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Max Heinritz


Backfills are scripts run via the command line that change production data. Backfills should be idempotent. There are two kinds of backfills:

Ideally backfills use service class methods rather than directly editing database data so that authorization, revision history, and logging codepaths are triggered consistently. But if they need to directly read/write from the database, that can be ok sometimes, especially for one-off backfills.

It’s nice to be able to generate boilerplate for backfills. A good tool for this is Hygen:

For example with a package.json script like this:

  "gen:backfill:one-off": "HYGEN_TMPLS=src/app/backfill/templates hygen backfill new --type one-off",

We can run yarn gen:backfill:one-off my-one-off-backfill to generate a file like this: