Anchor
What it is
Anchor is free classroom software for schools using managed or bring-your-own-device Windows laptops. A teacher starts a focus session from a web dashboard, selects a class, and sets an allowlist of apps and websites. Student Windows devices enforce that list while the dashboard shows student states and events live. Teachers can adjust allowed bundles, review activity, and end enforcement. Microsoft 365, Smartschool, and GeoGebra are named selectable bundles, with sign-in through existing school Microsoft accounts. Off-list apps are set aside rather than closed, while blocked Edge pages offer a request-access option. Anchor observes only during an active teacher-started session and does not record allowlisted work, keystrokes, page contents, screenshots, passwords, or browsing outside sessions. Each school runs a single-tenant backend in its Azure subscription. The project is GPL-3.0 licensed, self-hostable, and publicly auditable. Student support is limited to Windows 10 version 1809 or later, Windows 11, and Microsoft Edge.
For and against
For
- Free with no licence or per-seat charge
- Live dashboard shows student states and events
- Teachers can adjust allowlists during sessions
- Self-hosted and publicly auditable
- Does not record activity outside sessions
Against
- No student agent for Mac or Chromebook
- No support for iPad or phone students
- Soft enforcement can be bypassed
- Azure hosting costs may apply
The verdict
Anchor focuses on session-based app and website control while limiting what classroom activity it records. Its Windows-only scope, self-hosted Azure setup, and deliberately soft enforcement are central selection considerations.
Who it suits
It suits schools and teachers supervising Windows classroom laptops through a self-hosted web dashboard. It is not intended for student Macs, Chromebooks, iPads, phones, or other browsers.
Plans and prices
Anchor software
self-hosted · Windows/Edge student client · school supplies Azure backend
Read 15 Oct 2026 · plinklabs.org
Azure hosting estimate
about 1,000 students · Basic B1 App Service · SQL Standard S0 · free-tier Static Web App
Read 15 Oct 2026 · plinklabs.org
Azure hosting estimate with larger database
about 1,000 students · Basic B1 App Service · SQL Standard S1 · free-tier Static Web App
Read 15 Oct 2026 · plinklabs.org
Anchor
Self-hosted backend · single school per deployment · Azure hosting costs may apply
Read 4 Oct 2026 · plinklabs.org
On the record
- Agent stack
- The student client is a WinUI 3 and C# application using Velopack for updates.github.com · read 15 Oct 2026
- Allowlist bundles
- Teachers choose named bundles such as Microsoft 365, Smartschool and GeoGebra instead of entering raw domains.plinklabs.org · read 15 Oct 2026
- API architecture
- The repository describes an ASP.NET Core REST API with Entity Framework Core, SignalR and Microsoft Entra authentication.github.com · read 15 Oct 2026
- App enforcement
- The Windows agent moves off-allowlist applications into the background and displays a gentle overlay without closing the applications.plinklabs.org · read 15 Oct 2026
- Audience
- The maker describes Anchor as classroom software made by teachers for schools using managed or bring-your-own-device Windows laptops.plinklabs.org · read 4 Oct 2026
- Authentication
- The deployment creates single-tenant Microsoft Entra registrations for the API and dashboard, with school accounts used instead of separate Anchor passwords.plinklabs.org · read 15 Oct 2026
- Class management
- Classes can be created manually, imported from CSV or populated from a school directory and reused for later sessions.plinklabs.org · read 15 Oct 2026
- Dashboard stack
- The teacher dashboard is implemented as Flutter Web with MSAL.js and is intended for Azure Static Web Apps.github.com · read 15 Oct 2026
- Data collection
- During an active session the system can send off-list URL details, unblock requests, integrity signals and liveness heartbeats; it does not record keystrokes, screenshots, passwords or allowlisted browsing.plinklabs.org · read 15 Oct 2026
- Deployment defect
- A GitHub issue documented backend deployment failures caused by a missing Azure publish-profile secret in the CI workflow.github.com · read 15 Oct 2026
- Developer prerequisites
- Local development documentation lists .NET 10 SDK, Node.js LTS, Flutter, Azure CLI and a controllable Entra tenant as prerequisites for the relevant components.github.com · read 15 Oct 2026
- Documented defect
- A GitHub issue reported that the foreground watcher failed to deliver Windows foreground callbacks, allowing off-list applications to remain usable during real sessions.github.com · read 15 Oct 2026
- Extension stack
- The browser component is a TypeScript Edge Chromium Manifest V3 extension.github.com · read 15 Oct 2026
- Hosting
- Each school runs a single-tenant backend in its own Azure subscription, and student devices and the dashboard communicate only with that backend.plinklabs.org · read 4 Oct 2026
- Installation
- The student agent is a per-user Setup.exe that needs no administrator rights, starts at Windows sign-in and updates itself; Edge receives the extension through policy.plinklabs.org · read 15 Oct 2026
- Integrations
- The teacher page names Microsoft 365, Smartschool, and GeoGebra as selectable bundles; sign-in uses existing school Microsoft accounts.plinklabs.org · read 4 Oct 2026
- Integrity witness
- A native-messaging witness lets the agent and extension report if the other component is disabled during a session.plinklabs.org · read 15 Oct 2026
- Licence
- Anchor is released under the GPL-3.0 licence and is self-hostable.plinklabs.org · read 15 Oct 2026
