altcheck

Open-source alternatives, without the abandonware.

Directories tell you what alternatives exist. altcheck tells you which ones are still safe to bet on, checked live against GitHub with the reasons printed next to each verdict.

npx altcheck notion

Alternatives to notion: 3 VIABLE, 6 RISKY, 1 AVOID

VIABLE   AppFlowy-IO/AppFlowy             ★ 79k     AGPL-3.0        pushed 8d ago     bus 2
VIABLE   docmost/docmost                  ★ 22k     AGPL-3.0        pushed today      bus 1
         ↳ bus factor 1: one person wrote most of it
RISKY    outline/outline                  ★ 41k     BUSL-1.1        pushed today      bus 1
         ↳ source-available license (BUSL-1.1), not OSI open source
RISKY    hcengineering/platform           ★ 28k     EPL-2.0         pushed 1d ago     bus 3
         ↳ README says "no longer actively maintained"
RISKY    mattermost-community/focalboard  ★ 27k     multi:AGPL-3.0  pushed 6mo ago    bus 3
         ↳ no commits on the default branch in the last 12 weeks
...

(Excerpt of real output from 2026-11-11.)

Outline has 41k stars and is often listed as an open-source Notion alternative, but its license is BUSL. Huly (28k★) still gets commits, but its README says the repo is frozen and the hosted service has shut down. Stars and "last commit" show neither.

Use it

npx altcheck intercom              # alternatives + verdicts
npx altcheck vet hashicorp/terraform   # vet any single repo
npx altcheck zapier --json --limit 5   # for scripts

As an MCP server (Claude Code, Cursor, …)

claude mcp add altcheck -- npx -y altcheck --mcp

Tools: find_alternatives { tool } and vet_repo { repo }. Then ask: "We're about to buy Intercom. What's a viable open-source alternative?"

Related MCP server: gitlumen-mcp

What it checks

Candidates come from two places:

1. Seed: RunaCapital/awesome-oss-alternatives (MIT), 213 projects mapped to 134 proprietary tools.

2. Live: GitHub repos with 100+ stars whose description says they're an alternative to the tool. This catches the new AI-era projects the lists haven't added yet.

Rule: every verdict is computed live from public data. There's no sponsored ranking and no hand-written opinions.

Auth & limits

It uses GITHUB_TOKEN, GH_TOKEN or gh auth token if one is available. Each repo check costs about 5 requests. With a token (5,000 requests an hour) it checks 10 candidates by default. Without one, GitHub allows 60 an hour, so altcheck checks 5 candidates, which allows about 2 lookups an hour. It tells you when the limit resets.

How is this different from OpenSSF Scorecard / deps.dev?

Those score a repo you've already picked, mostly for security, and deps.dev reports Terraform (BUSL), Redis (AGPL-or-SSPL) and Chatwoot (open-core) all as non-standard. altcheck starts from the tool you want to replace, reads the license text to tell those cases apart, and gives a verdict with reasons that a person or an agent can act on.

Got a wrong result?

Open a "got this wrong" issue. It takes two minutes, and every report becomes a test case.

Honest limitations

• Bus factor is computed from the top 100 contributors' commit counts. It's a rough signal.

• "LICENSE changed" is often just a copyright-year bump. It's a prompt to look, not proof.

• Live search depends on how a repo describes itself. A project that calls itself "an open-source Notion alternative" gets in even if it's really something else.

• Which candidates make the cut is ordered, not ranked: live results (by stars) interleaved with the seed list. A good alternative can fall past --limit, so raise it if you're unsure.

• Stable, finished software (few commits because nothing needs changing) gets flagged as stale. Read the reason, not just the label.

• License-text detection reads the first 4 KB of the LICENSE file. A license explained only in a README or in per-file headers can be missed.

• Measured on two blind benchmarks (60 repos and 40 tools in total, each never used for tuning and scored once; see bench/):

  • status 59/60;

  • exact license class 48/60, with every miss cautious: 0 cases of VIABLE for a non-OSS or abandoned repo;

  • search precision about 84%, then about 89% after one round of fixes.

• Ambiguous brand names are noisy: "github" also matches Copilot and github.com URLs; "framer" matches Framer Motion.

• Big projects that don't call themselves "an alternative to X" (Immich, Bitwarden, Mattermost) only appear if the seed list has them.

• Projects not hosted on GitHub (GIMP, Krita, Inkscape) are invisible.

• The MCP server is tested with the official MCP TypeScript SDK client over stdio, but not yet inside the Claude Code or Cursor apps.

Development

npm test             # node:test, no network
npm run build:seed   # regenerate data/seed.json from scripts/runa-README.snapshot.md

Zero runtime dependencies. Node 18 or newer. MIT.