Ruohang FengCreator of Pigsty & founder of PGSTY, PostgreSQL contributor & database architect (@Vonng).

pg_mooncake 0.3.0 — released alongside duckdb_mooncake v0.0.2 and moonlink v0.0.1 — is the first release of the Mooncake real-time analytics suite maintained by PGSTY:

• pgsty/pg_mooncake v0.3.0 (MIT)
• pgsty/duckdb_mooncake v0.0.2 (MIT)
• pgsty/moonlink v0.0.1 (BSL-1.1 with PG_MOONCAKE LINKING & DISTRIBUTION EXCEPTION, client crates MIT)

Binary RPM and DEB packages for PostgreSQL 14, 15, 16, 17, and 18 across RHEL / Rocky / AlmaLinux 8, 9, 10 and Debian 12/13, Ubuntu 22.04/24.04 (x86_64 and aarch64) are available through the PGEXT repository and Pigsty.

Highlights of pg_mooncake 0.3.0

1. Upgraded to pgrx 0.19.3 & PostgreSQL 14–18

pg_mooncake has been migrated to pgrx = 0.19.3 (cargo-pgrx 0.19.3), bringing first-class support for PostgreSQL 18 alongside PostgreSQL 14, 15, 16, and 17:

• Updated extension metadata in pg_mooncake.control (default_version = '0.3.0') and added the upgrade script sql/pg_mooncake--0.2.0--0.3.0.sql.
• Replaced legacy C string literals with Rust native CStr (c"...") across GUC definitions (mooncake.timeline_id, mooncake.enable_local_bucket, mooncake.default_bucket, mooncake.enable_memory_metadata).

2. DuckDB 2.0.0 & pg_duckdb 1.2.0 Adaptation

pg_mooncake 0.3.0 embeds pg_duckdb v1.2.0 and duckdb_mooncake v0.0.2, built against DuckDB v2.0.0 (d54cbbe3df17e8e5ce68312f483b4155836112aa):

• Ported duckdb_mooncake to the DuckDB 2.0 TableCatalogEntry, StorageExtensionInfo, and TableFilterSet iterator APIs.
• Fixed column-index remapping for IS NULL and IS NOT NULL filter pushdown in MooncakeScanFunction, preventing segmentation faults when multi-column filters are pushed down to Moonlink Parquet scans.
• Added a runtime pg_duckdb version check during worker initialization that enforces pg_duckdb = 1.2.0 (accepting 1.2.0 or 1.2.0-* pre-release suffixes and failing fast with a clear diagnostic message on mismatched versions such as 1.1.3 or 1.3.0).

3. LSN-Consistent Snapshot Reads (pg_current_wal_flush_lsn)

Previously, duckdb_mooncake constructed Moonlink table scan descriptors with lsn = 0, returning immediately without waiting for recently committed PostgreSQL transactions to be ingested by the background logical replication worker.

In v0.3.0, pg_mooncake exports mooncake_get_postgres_lsn() (calling pg_current_wal_flush_lsn() when in a normal backend session and 0 during recovery), and duckdb_mooncake resolves that symbol via dlsym(RTLD_DEFAULT, "mooncake_get_postgres_lsn"). Every analytical query against a columnstore table now waits until Moonlink has caught up to the PostgreSQL WAL flush LSN before scanning.

4. Partitioned Table Hierarchy Support (REPLICA IDENTITY FULL)

When calling mooncake.create_table(dst, src) on a partitioned PostgreSQL table, pg_mooncake 0.3.0 now walks the inheritance tree (find_all_inheritors) and sets REPLICA IDENTITY FULL on both the parent table and every leaf partition before adding the root table to the logical replication publication.

5. Explicit 0A000 Error for Deprecated mooncake.load_files

The legacy v0.1 helper mooncake.load_files(dst TEXT, files TEXT[]) now raises ERRCODE_FEATURE_NOT_SUPPORTED (0A000) with a clear migration message instead of silently panicking (todo!()).

6. Cargo Dependency Security Audit (RustSec)

All three Cargo workspaces (pg_mooncake, moonlink, duckdb_mooncake/moonlink_ffi) underwent a comprehensive security remediation against the RustSec Advisory Database (2026-11-05):

• pg_mooncake/Cargo.lock: reduced vulnerabilities from 33 to 6 (-82%) and eliminated all unsoundness warnings (1 -> 0).
• moonlink/Cargo.lock: reduced vulnerabilities from 46 to 15 (-67%) and eliminated all unsoundness warnings (1 -> 0).
• duckdb_mooncake/moonlink_ffi/Cargo.lock: 0 vulnerabilities, 0 unsound, 0 warnings.
• Upgraded tonic 0.14.5, prost 0.14.3, bincode 2.1.0, opentelemetry 0.31.0, wasmtime 43.0.1, rustls 0.23.37, aws-lc-rs 1.16.3, bytes 1.11.1, tar 0.4.45, and lz4_flex 0.11.6. See the SBOM & Security Audit page for full details.

Validation Summary

pg_mooncake 0.3.0 was validated end-to-end on both Ubuntu 24.04.5 LTS ARM64 (PostgreSQL 18.6) and Rocky Linux 10.2 ARM64 (PostgreSQL 17.11):

• 58/58 Moonlink table_handler unit tests passed.
• 3/3 pg_Regression SQL suites (small, partition, unsupported) passed (0 failures).
• Runtime version check verified: rejected pg_duckdb 1.1.3 and 1.3.0, accepted 1.2.0.
• 11/11 real-time replication, UPDATE/DELETE, partition, Iceberg metadata, and crash-restart persistence checkpoints passed.