Open source · Self-hosted

Comments for
any application.

One API, one database, every app. Commently is a generic comments service — add threaded, context-anchored discussions to anything you build.

bash
# Post a comment from your app
$ curl -X POST http://localhost:3002/api/comments \
  -H "X-API-Key: $API_KEY" \
  -d '{"resource_id":"post-123","author_name":"Alice","body":"Great post!"}'
{"success":true,"data":{"id":"c9a2f...","body":"Great post!","created_at":"..."}}

Built for developers,
designed for scale.

Everything you need to add comments to your product — nothing you don't.

01

Multi-tenant

Each consuming app gets its own API key. Data is fully isolated between tenants. One Commently instance serves all your products.

02

Resource-agnostic

Comments attach to any opaque resource_id string. Commently never needs to know what a "deck", "post", or "lesson" is.

03

Context-anchored

Pin comments to sub-locations with context_key — a slide, paragraph, or code line. The convention is yours to define.

04

Threaded

One level of replies via parent_id. Clean, focused conversations without the chaos of deeply nested threads.

05

Stateless

No sessions, no WebSocket, no Redis. Pure HTTP + PostgreSQL. Scale horizontally by adding more instances behind a load balancer.

06

Your auth, your rules

Commently trusts your app to verify users. You pass author_id and decide who can comment on what. Zero lock-in.

How it works

Your app authenticates users. Commently authenticates your app. All state lives in PostgreSQL.

Your app
DeckDrop, Blog, Docs
Comments service
Commently API
Database
PostgreSQL
Authentication Your app sends X-API-Key on every request. Keys are hashed with SHA-256 — the raw key is shown once at creation.
Mapping resource_id = your entity's ID. context_key = sub-location. author_id = your user's identity.
Isolation Every query is scoped to the authenticated tenant. Tenant A can never read or mutate tenant B's data.

Self-hosted. Predictable cost.

Deploy on Render.com in minutes. No per-seat, per-comment, or per-API-call charges. Ever.

$14/mo
Everything included. No tiers, no limits.
  • Starter web service ($7/mo)
  • PostgreSQL Basic 256MB ($7/mo)
  • Unlimited tenants & comments
  • Auto-deploy from GitHub
  • Horizontal scaling when you need it
  • Your data, your server, your rules
Deploy now →

Add comments to your
app in 10 minutes.

Clone the repo, run the migration, start posting comments. It really is that simple.