early days; founding period; pioneering stage
Refers to the very beginning or initial phase of an organization, field, or movement, often with a sense of pioneering effort.
This company has contributed to the community since its early days.
In the pioneering days of the internet, many engineers went through trial and error.
黎明期 also means 'dawn' or 'early days', but is more literary and often used for historical eras or technological beginnings. 草創期 is slightly more concrete and organizational.
Compound of 草創 (sōsō, 'beginning, founding') + 期 (ki, 'period'). 草創 itself is from classical Chinese, meaning 'to start from scratch'.