The rates in Poland have really risen as of recent (so has the inflation, but that's a different story).

There's a lot of offers in the 120-150 PLN/h (26-33 EUR or 31-38 USD) range; not long ago I had three offers from the top of this range to choose from, and I eventually stayed at my current place since they equalled this rate.

And yes this is wage per hour, because self-employment/B2B is highly popular in IT, for financial and fiscal reasons. After all the deductions, you'd pocket roughly 70% of it.

Once you factor the living cost in: eg. "you would need around 2,827.20€ in Warsaw to maintain the same standard of life that you can have with 5,670.18€ in London (assuming you rent in both cities)" (according to Numbeo), it becomes pretty clear how living and working in Poland can be an attractive deal.

Gross salaries for juniors is usually in the range of 20k annually, in certain companies or software (slave) houses even less. For seniors it should be around 40k. For lead or principals, even managers, around 60k. Consider that net salaries might reach 60% of gross for certain amounts and above (e.g. 60 gross is 36 net). And of course, these are anecdotal data, probably covering 99% of local companies.

My current salary which is close to 6 figures for a tech lead job would be an instant disqualification in probably every local company. To be honest, a few years back it would be a dream for me, unless i had to relocate somewhere. But now and for the next few years, i really cannot see how i can work onsite again in my country.

For Czech republic, based on seniority and skill level I would say between ~$2.5k and ~$7k salary per month before tax. But you lose like a half to the various taxes.