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Open-Source DevOps · ridafkih

keeper.sh

Keeper.sh is an open-source calendar aggregation and sync tool that pulls events from multiple calendar sources (Google, Outlook, iCloud, CalDAV, ICS) and synchronizes them across destinations. It also functions as an MCP (Model Context Protocol) server for AI agent integration and is designed to be self-hosted or used via a paid cloud tier.

Source: GitHub — github.com/ridafkih/keeper.sh
1.2k
GitHub stars
38
Forks
TypeScript
Primary language
AGPL-3.0
License (OSI-approved)

Key facts

Objective fields from the source. Values we can't verify are shown as “Unknown” rather than guessed.

FieldValue
Repositoryridafkih/keeper.sh
Ownerridafkih
Primary languageTypeScript
LicenseAGPL-3.0 — OSI-approved
Stars1.2k
Forks38
Open issues82
Latest releasev2.12.0 (2026-06-30)
Last updated2026-07-06
Sourcehttps://github.com/ridafkih/keeper.sh

What keeper.sh is

TypeScript/Bun-based service with a React web frontend, PostgreSQL backend, Redis queue, and microservice architecture (API, web, MCP, cron, worker). Uses event UID mapping and metadata flags to track synced events across providers and detect stale or orphaned calendar entries for cleanup.

Quickstart

Get the keeper.sh source

Clone the repository and explore it locally.

terminalbash
git clone https://github.com/ridafkih/keeper.sh.gitcd keeper.sh# follow the project's README for install & configuration

Need it deployed, integrated, or customized instead? DEV.co ships production installs.

Best use cases

Multi-calendar conflict prevention

Keep business, personal, and work calendars in sync to prevent double-booking and scheduling conflicts across separate calendar providers.

Aggregate event feeds for AI assistants

Use the MCP server to give Claude or other AI agents unified access to calendar data across multiple sources for scheduling and availability queries.

Self-hosted calendar gateway with data control

Organizations needing on-premise calendar sync without reliance on third-party services can deploy Keeper.sh to maintain data governance and autonomy.

Implementation considerations

  • AGPL-3.0 license requires legal review for commercial or network-service use; modifying or hosting for others triggers copyleft obligations.
  • Self-hosting mandates Bun v1.3.11+, Docker, Docker Compose, PostgreSQL, Redis, and TLS certificate management (Caddy reverse proxy included).
  • Event sync logic relies on UID-based mapping and provider-specific metadata (suffix `@keeper.sh` or category flags); non-standard calendar fields may require custom logic.
  • Free tier limited to 2 sources and 1 destination; production use typically requires $0 self-hosted or $5/month cloud Pro plan.
  • 82 open issues indicate active development; latest release v2.12.0 dated 2026-06-30 with final push 2026-07-06 (stable but monitor for breaking changes).

When to avoid it — and what to weigh

  • Proprietary software requirements — AGPL-3.0 licensing requires any modifications or network service use to release source code; not suitable for closed-source derivative work without review.
  • Minimal operational overhead — Self-hosted deployment requires PostgreSQL, Redis, Docker Compose, and active infrastructure management; cloud tier available but adds subscription cost.
  • Enterprise SLA/support expectations — Single-maintainer open-source project with 82 open issues and no stated SLA, incident response, or commercial support team.
  • Calendar-agnostic real-time event capture — Free tier syncs every 30 minutes; Pro (self-hosted or cloud) syncs at 1-minute intervals. Real-time webhooks or sub-minute cadence unknown.

License & commercial use

AGPL-3.0 (GNU Affero General Public License v3.0). Requires source disclosure if modified or deployed as a network service. Use for internal, unmodified deployments is generally permissible; commercial or SaaS use, or derivative products, require legal review.

AGPL-3.0 imposes copyleft obligations on network services and modifications. Internal deployment and use (self-hosted, unmodified) likely permissible, but commercial resale, SaaS offerings, or closed-source integrations require attorney review. Cloud-hosted tier (keeper.sh) offered by maintainer as a compliant commercial option.

DEV.co evaluation signals

Editorial assessment — not user reviews. Directional, with an explicit confidence level.

SignalAssessment
MaintenanceActive
DocumentationAdequate
License clarityClear
Deployment complexityHigh
DEV.co fitGood
Assessment confidenceHigh
Security considerations

Project handles OAuth credentials, calendar API tokens, and event data from multiple providers. No explicit security audit, penetration test, or vulnerability disclosure policy stated in provided data. AGPL source availability aids peer review but does not guarantee secure implementation. Self-hosted deployments inherit responsibility for PostgreSQL, Redis, and network security. TLS via Caddy in dev environment; production TLS configuration depends on deployment method.

Alternatives to consider

Zapier/IFTTT

Managed, no-code calendar automation with no infrastructure overhead; lacks fine-grained event sync control and MCP/AI integration.

CalDAV server (e.g., Nextcloud, Radicale)

Open-source, self-hosted calendar server; focuses on unified CalDAV endpoint rather than cross-provider aggregation and sync.

Google Calendar delegation + manual sync

Built-in, zero-cost; limited to Google ecosystem and no automation; does not solve multi-provider or AI agent access.

Software development agency

Build on keeper.sh with DEV.co software developers

Assess feasibility by reviewing AGPL-3.0 compliance, estimating self-hosted infrastructure, and testing multi-provider sync in a staging environment. Contact Devco for enterprise deployment guidance.

Talk to DEV.co

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keeper.sh FAQ

Can I use Keeper.sh commercially without legal review?
AGPL-3.0 requires source disclosure for network services and modifications. Internal, unmodified deployments are likely permissible; commercial SaaS or closed-source derivatives require attorney review. Cloud-hosted tier (keeper.sh) is a compliant commercial option.
What is the minimum self-hosted infrastructure?
Bun v1.3.11+, Docker, Docker Compose, PostgreSQL 13+, Redis, and TLS certificate (Caddy included). Typical stack is ~500MB-2GB RAM for small deployments; scalability depends on event volume and source count.
How are calendar events tracked across syncs?
Events are flagged with `@keeper.sh` UID suffix or category metadata. If a source event is deleted, the corresponding destination event is removed. Stale local events with no source mapping are auto-purged.
Does Keeper.sh support real-time sync?
Free tier: 30-minute intervals. Pro (cloud or self-hosted): 1-minute intervals. Sub-minute or webhook-driven sync is not documented.

Software development & web development with DEV.co

From first prototype to production, DEV.co delivers software development services around tools like keeper.sh. Our software development agency staffs experienced software developers and web developers for custom software development, web development, integrations, and ongoing support across open-source devops and beyond.

Evaluate Keeper.sh for Your Calendar Stack

Assess feasibility by reviewing AGPL-3.0 compliance, estimating self-hosted infrastructure, and testing multi-provider sync in a staging environment. Contact Devco for enterprise deployment guidance.