Is some part of Tectonic not working? Here are some places to get help.
Search the Forum archives
There is a magnifying glass icon at the top right of every page on this site that will help you search the forum archives. You might find the information you need there.
Search StackExchange (and the rest of the internet)
The tex.stackexchange.com website is an excellent repository of information regarding TeX, LaTeX, and related tools like Tectonic. Quite a few of the problems that people run into aren’t specific to Tectonic itself and will have answers there.
Of course, sometimes questions have been answered on entirely different sets. A general web search of your error message never hurts.
Post a thread here
If you’re not sure what to do, please post a thread in the #help-advice category!
Open a GitHub issue
Many of the problems that people run into aren’t bugs in the Tectonic code, but stem more from questions about how the program is intended to work or how to handle a certain scenario. We tend to think that this website is therefore a bit better forum to ask than the GitHub issue tracker. But if a problem pretty clearly needs a code change to be solved, please go ahead and file an issue on GitHub.