Tectonic is forked from the XeTeX TeX engine. However, the build process for XeTeX (and all other mainstream TeX engines) is extremely baroque:
1. The original Knuth sources are written in a language called WEB (which is basically used by nobody else)
2. Those sources are then patched with a series of “change files” due to restrictions on distributing modified sources
3. These patched files are then converted to the Pascal language using some custom processing scripts
4. That Pascal code is then converted to C code using additional custom tools
5. Those C files are then compiled against a set of extension files and libraries written natively in C and C++
One of the big motivators for the launch of the Tectonic project was to break out of this ridiculously unwelcoming development process. Tectonic is based on the C/C++ files that emerge from the XeTeX build process, and is gradually translating that code to modern Rust.
While the core TeX architecture and XeTeX are largely stable, they do, however, evolve with time. This repository recreates the final XeTeX C/C++ files from their source, so that modifications can be ported into the main Tectonic codebase.
A tool like this is sorely needed for LaTeX, and Tectonic is especially intuitive to embed into other applications, but the divergence of XeTeX from pdflatex makes it incompatible with most Overleaf projects. This is just an unfortunate ecosystem gripe, but for most workflows I end up having to reach for latexmk instead for this reason.
Background of the project:
Tectonic is forked from the XeTeX TeX engine. However, the build process for XeTeX (and all other mainstream TeX engines) is extremely baroque:
1. The original Knuth sources are written in a language called WEB (which is basically used by nobody else)
2. Those sources are then patched with a series of “change files” due to restrictions on distributing modified sources
3. These patched files are then converted to the Pascal language using some custom processing scripts
4. That Pascal code is then converted to C code using additional custom tools
5. Those C files are then compiled against a set of extension files and libraries written natively in C and C++
One of the big motivators for the launch of the Tectonic project was to break out of this ridiculously unwelcoming development process. Tectonic is based on the C/C++ files that emerge from the XeTeX build process, and is gradually translating that code to modern Rust.
While the core TeX architecture and XeTeX are largely stable, they do, however, evolve with time. This repository recreates the final XeTeX C/C++ files from their source, so that modifications can be ported into the main Tectonic codebase.
https://github.com/tectonic-typesetting/tectonic-staging/blo...
So what does this fork do? No more WEB? No more Pascal? Does it produce exact results as XeTeX?
A tool like this is sorely needed for LaTeX, and Tectonic is especially intuitive to embed into other applications, but the divergence of XeTeX from pdflatex makes it incompatible with most Overleaf projects. This is just an unfortunate ecosystem gripe, but for most workflows I end up having to reach for latexmk instead for this reason.