! LaTeX Error: File `slashbox.sty' not found

I try to switch to tectonics but it doesn’t seems as easy as thought. the package slashbox is not found

! LaTeX Error: File `slashbox.sty’ not found.

where can I place the file for tectonics to find

Thanks tschinz

While I can reproduce the problem on the example file, this package is so old (almost 30 years) that it doesn’t surprise me that it doesn’t work right away with Tectonic. I did not look into the cause of the error, but I took the example from http://mirrors.ctan.org/macros/latex/contrib/slashbox/slashbox.tex and this is what pdflatex gives me:

          Entering LaTeX 2.09 COMPATIBILITY MODE
    !!WARNING!!    !!WARNING!!    !!WARNING!!    !!WARNING!!   
 This mode attempts to provide an emulation of the LaTeX 2.09
 author environment so that OLD documents can be successfully
 processed. It should NOT be used for NEW documents!
 New documents should use Standard LaTeX conventions and start
 with the \documentclass command.
 Compatibility mode is UNLIKELY TO WORK with LaTeX 2.09 style
 files that change any internal macros, especially not with
 those that change the FONT SELECTION or OUTPUT ROUTINES.
 Therefore such style files MUST BE UPDATED to use
          Current Standard LaTeX: LaTeX2e.
 If you suspect that you may be using such a style file, which
 is probably very, very old by now, then you should attempt to
 get it updated by sending a copy of this error message to the
 author of that file.

The package is really small though, so if you are skilled enough at LaTeX you should be able to make it work with minor modifications. Good luck.