So, I'm not a dev nor a project manager but I found this article very enlightening

Unix and Linux would be your quintessential examples. Unix was an effort to take Multics, an operating system that had gotten too modular, and integrate the good parts into a more unified whole (book recommendation: https://www.amazon.com/UNIX-History-Memoir-Brian-Kernighan/d... ). Even though there were some benefits to the modularity of Multics (apparently you could unload and replace hardware in Multics servers without reboot, which was unheard of at the time), it was also its downfall. Multics was eventually deemed over-engineered and too difficult to work with. It couldn't evolve fast enough with the changing technological landscape. Bell Labs' conclusion after the project was shelved was that OSs were too costly and too difficult to design. They told engineers that no one should work on OSs. Ken Thompson wanted a modern OS so he disregarded these instructions. He used some of the e…

I find it kind of hard to define success or failure. Google search and Facebook are a success right? And they were able to scale up as needed, which can be hard. But the way they started is very different from a government agency or massive corporation trying to orchestrate it from scratch. I don't know if you'd be familiar with this, but maybe healthcare.gov is a good example... it was notoriously buggy, but after some time and a lot of intense pressure it was dealt with.

I heard Direct File was pretty successful. Something like a 94% reported it as a positive experience.

This is a noble and ambitious goal. I feel qualified to provide some pointers, not because I have been instrumental in delivering hugely successful projects, but because I have been involved, in various ways, in many, many failed projects. Take what you will from that :-) - Define "success" early on. This usually doesn't mean meeting a deadline on time and budget. That is actually the start of the real goal. The real success should be determined months or years later, once the software and processes have been used in a production business environment. - Pay attention to Conways Law. Fight this at your peril. - Beware of the risk of key people. This means if there is a single person who knows everything, you have a risk if they leave or get sick. Redundancy needs to be built into the team, not just the hardware/architecture. - No one cares about preventing fires from starting. They do car…

India's UPI (digital payments) is almost as big a scale as it gets, and it's pretty universally considered a success: https://en.wikipedia.org/wiki/Unified_Payments_Interface

I don't think you should focus on successful large projects. Generally you should consider that all big successes are outliers from a myriad of attempts. They have been lucky and you can't reproduce luck. I'd like try to correct your course a bit. DevOps is a trash concept, that had good intentions. But today it's just an industry cheatcode to fill three dev positions with a single one that is on pager duty. The good takeaways from it: Make people care that things work end to end. If Joe isn't caring about Bob's problems, something is off. Either with the process, or with the people. Agile is a very loose term nowadays. Broadly spoken it's the opposite of making big up front plans and implement them in a big swipe. Agile wants to start small and improve it iteratively as needed. This tends to work in the industry, but the iterative time buckets have issues, some teams can move fast in 2 …