PlanetScale vs Valkey

What PlanetScale is

PlanetScale is a managed MySQL platform whose distinguishing feature is database branching: you branch a schema like code, open a deploy request, and merge it without locking tables. Schema changes stop being the scary part of a release: a branch is reviewed and merged without locking the table. The trade-off is that foreign key behaviour and some MySQL features work differently under its sharding model, which has to be designed for.

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 PlanetScale is built to do

Database branching

Branches a schema like code and merges it through a deploy request.

Non-blocking schema changes

Applies migrations without locking tables in production.

Managed MySQL

Runs MySQL-compatible clusters without server administration.

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 PlanetScale if

• Teams that want managed Postgres or Vitess MySQL with 3-node high availability from $15/month
• Dev and staging databases on single-node Postgres from $5/month
• Workloads that need local NVMe performance: Metal Postgres from $50/month with 10 GiB

Skip PlanetScale if

• You expect a free tier — none is listed on the pricing page
• You run Vitess Metal for a small app: it starts at $609/month
• Your cloud region is not us-east-1; prices vary by provider and region

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

PlanetScale: pros & cons

• Schema changes without downtime
• Branching workflow that mirrors Git
• Managed, with no server maintenance
• No foreign key constraints in the traditional sense
• Costs rise quickly beyond small workloads
• Ties you to their platform and workflow

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.