Hi Stephen,
Thanks for reaching out. There may be reusable parts of your custom implementation, but the new Ads API is different from the old SOAP AdWords API. I'd recommend looking through the
migration guide for more details on this. Like the AdWords API, the Ads API client libraries support
code samples for almost all operations supported in the API.
Please let us know if you have any specific questions on the new API.
Regards,
Matt
Google Ads API Team

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