langtechdepot

Setting up a machine? Don't read this page. Go to https://depot.langtech.cloud/ — pictures, four steps, no jargon. This README is for the people who maintain the thing.

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Language workers go where the internet is poor, expensive or absent, and they need the current installers already on the machine when they get there. This is the layer that puts them there: a distribution front end for the LangTechDepot software repository, built on Syncthing (open source, no licenses, actively developed). Replaces Resilio Sync, whose licences can no longer be obtained.

intent.md states the goals this has to serve, how far the code gets today, and what that rules out. Read it before changing anything a user touches.

How it works: the repository server in California marks every catalog folder Send Only and offers all of them to each registered device. The installer subscribes to All_Contents_List, whose LangTechDepotFiles.txt lists every folder with its size and a description, and shows that list as checkboxes; unticked folders are ignored. Accepted folders stay current automatically, and devices holding the same folders sync from each other, so machines on one office LAN pull from their neighbour instead of from California — the old btsync swarm, without the licensing.

Folders are receive-only on the client: local edits and deletions are flagged and revertible, and nothing local propagates outward.

The four-step journey

A field user stays on depot.langtech.cloud throughout, but two programs answer there, designed as one flow rather than two projects:

Step	What the user does	Where it happens
1	Fills the form, gets a token	/signup — server/register.py
2	Downloads the installer	/ — the instructions site, docs/
3	Runs it, pastes the token	the installer — client/
4	Ticks the folders they want	the installer's folder list

The token page hands back to the platform page the user came from (the ?os= parameter rides through the form), and the step rail, palette and components are the same on both sites. Keep it that way: the seam is the part users notice.

The token goes over HTTPS to the registration service and never touches Syncthing's configuration, because Syncthing broadcasts device names to every peer in the cluster — a token embedded in one would be visible to every other field user.

The instructions site

docs/ is plain HTML with one stylesheet and one small script. No build step, no framework, no web fonts, no bitmap images: the audience is on slow links and the illustrations are inline SVG.

.github/workflows/pages.yml publishes it on every push to main, building the Windows installer and packing it into downloads/langtechdepot-windows.zip on the way, so the site can offer a single file to download that browsers and mail filters let through (a bare .bat gets questioned). The .bat is built rather than committed — a committed copy is a second copy of the installer, and the second copy is the one that goes stale. The workflow also fails, publishing nothing, if any page links to a download it did not build. One-time setting: Settings → Pages → Source → GitHub Actions.

To look at it locally:

python3 -m http.server -d docs 8899     # then open http://127.0.0.1:8899/

The download buttons 404 in that preview; the workflow is what fills downloads/.

Editing it

Every link inside the site is relative and the one absolute URL — the curl command on the Linux page — rewrites itself from window.location, so the whole tree can be served from anywhere without edits. DEPOT and SIGNUP at the top of docs/assets/site.js are the only two things that name the registration server.

The site links to the sign-up form at /signup, not to a token page: a user cannot be sent straight to a token, because filling that form in is what produces one. register.py also answers / with the same form, but on depot.langtech.cloud Caddy gives / to the instructions site.

Two things bite when hand-writing the SVG:

• Quote every attribute value. stroke-width=2/> parses as stroke-width="2/" and the tag never closes, so every shape after it becomes an invisible child of the first one. The page looks blank and nothing errors.
• register.py carries its own copy of the CSS and the copy-button script. It is a single stdlib file that must render correctly when the other site is unreachable, so the duplication is deliberate. Change one, change both.

Install (what the site tells people)

Windows — download langtechdepot-windows.zip, open it, double-click setup-langtechdepot.bat. No extracting needed: the .bat is self-contained, and Explorer runs it from a temporary copy (so the zip window should stay open until it finishes). It installs Syncthing through winget (--scope user, so no admin rights); on a machine without winget, the zip is extracted and syncthing.exe put beside the .bat by hand. Either way it is copied to %LOCALAPPDATA%\Programs\Syncthing\, the fixed path the startup shortcut uses. Nothing here ever downloads the executable itself — antivirus dropper heuristics flag scripts that fetch a binary and then register it for startup.

