whichdb
vs

Amazon Keyspaces vs ScyllaDB

Amazon Keyspaces: Serverless, CQL-compatible Cassandra service on AWS with no clusters to manage. ScyllaDB: C++ rewrite of Cassandra with shard-per-core design; also speaks the DynamoDB API.

key differences

  • Licensing: Amazon Keyspaces is proprietary (Proprietary (AWS service)); ScyllaDB is source-available (ScyllaDB Software License Agreement 1.1).
  • ScyllaDB is built for larger datasets (Multi-PB) than Amazon Keyspaces (≤ 1 PB).
  • Only Amazon Keyspaces has transactions, time travel.
  • Only ScyllaDB has secondary indexes, json, materialized views, compression, online schema changes.
  • Amazon Keyspaces has a serverless option; ScyllaDB does not.

choose amazon-keyspaces for

  • +Moving existing Cassandra apps to AWS without ops
  • +Spiky workloads that suit on-demand pricing
  • +Serverless apps that need a CQL data model
  • +Industrial and IoT device data

best at · OLTP, IoT, Time-series

choose scylladb for

  • +Chat and messaging history at very high volume
  • +Low-latency feature stores for ML
  • +Cassandra or DynamoDB migration targets
  • +IoT and telemetry ingestion

best at · OLTP, Time-series, IoT

Amazon KeyspacesServerless, CQL-compatible Cassandra service on AWS with no clusters to manage.
ScyllaDBC++ rewrite of Cassandra with shard-per-core design; also speaks the DynamoDB API.
overview
Primary model
Wide-Column
Wide-Column
Also supports
Key-Value
Key-Value
Type
Managed service
Database engine
Status
Active
Active
Developer
Amazon Web Services
ScyllaDB Inc.
First release
2020
2015
Latest version
–
2026.3.4 (Oct 2026)
License
ProprietaryProprietary (AWS service)
Source-availableScyllaDB Software License Agreement 1.1
Free tier
✓
✓
popularity
WhichDB Score
2.4
45.9
Rank
#477
#36
GitHub stars
–
15.8K
Stack Overflow questions
122
381
scale & guarantees
Comfortable data size
Large (≤ 1 PB)
Massive (Multi-PB)
Horizontal scaling
Native
Native
Multi-region
Active active
Active active
ACID
Limited
Limited
Consistency
Strong, Eventual
Tunable, Eventual
Schema
Strict
Strict
Architecture
Distributed, Serverless
Distributed, Multi primary, Client server
deployment
Self-hosted
—
✓
Vendor-managed cloud
✓
✓
Serverless
✓
—
Embedded
—
—
Edge
—
—
Clouds
AWS
AWS, Google Cloud
capabilities
Transactions
✓
—
Joins
—
—
Secondary indexes
—
✓
Full-text search
—
—
Vector search
—
—
Geospatial
—
—
JSON
—
✓
Change data capture
✓
✓
Triggers
—
—
Stored procedures
—
—
Materialized views
—
✓
TTL / expiry
✓
✓
Pub/Sub
—
—
Columnar storage
—
—
In-memory
—
—
Durable persistence
✓
✓
Compression
—
✓
Encryption at rest
✓
✓
Role-based access
✓
✓
Time travel
✓
—
Branching
—
—
Online schema changes
—
✓
Streaming ingest
—
✓
Offline sync
—
—
Runs in WebAssembly
—
—
interfaces
Query languages
CQL
CQL, DynamoDB API
Client languages
Java, Python, JavaScript, Go, C#, Ruby
Java, Python, Go, Rust, C++, C#, JavaScript, Scala
Best for
OLTP, IoT, Time-series, Metadata
OLTP, Time-series, IoT, Feature store
Add more to this comparisonNot sure either fits? Try smart match

Amazon Keyspaces vs ScyllaDB: FAQ

What is the difference between Amazon Keyspaces and ScyllaDB?

Amazon Keyspaces: Serverless, CQL-compatible Cassandra service on AWS with no clusters to manage. ScyllaDB: C++ rewrite of Cassandra with shard-per-core design; also speaks the DynamoDB API. Licensing: Amazon Keyspaces is proprietary (Proprietary (AWS service)); ScyllaDB is source-available (ScyllaDB Software License Agreement 1.1). ScyllaDB is built for larger datasets (Multi-PB) than Amazon Keyspaces (≤ 1 PB). Only Amazon Keyspaces has transactions, time travel.

When should I choose Amazon Keyspaces over ScyllaDB?

Choose Amazon Keyspaces for moving existing Cassandra apps to AWS without ops, spiky workloads that suit on-demand pricing and serverless apps that need a CQL data model. Choose ScyllaDB for chat and messaging history at very high volume; low-latency feature stores for ML; and cassandra or DynamoDB migration targets.

Is Amazon Keyspaces or ScyllaDB more popular?

ScyllaDB ranks #36 on the WhichDB Score (45.9/100) and Amazon Keyspaces ranks #477 (2.4/100). Popularity is not fit: check the requirements that matter for your project.

Are Amazon Keyspaces and ScyllaDB open source?

No. Amazon Keyspaces is proprietary, closed-source software. Not in the OSI sense. ScyllaDB is source-available: you can read the code, but the license restricts some uses, typically offering it as a competing managed service. License: ScyllaDB Software License Agreement 1.1.