--- title: "How to hack Logical Replication in PostgreSQL: Insights from contributors" url: https://daily.dev/posts/how-to-hack-logical-replication-in-postgresql-insights-from-contributors-a6lbt9nt5 source_url: https://postgr.es/p/9kE type: article source: "Planet PostgreSQL" published: 2026-05-31T07:44:28.635Z updated: 2026-05-31T09:05:07.938Z tags: ["open-source", "performance", "backend", "postgresql"] reading_time: 14 upvotes: 0 comments: 0 language: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # How to hack Logical Replication in PostgreSQL: Insights from contributors **[Planet PostgreSQL](https://daily.dev/sources/planet-postgresql)** · 14 min read · 0 upvotes · 0 comments ## Summary A deep-dive guide for contributors working on PostgreSQL logical replication, written by Fujitsu engineers. Covers practical lessons across four contribution areas: performance optimization (profiling with perf, eliminating unnecessary relcache access), bug fixing (using BuildFarm and Patch Tester, analyzing feature intersections like MERGE command), code refactoring, and new features. Also addresses publication DDL semantics, lazy vs. eager validation, upgrade/downgrade compatibility across major versions, historic snapshot behavior in catalog lookups, subscriber worker architecture (apply, parallel apply, tablesync, sequencesync workers), and why physical replication patterns don't always translate to logical replication. Emphasizes streaming mode as the primary optimization target. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Postgres Migrations Using Logical Replication](https://daily.dev/posts/postgres-migrations-using-logical-replication-h3ti7rqrp) · Crunchy Data · 5 upvotes · 0 comments - [How To Run Logical Replication On A Production PostgreSQL Cluster](https://daily.dev/posts/how-to-run-logical-replication-on-a-production-postgresql-cluster-xxhfriitx) · Planet PostgreSQL · 0 upvotes · 0 comments --- Tags: [#open-source](https://daily.dev/tags/open-source), [#performance](https://daily.dev/tags/performance), [#backend](https://daily.dev/tags/backend), [#postgresql](https://daily.dev/tags/postgresql) [View this post on daily.dev](https://daily.dev/posts/how-to-hack-logical-replication-in-postgresql-insights-from-contributors-a6lbt9nt5)