TeXbrain puts pdfTeX and Git in a free local-first browser editor

Why it matters

TeXbrain shows how WebAssembly can move a traditionally server-heavy developer workflow onto the user's device, while exposing the compatibility costs that local-first software still carries.

Braian Plaku used an August 25th announcement to put TeXbrain, his free browser-based LaTeX editor, in front of developers nearly five months after an earlier public launch post. The editor compiles PDFs locally and includes Git controls.

The MIT-licensed project moves the writing interface, pdfTeX compiler and Git client into the browser. Users can open a local folder, edit a multi-file project, preview the PDF, create branches and push changes without installing a TeX distribution or creating a TeXbrain account.

That combination comes directly from Plaku's experience writing a thesis. He says he "spent more time fighting tooling than actually writing", caught between local LaTeX installations that behaved differently across computers and online editors that charged for Git integration. His answer was an editor that treats the browser as the application runtime rather than a window into a remote compilation service.

A thesis tool built from frustration

Plaku is a software developer at Julius Blum GmbH in Vorarlberg, Austria, where his personal site says he works on computer vision, machine learning and 6D pose estimation. He holds a BSc in electrical engineering, and his public profiles list him as completing a computer science degree at FH Vorarlberg and an artificial intelligence master's degree at Johannes Kepler University Linz.

His work before TeXbrain ranged from machine-learning experiments to a mobile app, a browser game and an indoor climate monitor. In March 2025, FH Vorarlberg reported that Plaku and three teammates won a TU Wien hackathon by generating synthetic energy-consumption data designed to preserve privacy.

TeXbrain applies a similar instinct to technical writing: keep sensitive material close to the user and remove infrastructure where possible. The live editor requires no login. TeXbrain's README says files remain on the user's machine unless they are explicitly pushed to a remote repository.

Plaku's pitch is deliberately narrower than building another full academic collaboration company. He is packaging the parts of a LaTeX workflow that caused him trouble, then publishing the result as open-source software.

The browser does the compiling

According to the project's repository documentation, TeXbrain uses the SwiftLaTeX WebAssembly port of pdfTeX. Before each compilation, project files are written to an in-memory filesystem. The browser produces the PDF locally and renders it with Mozilla's pdf.js.

The repository identifies SvelteKit and CodeMirror 6 as the main application and editing components. Its documentation says Git operations run through isomorphic-git, with repository data stored using LightningFS and IndexedDB. TeXbrain provides browser controls for cloning repositories, staging files, committing, branching, pulling, merging and pushing.

Plaku has also added local-folder access through the File System Access API. The repository documentation says that feature works fully in Chromium-based browsers, including Chrome and Edge. Firefox and Safari users receive a virtual filesystem instead, preventing direct reads and writes to project folders on disk through the same interface.

The product page advertises account-free peer-to-peer collaboration. TeXbrain's package manifest lists Yjs, y-codemirror.next and y-webrtc, the components used for collaborative editing and peer synchronization.

The local-first description needs one qualification. TeXbrain downloads missing packages from TeX Live mirrors and caches them, while Git clone, pull and push operations use a CORS proxy. The README says compilation can continue without a network connection when a project's required packages have already been cached. A document that calls a package the browser has never downloaded still needs a connection for the first retrieval.

The missing parts are the hard parts

TeXbrain's repository documentation is unusually direct about the current limitations. The editor supports pdfTeX, leaving out XeTeX and LuaTeX. Documents that depend on packages such as fontspec or polyglossia will not compile.

Native BibTeX and Biber workflows are also missing. For biblatex documents, the repository says TeXbrain converts references into a plain thebibliography and ignores the selected citation style. Conventional BibTeX projects need to include a pre-generated .bbl file. Package availability is tied broadly to the TeX Live 2020 era, putting some newer document classes and package releases outside its reach.

Those constraints separate a useful personal tool from a complete substitute for mature hosted platforms. Overleaf offers visual editing, comments, project history, bibliography integrations and a large template catalog, with several collaboration and integration features reserved for paid plans. Its Git and GitHub integrations are premium features, the exact paywall Plaku set out to remove.

TeXbrain also enters a growing group of client-side typesetting projects. TeXlyre, an open-source, local-first browser editor for LaTeX and Typst, offers peer-to-peer collaboration. NLnet began funding TeXlyre in March 2026 to modernize its compilation infrastructure and support contemporary packages. Thetapad similarly uses SwiftLaTeX for browser compilation while pairing a free tier with paid options.

Plaku is competing through simplicity and control. TeXbrain does not need to match every hosted feature to become useful for students and researchers who already keep projects in Git, want a live preview and would rather avoid uploading unpublished work to another service.

A working project, without startup theater

As of August 25th, the TeXbrain repository showed approximately 42 stars and six forks. Those figures establish a modest open-source footprint, rather than a user count or evidence of commercial traction.

The more important evidence is in what Plaku has shipped. TeXbrain joins the compiler, editor, filesystem and version-control client inside a static web application deployed through GitHub Pages. It exposes the compromises in its own documentation and gives users the source code required to inspect or change them.

Broader LaTeX engine support, current packages and complete bibliography tooling will determine how far TeXbrain can move beyond straightforward projects. The present release already delivers the workflow Plaku wanted during his thesis: open a tab, write, compile and push, with no subscription standing between the document and its Git history.