backend-realtime SKILL.md skillA

This file is byte-identical to the first copy the registry indexed. Same content hash, so the same checks give both the same grade.

backend-realtime from kensaurus/skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.

Install it, pinned
mdr add kensaurus/skills/backend-realtime@git:20261006.39320f8

Pins git:20261006.39320f8 in mdr.lock. Pin the fingerprint instead.

Audit grade
A, 17 of 17 checks passed
Kind
SKILL.md skill
Repository
kensaurus/skills
Path
skills/backend-realtime/SKILL.md
Versions recorded
5
Latest version
git:20261006.39320f8, committed Oct 6, 2026
First version recorded
Aug 21, 2026
Size
6,838 bytes
Repository stars
9
License
MIT

Implement real-time features with WebSockets, Supabase Realtime, or Server-Sent Events. Use when "real-time", "live updates", "WebSocket", "notifications", "chat", "presence", "collaborative", "live data", or "instant sync".

Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.

What the file says

# Real-time Features Skill

**Degree of freedom: MIXED.** Which transport and event `[HIGH freedom]`;
existing-subscription probes and unmount cleanup `[LOW freedom — run exactly]`.

## How to reason

1. **Observe** — existing channels, sockets, hooks, cleanup
2. **Interpret** — new subscription vs reuse vs transport mismatch
3. **Classify** — postgres-changes / presence / broadcast / SSE / optimistic
4. **Severity** — leaked or duplicate subscription outranks a missing typing indicator

## Worked example

> **Observe:** chat mounts `useRealtimeMessages` twice; no untrack on leave; `package.json` already has `@supabase/supabase-js`.
> **Interpret:** duplicate INSERT listeners; leftover presence.
> **Classify:** one channel hook with unmount cleanup; reuse Supabase Realtime — do not add Socket.io.
> **Verify:** one `postgres_changes` subscription; `removeChannel` on unmount; no second socket lib.

## Self-critique before reporting

- **Existing first** — grepped channels/sockets before adding a library
- **Cleanup** — every subscribe has unmount `removeChannel` / `close`
- **One listener** — no duplicate subscription for the same event
…

Read the whole file at its exact version.

How to install

The exact contents, by fingerprint
mdr add kensaurus/skills/backend-realtime@sha256:bd0b829a45ce516b

The line at the top of this page pins the label git:20261006.39320f8, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.

Badge

mdr badge

[![mdr](https://markdownregistry.com/badge/art_jsxphdhxpecfbsyl.svg)](https://markdownregistry.com/a/art_jsxphdhxpecfbsyl)

2 badge image fetches in 30 days. What the badge shows.

Versions

The registry has recorded 5 versions of this file, between Aug 21, 2026 and Oct 6, 2026, about one every 12 days. Its first recorded version is graded B and its latest A.

versioncommittedcommitsizeaudit
git:20261006.39320f8 latest2026-10-06 39320f8 6,838 BA view · diff
git:20260923.68c095e2026-09-23 68c095e 10,136 BA view · diff
git:20260923.cf348bd2026-09-23 cf348bd 10,085 BB view · diff
git:20260912.33d48b12026-09-12 33d48b1 10,005 BB view · diff
git:20260821.2a410312026-08-21 2a41031 10,015 BB view

Audit of the latest version

A  17 of 17 checks passed. Fixed automatic checks with no AI involved, so the same checks give the same answer every run.
  • pass: Frontmatter block present
  • pass: Frontmatter declares a name
  • pass: Frontmatter declares a description
  • pass: Size between 200 bytes and 200 KB (6838 bytes)
  • pass: No zero-width or bidi control characters
  • pass: No instruction hidden inside an HTML comment
  • pass: No link to an exfiltration or paste host
  • pass: No credential-shaped string
  • pass: No instruction to send local credentials anywhere
  • pass: No text hidden with inline styles
  • pass: No prompt-injection phrasing
  • pass: No curl or wget piped into a shell
  • pass: No recursive delete of root, home or parent
  • pass: No instruction to read or print local credentials
  • pass: No base64 blob over 200 characters
  • pass: No link to a raw IP address
  • pass: No script tag

Source

GitHub

kensaurus/skills · 9 stars · license MIT · pushed 2026-10-19 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_jsxphdhxpecfbsyl
GET https://markdownregistry.com/api/v1/resolve?ref=kensaurus/skills/backend-realtime
GET https://markdownregistry.com/api/v1/blob/bd0b829a45ce516b22164b79e511b2238083592b63946b94e31661969ed8e504

Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.

Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.

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Every file in kensaurus/skills

Other files named backend-realtime

backend-realtime SKILL.md skill
kensaurus/cursor-kenji · skills/backend-realtime/SKILL.md · Implement real-time features with WebSockets, Supabase Realtime, or Server-Sent Events. Use when "real-time", "live…
git:20261006.39320f8 · audit A · 9 stars

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