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Arroyo vs Feldera

Arroyo: A Rust stream processor with SQL pipelines, now owned by Cloudflare and powering Cloudflare Pipelines. Feldera: An incremental SQL engine grounded in DBSP theory that updates any SQL query from changes only.

key differences

  • Transactions: Arroyo offers none ACID; Feldera offers limited.
  • Only Feldera has change data capture.
  • Arroyo has a serverless option; Feldera does not.

choose arroyo for

  • +Streaming ingestion into Iceberg/R2
  • +Real-time aggregation of Kafka events
  • +Lightweight Flink replacement for SQL pipelines

best at · Streaming, Real-time analytics, Lakehouse

choose feldera for

  • +Incremental computation of complex analytics over changing data
  • +Real-time feature engineering
  • +Streaming ETL into Delta Lake or Iceberg

best at · Streaming, Real-time analytics, Feature store

ArroyoA Rust stream processor with SQL pipelines, now owned by Cloudflare and powering Cloudflare Pipelines.
FelderaAn incremental SQL engine grounded in DBSP theory that updates any SQL query from changes only.
overview
Primary model
Relational
Relational
Also supports
–
–
Type
Database engine
Database engine
Status
Active
Active
Developer
Cloudflare (Arroyo Systems)
Feldera, Inc.
First release
2023
2023
Latest version
0.15.0 (Dec 1, 2025)
0.369.0 (Oct 23, 2026)
License
Open source (permissive)Apache License 2.0
Open source (permissive)MIT (open-source edition); Enterprise is commercial
Free tier
✓
✓
popularity
WhichDB Score
5.4
15.8
Rank
#385
#202
GitHub stars
5.1K
2.1K
Stack Overflow questions
–
–
scale & guarantees
Comfortable data size
Medium (≤ 10 TB)
Medium (≤ 10 TB)
Horizontal scaling
Native
Native
Multi-region
None
None
ACID
None
Limited
Consistency
Strong
Strong
Schema
Strict
Strict
Architecture
Distributed, Single node, Client server
Single node, Distributed, Client server
deployment
Self-hosted
✓
✓
Vendor-managed cloud
✓
✓
Serverless
✓
—
Embedded
—
—
Edge
—
—
Clouds
Cloudflare
AWS
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
SQL (DataFusion dialect)
SQL (Apache Calcite dialect)
Client languages
–
Python, Rust
Best for
Streaming, Real-time analytics, Lakehouse
Streaming, Real-time analytics, Feature store, Lakehouse
Add more to this comparisonNot sure either fits? Try smart match

Arroyo vs Feldera: FAQ

What is the difference between Arroyo and Feldera?

Arroyo: A Rust stream processor with SQL pipelines, now owned by Cloudflare and powering Cloudflare Pipelines. Feldera: An incremental SQL engine grounded in DBSP theory that updates any SQL query from changes only. Transactions: Arroyo offers none ACID; Feldera offers limited. Only Feldera has change data capture. Arroyo has a serverless option; Feldera does not.

When should I choose Arroyo over Feldera?

Choose Arroyo for streaming ingestion into Iceberg/R2, real-time aggregation of Kafka events and lightweight Flink replacement for SQL pipelines. Choose Feldera for incremental computation of complex analytics over changing data, real-time feature engineering and streaming ETL into Delta Lake or Iceberg.

Is Arroyo or Feldera more popular?

Feldera ranks #202 on the WhichDB Score (15.8/100) and Arroyo ranks #385 (5.4/100). Popularity is not fit: check the requirements that matter for your project.

Are Arroyo and Feldera open source?

Yes. Arroyo is open source. License: Apache License 2.0. Yes. Feldera is open source. License: MIT (open-source edition); Enterprise is commercial.