EA Forum Update: Migrating to a new codebase

By Ollie Etherington @ 2026-06-29T11:24 (+68)

Summary: We’re making some big changes to the forum including a brand new post page. If you have any feedback, please let us know directly, or in the comments below.

The problem

The existing EA Forum codebase is relatively old and steeped in technical debt. New features and bug fixes (of which there are many) are slow, hosting is expensive, and server crashes are often time-consuming to fix. CEA also has considerably fewer resources dedicated to the forum than in the past (currently less than one full-time engineer), and we want to ensure the forum can continue to thrive in perpetuity whether or not that continues to be the case.

The forum has been developed alongside LessWrong for the past few years; both used the exact same code until recently, but with different configurations and different development teams. LessWrong completed their own migration last year, which consisted of taking the existing codebase and converting it to NextJS via some extremely large AI generated changes. This seems to have worked out nicely for them, but, for various reasons, we don’t believe that the same solution would have been right for us (that’s not to say that I think it was wrong for LessWrong, which is a very different site with very different requirements and plans).

The solution

We’ve started the process of creating a brand new codebase for the forum built on NextJS. We’ve set it up so that we can switch over one page at a time as and when they’re ready; for today's initial release we’ve migrated the home page, the post page, and a few simple ancillary pages such as the cookie policy and some admin pages. Together, these account for a little over 80% of all traffic, and we expect the rest of the site to take 12-18 months to release (bearing in mind that not all of our time will be dedicated to this project). We’ve also migrated the hosting from AWS to Render.

The home page is largely unchanged, though you may notice a few small UI updates such as some of the strange corner cases around how comments are displayed, and dark-mode users now have a much nicer colour hierarchy on all migrated pages.

The post page, however, has had some much more drastic changes that we’ve been planning for some time but never had time to implement including a new serif font (pitchforks at the ready) and a whole new layout for the title area at the top, which we hope you’ll find both clearer and more visually appealing.

We expect the new version to benefit in the following ways:

• It’ll be considerably easier for developers to add new features and fix existing bugs
• It’ll be quicker to onboard new developers, both as employees of CEA (we hope to be hiring soon!) and as open source contributors
• The site will generally be a little faster with bundle splitting, no unused code and much more efficient database queries
• We expect it to be notably cheaper to host; it’s very difficult to estimate exactly, but our worst estimates are that it will save a low number of thousands of dollars per year when finished, and our best estimates are that it will save a low number of tens of thousands of dollars per year
• The new hosting should be much more resilient to server failures and bot scraping which has caused us many headaches over the past few years (PSA to please use https://forum-bots.effectivealtruism.org/ for scraping rather than the main forum)
• It’s far more testable; despite only implementing a handful of pages we already have more tests (and higher coverage) than the old codebase
• We hope to be able to make the new forum more visually consistent, but this will take more time and work to fully realise

What this means for you

We hope that for most users this will be an unremarkable change. You may notice the odd visual update, bug fix, or simplification, but anything large and unannounced is probably unintentional, and we’d appreciate bug reports (if possible and applicable, please include screenshots and/or links). In any project of this size, some bugs will surely sneak through, but we’ll endeavour to fix them as soon as possible.

One of the advantages of this refactor is that it will help us build new features more quickly, so I’d also like to remind you that we still monitor the Forum Feature Suggestion Thread if there’s anything in particular you’d like to make a case for.

At some point in the next few weeks we’ll be moving the database from AWS to Render and this may incur a small amount of downtime (considerably less than an hour if all goes to plan); we’ll schedule this for a time of day with as few users as possible. We don’t anticipate any other planned outages in the foreseeable future.

Any and all feedback is welcome via the comments below, Intercom in the bottom right, or any of the usual ways of contacting the forum team.

Vasco Grilo🔸 @ 2026-07-02T09:13 (+2)

Hi Ollie. Thanks for the update.

I updated the last sentence of this comment, and some of its text went out of format. I am sharing a print below because I cannot copy the text which is out of format.

Ollie Etherington @ 2026-07-02T10:16 (+3)

Hi Vasco. Sorry about that - our Mathjax processing was being a bit overzealous and decided that your dollar signs were creating a math block. Should be fixed now - thanks for letting us know!

Vasco Grilo🔸 @ 2026-07-02T11:33 (+2)

No worries. Thanks for fixing it. The text looks good now.