The most important and hardest bit to get right on a CV is explaining briefly, what you have got done that had an impact on the bottomline of your employer. The following format works well for this: *accomplished X measured by Y by crafting Z*. In a talk I once summarized the most important details what recruiters expect from a CV – here the timestamped video: https://youtu.be/5hsTnTeZk-k?t=676. Also, a good blogpost on this topic is 5 Tips For Developers CV.
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