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EJDB vs PoloDB

EJDB: Embeddable JSON document database in C, with a JQL query language and optional HTTP/WebSocket server. PoloDB: Embedded BSON document database for Rust with a MongoDB-like API and optional wire-protocol server.

key differences

  • Transactions: EJDB offers limited ACID; PoloDB offers full.
  • Only PoloDB has transactions, compression.

choose ejdb for

  • +Embedded JSON storage in desktop or IoT apps
  • +Mobile apps needing a local document store
  • +Lightweight local services with an HTTP API

best at · Embedded, Mobile/offline, IoT

choose polodb for

  • +Rust desktop and CLI apps needing local document storage
  • +Edge services wanting MongoDB-like semantics without a server
  • +Tests that stub MongoDB with an embedded store

best at · Embedded, Edge, Coordination

EJDBEmbeddable JSON document database in C, with a JQL query language and optional HTTP/WebSocket server.
PoloDBEmbedded BSON document database for Rust with a MongoDB-like API and optional wire-protocol server.
overview
Primary model
Document
Document
Also supports
–
–
Type
Embedded library
Embedded library
Status
Active
Active
Developer
Softmotions (Anton Adamansky)
PoloDB project (Vincent Chan)
First release
2012
2020
Latest version
2.95 (Oct 22, 2026)
5.3.0 (Jul 26, 2026)
License
Open source (permissive)MIT License
Open source (permissive)Apache License 2.0
Free tier
✓
✓
popularity
WhichDB Score
4.5
3.2
Rank
#401
#443
GitHub stars
1.5K
1.2K
Stack Overflow questions
–
–
scale & guarantees
Comfortable data size
Small (≤ 100 GB)
Small (≤ 100 GB)
Horizontal scaling
None
None
Multi-region
None
None
ACID
Limited
Full
Consistency
Strong
Strong
Schema
Schemaless
Schemaless
Architecture
Embedded, Single node
Embedded, Client server
deployment
Self-hosted
✓
✓
Vendor-managed cloud
—
—
Serverless
—
—
Embedded
✓
✓
Edge
—
—
Clouds
–
–
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
JQL
MongoDB-like query API (subset)
Client languages
C, JavaScript, Java, Swift, Dart, Kotlin
Rust, Python
Best for
Embedded, Mobile/offline, IoT, Coordination
Embedded, Edge, Coordination
Add more to this comparisonNot sure either fits? Try smart match

EJDB vs PoloDB: FAQ

What is the difference between EJDB and PoloDB?

EJDB: Embeddable JSON document database in C, with a JQL query language and optional HTTP/WebSocket server. PoloDB: Embedded BSON document database for Rust with a MongoDB-like API and optional wire-protocol server. Transactions: EJDB offers limited ACID; PoloDB offers full. Only PoloDB has transactions, compression.

When should I choose EJDB over PoloDB?

Choose EJDB for embedded JSON storage in desktop or IoT apps, mobile apps needing a local document store and lightweight local services with an HTTP API. Choose PoloDB for rust desktop and CLI apps needing local document storage; edge services wanting MongoDB-like semantics without a server; and tests that stub MongoDB with an embedded store.

Is EJDB or PoloDB more popular?

EJDB ranks #401 on the WhichDB Score (4.5/100) and PoloDB ranks #443 (3.2/100). Popularity is not fit: check the requirements that matter for your project.

Are EJDB and PoloDB open source?

Yes. EJDB is open source. License: MIT License. Yes. PoloDB is open source. License: Apache License 2.0.