3 swap almost entirely.

How can I test it on local machine reliably?
On windows

Tried this, but it is not working. Prints 40mb, so it seems it is not picking up child processes of build script

import { spawn } from 'node:child_process'

const child = spawn('npm', ['run', 'build'], {
    stdio: 'inherit',
    shell: true,
})

setInterval(() => {
    const memoryUsage = process.memoryUsage()
    console.log('\nMemory usage:', {
        rss: `${Math.round(memoryUsage.rss / 1024 / 1024)} MB`,
        heapTotal: `${Math.round(memoryUsage.heapTotal / 1024 / 1024)} MB`,
        heapUsed: `${Math.round(memoryUsage.heapUsed / 1024 / 1024)} MB`,
    })
}, 5000)