This comes up all the time and I never understand this attitude.
Yes: dependencies are bad. Not having dependencies and writing everything yourself: also bad.
Honestly, you have to rely on heuristics in your deps. How active is the project? How simple is the thing it's doing (simple enough to probably not have major bugs, but not so simple it's faster to code it yourself) etc.
You get so much velocity from depending on external libs, it's straightforwardly bad not to take advantage of it. Are the junior devs at your company really going to write a better config handling library than the random one from github? Probably not. Maybe they'll both be bad code but the open source one has a better shot of someone else noticing it.
Yes: dependencies are bad. Not having dependencies and writing everything yourself: also bad.
Honestly, you have to rely on heuristics in your deps. How active is the project? How simple is the thing it's doing (simple enough to probably not have major bugs, but not so simple it's faster to code it yourself) etc.
You get so much velocity from depending on external libs, it's straightforwardly bad not to take advantage of it. Are the junior devs at your company really going to write a better config handling library than the random one from github? Probably not. Maybe they'll both be bad code but the open source one has a better shot of someone else noticing it.