The offer record connects the stack
Use Offers to define the product, price, checkout mode, invoice, and automation context before Substack and Kit (ConvertKit) receive events.
Integration pair
Substack + Kit (ConvertKit)
Use Substack and Kit (ConvertKit) together with Plandalf as the layer that ties checkout, payments, invoices, integrations, and lifecycle automation together.
Common setup
Most teams use Substack as their email layer and Kit (ConvertKit) as their email layer, with Plandalf in the middle handling the checkout, Offers, invoices, integrations, and the events that fire after a purchase.
See Substack and Kit (ConvertKit) docs for connection details.
Product surfaces behind this integration
This legacy integration URL now points builders toward the same product reality as the canonical app-pair guide: Offers, payment options, invoices, integrations, Automations, API docs, and webhooks.
Purchase automation carries the details
Automations and webhooks let Substack and Kit (ConvertKit) receive buyer, product, payment, invoice, coupon, and deadline context.
Use the richer guide from here
Keep moving from this page into canonical integration docs, platform pages, stack guides, and sequence recipes so every Substack or Kit (ConvertKit) mention has a useful next step.
Open canonical app-pair guide Use the richer Substack and Kit (ConvertKit) implementation guide. Substack platform page Roles, capabilities, and setup notes for Substack. Kit (ConvertKit) platform page Roles, capabilities, and setup notes for Kit (ConvertKit). API-first stack SDK checkout, API keys, webhooks, payment processors, and invoices.