LaTeX

Opening a .tex file in Scient opens it as a live LaTeX document instead of plain source: a source view, a split view with the compiled PDF alongside your editing, and a PDF-only view. Switch between them, and drag the divider in split view to resize either side.

Builds happen automatically — save the file and Scient compiles it. Errors and warnings from the build appear in a list above the document; each one shows the file and line it came from when the compiler reported one. Click a message that names a project file to open that file at the reported line.

In Split, double-click a line of source to jump to the matching place in the current successful PDF. Double-clicking a word in the PDF keeps the normal word selection and reveals the corresponding source line in the source pane. These gestures never open Split automatically; select Split first when you want both sides to follow one another. Scient briefly marks a source-to-PDF destination so the matching place is easy to see. This needs a successful current build. If the PDF has no navigation index, it still opens and reads normally. Scient ships the small source-navigation helper itself, so this works the same way with TinyTeX, TeX Live, MiKTeX, or Tectonic and requires no extra package or PATH setup. If navigation cannot run, the status names the actual condition — for example a missing index, no mapping at that position, a timed-out query, or a damaged application helper — while leaving the PDF usable. The exactness comes from the compiler’s navigation index: some complex or RTL lines contain only a line-level location, so those lines can land near the typeset line instead of on the exact word.

The PDF keeps your place across rebuilds: your page, zoom, and scroll position stay put while a new version comes in, instead of snapping back to the top. If the PDF you’re looking at is older than the source it was built from, a stale badge tells you so.

Scient compiles with pdfLaTeX, driven through latexmk — or through Tectonic instead, if that’s what it finds. On the latexmk path, XeLaTeX and LuaLaTeX aren’t run: if a document asks for one, through a % !TEX program = xelatex (or lualatex) comment or by loading a package pdfLaTeX can’t process, such as fontspec or unicode-math, Scient detects that before the build starts and the error explains what the document needs instead of failing partway through a compile that was never going to work. Tectonic’s engine is XeTeX-based, so with Tectonic installed those same documents build normally and nothing is refused.

A document that loads fontspec only inside an engine test — the \usepackage{iftex} and \ifPDFTeX … \else … \fi pattern Pandoc’s default template writes — isn’t refused either. That document compiles fine under pdfLaTeX, because the branch loading those packages is never taken, so Scient lets the build run and answer for itself.

If Scient can’t find a LaTeX installation on your computer, it offers to install TinyTeX for you — a small distribution, about 70 MB, that lives with Scient and needs no administrator access. That install includes the packages most documents need, and anything still missing installs automatically the first time a document uses it; with your own TeX distribution, the error names the package to install. The first build of a document can therefore take a few minutes while those packages arrive — Scient says so, and names them, while it waits. Later builds of the same document are as fast as any other compile. Installing a package needs a network connection: when you’re offline, or when no package by that name can be found, the build stops and the error says which one it was. This one-click install is available on Windows (x64), macOS (Intel and Apple Silicon), and Linux (x64). On other architectures, install TeX Live, MiKTeX, or Tectonic yourself, and Scient will use it — an existing installation always keeps precedence over Scient’s own, on every platform. If you install one while a document is already open, select Rebuild: asking for a build by hand also makes Scient look for an engine again, so the one you just installed is picked up without reopening the file or restarting.

Compiling never leaves clutter in your files: build output, logs, and other compiler byproducts stay out of your project entirely.

For a project with multiple .tex files, add a comment near the top of a file that isn’t the main document:

% !TEX root = main.tex

Scient then compiles from main.tex whenever you edit or save that file, the same convention other LaTeX editors use.