No software engineering manager at a tech company should spend less than 30% of his or her time coding. Whether managing a team, a division, or all of engineering, when managers spend less than 30% of their time coding, they encounter a significant degradation in their ability to execute their responsibilities.
My claim stands in stark contrast to what I see as the expected path for software engineers who become team leaders. At each promotion, the engineer is expected to spend drastically less time coding, with a particularly steep drop-off when they go from a "lead" to a "manager" title. At that point, they're expected to maintain passing familiarity with their codebase. A director's coding is done, if at all, as a hobby.
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