session-storage-memcache Overview

The remix/session-storage-memcache package stores session data in Memcache (Memcached), a distributed in-memory caching system. Like Redis, Memcache stores data in memory for fast access and supports automatic expiration, making it suitable for session storage in multi-server deployments.

Key Concepts

• Memcache (Memcached) -- A distributed in-memory key-value cache. It runs as one or more server processes and is accessed over the network. When you have multiple Memcache servers, keys are distributed across them using consistent hashing.
• TTL (Time-to-Live) -- How long a session entry stays in Memcache before it is evicted. Active sessions have their TTL refreshed on every request.
• Key prefix -- A string prepended to every session key (e.g. session:abc123). Useful for namespacing when sharing a Memcache instance.

Memcache vs Redis

Both are valid choices for production session storage. Here is how they differ:

Concern	Memcache	Redis
Data model	Simple key-value only	Rich data types (strings, hashes, lists, sets)
Persistence	No disk persistence	Optional disk persistence
Clustering	Built-in via consistent hashing	Requires Redis Cluster or Sentinel
Memory management	LRU eviction when memory is full	Configurable eviction policies
Best for	Pure caching, simple session storage	Sessions + other use cases (queues, pub/sub)

Choose Memcache if you already use it in your infrastructure or prefer its simplicity. Choose Redis if you want disk persistence or plan to use the same store for other purposes.

Quick Example

// app/session.ts
import { createCookie } from 'remix/cookie'
import { createMemcacheSessionStorage } from 'remix/session-storage-memcache'

let sessionCookie = createCookie('__session', {
  httpOnly: true,
  secure: process.env.NODE_ENV === 'production',
  sameSite: 'Lax',
  secrets: [process.env.SESSION_SECRET!],
  maxAge: 60 * 60 * 24 * 7, // 1 week
})

let sessionStorage = createMemcacheSessionStorage({
  servers: [process.env.MEMCACHE_URL!],  // e.g. 'localhost:11211'
  ttl: 60 * 60 * 24 * 7,                 // Match cookie maxAge
  prefix: 'session:',
})

// app/server.ts
import { createRouter } from 'remix/fetch-router'
import { session } from 'remix/session-middleware'

let router = createRouter({
  middleware: [
    session(sessionCookie, sessionStorage),
  ],
})

Handlers use context.get(Session) exactly the same way as with any other storage backend.

Configuration Options

Option	Type	Default	Description
servers	string[]	--	Memcache server addresses. Required if client is not provided.
client	MemcacheClient	--	An existing Memcache client. Required if servers is not provided.
ttl	number	604800 (7 days)	Session lifetime in seconds. Refreshed on every request.
prefix	string	'session:'	Key prefix for session entries.

Next Steps

• Tutorial: Set Up Memcache Session Storage -- Step-by-step setup.
• API Reference -- Full documentation of createMemcacheSessionStorage.