Why a private API key instead of OAuth?

Klaviyo's private API keys are the recommended server-to-server integration pattern and offer the scoping Admaxxer needs. OAuth is on the roadmap for customer-facing installs, but for our paste-key model the private key is simpler, more secure, and doesn't require Klaviyo partner review.

What about Klaviyo's rate limits?

Klaviyo's public rate limit is 150 requests/second for steady state (higher burst). Admaxxer's BullMQ queue caps effective request rate conservatively under that threshold per workspace. We'll never burn through your API budget.

Can you attribute revenue at the flow level?

Yes. The Events API exposes flow_id and flow_message_id on every send. Admaxxer stores these alongside Klaviyo-attributed orders so you can see which flow step drove the revenue, not just which flow.

How is profile matching handled?

By hashed email. The Admaxxer pixel captures email hashes at checkout (or on any form submission with an email field), which join to Klaviyo profiles server-side. No plaintext email ever leaves your systems for matching purposes.

What about GDPR / deletion rights?

Deletion requests propagate: if a customer requests deletion in Klaviyo or via your privacy flow, Admaxxer's paired profile records are purged through the same workspace-level privacy pipeline within 30 days. Audit log entry for every deletion.

Close the loop between paid acquisition and email LTV.

The Klaviyo integration that closes the loop between paid acquisition and email LTV

Connect Klaviyo to Admaxxer and see email LTV overlaid on your Meta + Google acquisition cohorts. Answers 'what's my true 90-day blended MER when email re-engagement is included?'

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What you get

Revenue sync: Klaviyo-attributed revenue (flows + campaigns) streams into Tinybird alongside pixel-tracked paid revenue. One denominator for every MER calculation.
Email LTV by channel: Which acquisition channel produces subscribers with the highest email LTV? Admaxxer joins Klaviyo profile LTV to the original Meta / Google / organic touch.
Segment performance by source: Klaviyo segments (VIPs, lapsed, high-AOV) broken down by the ad that originally acquired them. Spot segments over-indexed to a single hero campaign.
Flow attribution: Every Klaviyo flow (welcome, abandoned cart, browse abandonment, post-purchase) attributed per ad source — so you can measure email as a true acquisition multiplier.

How it connects

Create a Klaviyo private API key. In Klaviyo, go to Settings > API Keys > Create Private API Key. Scope: Read for Events, Orders, Profiles, and Segments. No write access requested.
Paste the key into Admaxxer. Paste the private key into Admaxxer — encrypted AES-256-GCM at rest. No OAuth round-trip needed for v1; Klaviyo private keys are the recommended server-to-server pattern.
Historical backfill + real-time webhook. Admaxxer backfills 90 days of Klaviyo events on connect, then subscribes to Klaviyo webhooks for new orders and flow sends — so email revenue lands in the dashboard in near real time.

Data Admaxxer reads

Data Admaxxer reads from Klaviyo
Dimension	What Admaxxer does with it
Events	Placed Order, Ordered Product, Started Checkout, Received / Opened / Clicked Email — timeline fodder for LTV reconstruction.
Orders	Klaviyo-attributed order data reconciled against your pixel-tracked revenue to flag double-counting.
Profiles	Email hash, first touch, first order date. Joined to ad-source data at the pixel cookie level.
Segments	VIP / lapsed / high-AOV membership. Used to overlay cohort segments on ad-source performance.
Flows	Flow name, step, revenue. Gives per-flow revenue attribution next to paid ads.
Campaigns	Sent campaign metadata — subject line, send time, revenue. Shown next to paid campaigns in the MER view.

Safety and security

Private API keys encrypted AES-256-GCM at rest. Never logged, never returned to the client.
Revocable in Klaviyo at any time — rotate or delete the key and Admaxxer's access stops immediately.
Read-only scopes: Events, Orders, Profiles, Segments. No sending, no editing flows.
Strict rate-limit respect — 150 requests/second ceiling, BullMQ-throttled per workspace.

Frequently asked

Why a private API key instead of OAuth?: Klaviyo's private API keys are the recommended server-to-server integration pattern and offer the scoping Admaxxer needs. OAuth is on the roadmap for customer-facing installs, but for our paste-key model the private key is simpler, more secure, and doesn't require Klaviyo partner review.
What about Klaviyo's rate limits?: Klaviyo's public rate limit is 150 requests/second for steady state (higher burst). Admaxxer's BullMQ queue caps effective request rate conservatively under that threshold per workspace. We'll never burn through your API budget.
Can you attribute revenue at the flow level?: Yes. The Events API exposes flow_id and flow_message_id on every send. Admaxxer stores these alongside Klaviyo-attributed orders so you can see which flow step drove the revenue, not just which flow.
How is profile matching handled?: By hashed email. The Admaxxer pixel captures email hashes at checkout (or on any form submission with an email field), which join to Klaviyo profiles server-side. No plaintext email ever leaves your systems for matching purposes.
What about GDPR / deletion rights?: Deletion requests propagate: if a customer requests deletion in Klaviyo or via your privacy flow, Admaxxer's paired profile records are purged through the same workspace-level privacy pipeline within 30 days. Audit log entry for every deletion.

Connect Klaviyo in under two minutes

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