Maintain one source of truth, the second one is not wrong, yet. Repeat yourself as re-usable classes easily become Frankenstein code. Don't overuse mocks because test code is extra code to understand and not prod-level. Minimize mutable state since it's cheaper and you don't have to worry about conflict and state.
Engineer's CodexPay on-callers according to the load and time it costs them. Your team objective is making complex systems reliable. Ensure skills, load, schedule, and notifications are at the right level. Welcome new-comers by simulating then shadowing then reverse shadowing. Rotate 2 or more builders to be on-callers as they know the system better and there isn't a single point of failure. Tools and vendors come and go, technology evolves, what matters is that you have a capable team. Respect OoO (Out of Office) while still having 100% on-call coverage by planning ahead, cross-training team-members, documenting a lot, reviewing energy, and adjusting. Cultivating a culture that prioritizes employee’s well-being decreases burnout substantially, while improving employee satisfaction and increasing productivity significantly.
RootlySoftware development is a creative process, not a scientific one, and creative endeavors cannot be distilled down to knowable steps and a repeatable system. Software challenges are creativity-related: desires, personalities, dynamics and understandings. You can't estimate software projects well because the laws of engineering don't apply here. We'll forever be unable to estimate software projects deadlines and customer will still seek out vendors who will tell them what they want to hear, even if it is complete baloney. Software development is not an engineering discipline but a process mired in changing human desires, interacting personalities, dynamics and shifting customer understanding.
Nick HodgesYou don't have that much 10x work days per year. Daily routines are 1x or even .5x work. It's unclear how 10x work happens but it's clear that it happens away from routine. Execute your day out of novelty, risk, and by your plan rather than reacting to others help. Serendipity loves randomness and hates routine so don't hesitate to reach out to interesting people by various ways, research, exchange.
Andrew Chen