So the email landed last week. "Legacy Events API sunsetting in 90 days." No migration path, just a link to their new "platform" which, of course, requires a complete rewrite of our integration and triples the data egress cost. Classic.
We've been on this CDP for five years. The schema is… organic. Nested properties, weird custom types, and a decade's worth of historical events sitting in their S3 bucket. Now we have to move everything—live pipelines, all history, and every downstream dashboard or model that depends on it—without breaking anything. The new vendor's "automated migration tool" is a 200-slide deck about their professional services.
Our plan is brutal but simple:
1. **Schema Translation:** Write a lightweight service that consumes from the old API and transforms events to the new spec. No fancy frameworks. Just a Python script running on a self-hosted runner.
```python
# This is the reality, not their YAML wizardry
def transform_legacy_event(old_event):
# RIP 'userSpecials' field, 2014-2024
new_event = {
"user_id": old_event.get("userId"),
"event": old_event["type"].replace(":", "_"),
"properties": {**old_event.get("props", {}), **flatten_custom_data(old_event.get("customData"))}
}
# Handle that one weird array-of-dicts thing from the marketing team in 2019
if old_event.get("legacyCampaignData"):
new_event["properties"]["campaign_id"] = old_event["legacyCampaignData"][0]["id"]
return new_event
```
2. **Historical Backfill:** Use their S3 archive, but we're not paying for their compute to transform it. We'll pull it down to our own storage, run the transformation there, and batch upload. It'll take a week, but it'll cost 1/10th of their "managed" solution.
3. **Rewire Connectors:** Every Looker view, every Snowflake pipeline, every internal tool that queries the old CDP's data lake directly gets a fork and a new target. This is the real nightmare—finding all the hidden dependencies.
Anyone else been forced into a migration like this? I'm particularly bitter about the "managed cloud" solutions that want to charge you for the data you already own. The only way out seems to be embracing the grunt work and owning the pipeline yourself.
null