This blog is written in
Next.js. Buttondown's marketing site and docs site are written in Next.js. One advantage of this shared lineage is I get to tool around with various interesting ideas and learn more about Next.js esoterica in the cozy confines of a personal website before applying them more rigorously and pragmatically in a commercial sense. 1
When Vercel announced a new approach to handling OpenGraph generation, I was excited to play around with it. I had spent some time sniffing around for solutions for this site and for Buttondown and wasn't excited enough about any of them to dip my toes in the figurative waters.
To start with the conclusion: I'm really excited about @vercel/og;. I think it's a very nice library that delivers on a value proposition of "leverage the APIs and routing mechanisms that you're familiar with in
Next.js and avoid having to hook into Puppeteer or some kludgy rendering engine." I'm looking forward to integrating it with my other Next.js projects.
That being said — I stubbed my toe a number of times. (I think this is pretty reasonable, for what it's worth — it's a pre-v1.0 piece of software.) Here are all the places where I did so:
@vercel/og) refuses to recognize some external images for reasons passing understanding. I filed an issue on this, but it's the scariest thing by far — this blog, for instance, references around two thousand external images and these failures are silent, so I have no way of actually telling the extent of the problem.
.woff2webfonts (a known issue) because its backing font library doesn't support them either. Not the end of the world, but it meant I had to spend a few minutes googling around for a
.ttfversion of IBM Plex Sans.
@vercel/og, but a problem with Open Graph itself!) the translation layer from "looks good in a playground or as a rendered image" to "looks good on Twitter" is...murky. There are a number of validation tools like metatags.io which help somewhat, but even then you run into differences: for instance, Twitter zooms in slightly more on the OG image vertically than horizontally, meaning borders will look skewed. (There should really be a tool that makes this easier.)
OGendpoint through GET params, and if you want to pass more than one distinct datum React makes it very hard. (I kludged my away around this by passing a single key-value pair, where the
valueis a CSV.)
eslintissue that arose from me upgrading Next to
12.1So if you are googling around a solution for
next/server should not be imported outside of pages/_middleware.js— update your eslint-config-next, too!
If this sounds like a lot of nits and drawbacks, don't let it distract you from the larger point: I was able to get this up and running and deployed to production in around ninety minutes. I'm very happy with how it turned out, and excited to use it in other projects.
This is one of the biggest advantages of sticking to a few core technologies when building; knowledge transfers across codebases! ↩