Currently the going annual salary for a senior developer in Bulgaria (Eastern Europe) is somewhere between EUR 50k - 75 EUR net, with 25-30 days of paid time off. The gross will be about 25% more (income tax is 10%, social security around 40%, but there is a cap on the salary base, so effectively it is less). For freelance senior developer, the (B2B) daily rate is in the range EUR 350 to EUR 550, depending on the technology and project complexity. Of course, there are rare examples outside of these ranges (e.g. top talent in ML, BigData etc). Leadership roles are usually at 10-20% premium.