Support for Postgres 18

[ThallesP]

If you really need a Postgres 18 instance, take a look at my template https://railway.com/deploy/postgresql-18. Please note that some features won't work, such as the data tab.

I was working on adding support for Postgres 18 but they've changed quite a few things regarding volume mount paths:

1. They now recommend using a major version in the mount path, e.g., /var/lib/postgresql/18/docker. I would recommend using the new path, though I understand it might cause issues with previous versions and possibly with Railway's underlying architecture. Using the new path offers the benefit of easier upgrades according to their documentation.

2. They've also changed the mount path to /var/lib/postgresql instead of /var/lib/postgresql/data. Not implementing this change results in issues:

/orchestrator.RouterLegacyService/StartDeployment UNKNOWN: crun: openat2 `var/lib/postgresql/data`: No such file or directory: OCI runtime attempted to invoke a command that was not found

I believe the Postgres 18 entrypoint or another dependency requires the volume to be mounted at /var/lib/postgresql. That will require the init scripts to support that new volume mount path and also Railway to change that.

My question is: should I implement both recommended changes (major version in path and new mount path) and have Railway adapt their approach, or should I implement only the new mount path, which appears to be the minimum requirement?

context:

• https://hub.docker.com/_/postgres#pgdata (docs)
• Change PGDATA in 18+ to /var/lib/postgresql/MAJOR/docker docker-library/postgres#1259 (reason on why)
• https://railway.com/project/636f1c4f-8c17-4afe-92cd-6c18b7f24dbf/service/12936ca6-83a4-4924-ab9a-f94ebb5177a9?environmentId=e7bcbd4b-2172-4230-aa21-c5a81d1fe264&id=72445d45-6187-480f-9c24-8558b1af26ae#build (errors on deploying it, feel free to do whatever on that service/project)
• add postgres 18 #31 (my PR, implements the new min mount path only)

[kinsyudev]

Please add support for this

[JoshuaNitschke]

Team Railway: Let's get this merged in/commented on please!

[mittalyashu]

@brody192 Before merging this change and allowing all the customers of Railway simply doing the version bump.

Can you check-in with the internal engineering team at Railway as to show some kind of warning for this version bump?

[Ryner01]

Do we know when this is going the merged?

[yousafsabir]

Merge this man.

[l0gicgate]

Can the Railway team address why this isn't being merged?

[ThallesP]

Hi, for anyone reading this, Railway has already provided reasons on why this isn't being merged at the moment.

PostgreSQL 18 requires additional work for deployment and isn't as straightforward to implement as previous versions. Please be patient or use my template if you really need PostgreSQL 18.

[nedpearson]

fixed

[nedpearson]

ixed