Caddy vs Valkey

What Caddy is

Caddy is a web server that obtains and renews TLS certificates automatically, with a configuration file most people can read.

What Valkey is

Valkey is a BSD-licensed, vendor-neutral in-memory data structure server descended from Redis OSS 7.2.4. It supports RESP2/RESP3 clients, replication, Sentinel, Cluster, transactions, scripting, Pub/Sub, streams and configurable RDB or AOF persistence. Compatibility is strongest with Redis OSS 7.2 and earlier; Redis Community Edition 7.4+ data files are not compatible. Secure deployment is not automatic and requires network isolation, access control and, where needed, TLS.

What Valkey is built to do

Rich data structures

Stores strings, hashes, lists, sets, sorted sets, streams and specialized structures in memory.

Persistence choices

Supports periodic RDB snapshots, append-only logging, both together or no persistence.

Replication and failover

Uses asynchronous replication with Sentinel or Cluster deployment patterns.

RESP compatibility

Supports RESP2 and RESP3 and a documented migration path from Redis OSS through 7.2.

Choose Caddy if

• Anyone who wants a correctly configured HTTPS server without ceremony.

Choose Valkey if

• Caches, ephemeral state, rate limits, queues, streams and real-time application data
• Redis OSS 7.2-or-earlier migrations validated against the actual client, modules and persistence files
• Teams that can operate protected standalone, Sentinel or Cluster deployments

Skip Valkey if

• The system requires disk-first durability or zero acknowledged-write-loss guarantees
• A Redis CE 7.4+ data file must be opened directly without a supported migration route
• The service would be internet-exposed or deployed without firewall, ACL and recovery controls

Caddy: pros & cons

• HTTPS configured correctly by default
• Configuration is short and legible
• Single binary, easy to deploy
• Smaller community than nginx
• Fewer third-party guides
• Some advanced setups need plugins

Valkey: pros & cons

• Permissive open source: The server is community-developed under the BSD 3-Clause license.
• Familiar ecosystem: RESP clients and Redis OSS 7.2-era configurations, modules and data formats ease many migrations.
• Flexible roles: Data structures, expiry, scripting, transactions, Pub/Sub and streams cover cache and real-time patterns.
• Scale and availability options: Replication, Sentinel and Cluster support failover and sharding topologies.
• Compatibility has a boundary: Redis CE 7.4+ files are incompatible and future Valkey behavior can diverge.
• Unsafe defaults require hardening: Official guidance warns against direct internet exposure and calls for firewalling, binding, ACL/authentication and optional TLS.
• Durability is configurable: RDB, AOF and no-persistence modes have different data-loss, latency and recovery tradeoffs.
• Cluster consistency limits: Asynchronous replication allows windows of acknowledged-write loss, especially during minority partitions.