The .bat exists because a stock Windows machine refuses to run a downloaded .ps1 at all: right-clicking the script and choosing Run with PowerShell fails, and the window closes before the reason is readable. So the one file carries setup-langtechdepot.ps1 inside itself below a marker line. At run time it extracts that part to a temporary .ps1, runs it with -From set to the .bat's own folder (where a hand-placed syncthing.exe is looked for), deletes it, and waits for a key before closing, so anything that goes wrong stays on screen.

Edit only client/setup-langtechdepot.ps1. The .bat is built from client/setup-langtechdepot.bat.in (the launcher, ending at the marker line) plus the .ps1, by client/build-bat.sh — run it locally to get a .bat to test on Windows; the workflow runs the same script when it publishes. The built .bat is gitignored.

For anyone who prefers the command line: on Windows the installer also installs itself as modify-langtechdepot.bat, on the user's PATH, so that these commands are available in any new Command Prompt:

modify-langtechdepot list 
modify-langtechdepot add <FolderID>...
modify-langtechdepot ignore <FolderID>...

(with no arguments it is the installer again, dialog and all).

Linux

bash client/install-langtechdepot.sh

No admin rights on either platform. The installer sets Syncthing to start automatically, registers the machine, and shows the folder list. Syncthing's own page is usually at http://localhost:8384; the installer prints the actual address, since the port moves if something else holds it. Files land under ~/LangTechDepot/Assets/ (or %USERPROFILE%\LangTechDepot\Assets\, or wherever the user pointed it; Assets is then a link or shortcut to there). On both, the installer keeps itself as modify-langtechdepot, which the "Change my Assets" item in the LangTechDepot folder runs.

On Linux, langtechdepot-subscribe.sh lists the catalog and subscribes by folder ID (langtechdepot-subscribe.sh <id>...), taking a folder back off the ignore list if need be; langtechdepot-subscribe.sh ignore <id>... ignores one, like modify-langtechdepot ignore on Windows.

Sneakernet

Any synced machine holds a complete plain-files mirror of the folders it subscribes to — copy the tree to a thumbdrive and carry it. For repeatable offline updates, install Syncthing portably on the drive itself and let it sync as its own device whenever the drive visits a connected machine.

Server

See server/SETUP.md — Syncthing standup, the folder catalog, and the registration service (server/register.py) that serves the form, issues single-use tokens, admits devices, and keeps the catalog shared — and guards it: a change from any device but the server is undone and that device cut off. Administration is register.py admin list|approve|revoke|restore.

server/Caddyfile.example puts everything on depot.langtech.cloud: the instructions site at / (mirrored from GitHub Pages, so nothing is deployed to the box for it), the form at /signup, and the Groups tree at /files. sillsdev.github.io/langtechdepot stays up as a second copy.

python3 server/test_register.py     # full suite; no network, no real Syncthing

Repo layout

docs/    index.html                  the instructions site: which computer?
         windows.html · linux.html   four steps, with pictures
         help.html                   what normally goes wrong
         assets/site.css · site.js   shared with register.py's pages
client/  setup-langtechdepot.ps1     field installer (Windows) - edit this
         setup-langtechdepot.bat.in  launcher that the .ps1 is wrapped in
         build-bat.sh                builds setup-langtechdepot.bat from those two
         version.sh                  the version number, from the latest v* git tag
         START-HERE.txt              rides along in the Windows zip
         install-langtechdepot.sh    field installer (Linux)
         langtechdepot-subscribe.sh  CLI catalog list / subscribe (Linux; Windows
                                     uses modify-langtechdepot, i.e. the installer)
server/  SETUP.md                    server standup guide
         register.py                 registration service + admin CLI
         test_register.py            end-to-end test against a stub Syncthing
         ltd-sync-admin              sudo wrapper for `register.py admin`
         token_backup.sh             nightly sqlite .backup, 30-day retention
         langtechdepot-register.service   systemd unit
         register.env.example        configuration template
         Caddyfile.example           TLS front end: site, form and /files on one name
images/                              screenshots for intent.md