Bucardo vs Estuary

Bucardo is a free, open-source system for asynchronous PostgreSQL replication in multi-source and multi-target arrangements. It supports multi-way synchronization and one-direction master-standby replication. Users define named syncs that copy selected tables between a server and other servers. A Perl daemon listens for NOTIFY requests and connects to remote databases to copy data. Multi-source setups can use a standard conflict handler or a custom handler assigned per table. Configuration and replication databases require PostgreSQL 8.1 or later, while the configuration database also needs PL/pgSQL and PL/PerlU. The daemon needs a Unix-like operating system, is tested mainly on Linux and macOS, and does not run natively on Windows. Installation is available from source, RPM or Debian packages, and FreeBSD Ports. Bucardo does not replicate DDL or schema changes. The listed latest release is 5.6.0.

Estuary is a managed data integration platform for combining change data capture, batch, streaming, and app synchronization for analytics, operations, and AI. It supports transformations while data is moving, using SQL, Python, or TypeScript, and describes delivery as exactly once with end-to-end latency under 100 milliseconds. More than 200 prebuilt connectors cover databases, warehouses, SaaS apps, and cloud platforms, including Snowflake, BigQuery, Kafka, MySQL, and PostgreSQL. Customers can store data in their own cloud bucket for a duration they choose, and select public, private, or Bring Your Own Cloud deployment. Estuary lists SOC 2 Type II, HIPAA, HITECH, CCPA, and GDPR among its compliance standards, and says data is encrypted in transit and at rest. It is available through API, self-hosted, and web options. The indefinite free tier is limited to 10 GB per month and two concurrent connector instances; paid plans start at $100 a month.