A visual map of the CLI, local browser app, queue daemon, and loopback service.
Videx / overview
The problem
Many download tools force users to choose between approachable interfaces and powerful controls, while cloud-based workflows create unnecessary privacy concerns.
Local-firstno Videx download backend or user databasepublic evidence
One engineCLI and local browser app share queue servicespublic evidence
Videx / constraints
The constraints shaped the system
Media, credentials, queue history, and files must remain on the user’s machine.
The CLI and browser UI must share the same validated download plans.
A daemon crash must not lose or corrupt queued work.
Videx / decisions
The engineering decisions
01
SQLite as a process boundary
The queue persists plans, progress, output files, audit events, and cancellation requests across CLI and daemon processes.
A durable local queue gives the browser and CLI one source of truth without adding a hosted service.02
Loopback-only service
The companion binds to 127.0.0.1, validates Origin, uses a secure local session, and restricts output-file access.
The local network boundary is part of the product’s privacy model, not merely a deployment detail.03
Shared plans and safe recovery
Validated DownloadPlan objects are serialised into jobs, and running work is reclaimed after a daemon crash.
The queue owns recovery so a terminal closing does not make a user restart the whole workflow.
Videx / Architecture
Architecture
The public Vercel site is documentation only. The installed app starts a loopback service, while the CLI, browser interface, daemon, SQLite queue, yt-dlp, and FFmpeg remain on the user’s machine.
Shared validated plans between CLI and UI
Forward-only SQLite migrations
Output access limited to completed recorded jobs
Videx / Testing and release discipline
Testing and release discipline
Network extractors are mocked or served by local fixtures, so required tests never contact media websites. The project documents pytest, Ruff, mypy, and a coverage gate as part of the release workflow.
Videx / What I would improve next
What I would improve next
The next quality step is a moderated onboarding round with non-technical desktop users, focusing on installation, the local privacy boundary, and queue recovery language.
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