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CRM ⇄ Business productivity

Affinity to Customer.io integration — real-time, two-way sync

Keep Affinity and Customer.io in sync without custom scripts. Cut weeks of integration work, eliminate silent data drift, and give your team a single, reliable source of truth.

  • SOC 2 and 6 other compliance frameworks
  • POC with real engineers in minutes

Adopted by fast-scaling companies moving mission-critical data in real time

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Why teams connect Affinity and Customer.io

Sync what happens in Customer.io with the customer records in Affinity, in real time and in both directions.

The CRM is supposed to be the record of every customer relationship, but customer-relevant information also accumulates in the other tools a team runs. Whatever Customer.io holds or produces that touches a customer, whether conversations, payments, replies, enriched data, or notes, the CRM only benefits if it arrives without someone copying it over.

Stacksync connects Segments, Campaigns, Broadcasts, Deliveries / Messages in Customer.io to Interactions, Reminders, Lists, List Entries in Affinity with bi-directional, real-time sync. Activity and record changes in Customer.io update the matching contact or account in Affinity, and CRM data flows the other way wherever Customer.io can store and use it.

Common use cases

  • 01 Keep unsubscribe and subscription-preference state consistent between Customer.io and the CRM to avoid compliance gaps.
  • 02 Sync account-level objects and their person relationships for B2B messaging keyed to company attributes.
  • 03 Mirror deal-flow lists into a warehouse or BI tool for pipeline and portfolio reporting.
  • 04 Push enrichment data computed elsewhere into Affinity field values on list entries.

Common sync patterns

Where Customer.io can store CRM context: fields kept current

Owner, lifecycle stage, or account details from Affinity sync into Customer.io, so people working there have the context without switching tools.

Where Customer.io handles support or shared inboxes

Tickets and conversations attach to the right contact and account in Affinity, so sales sees open issues before the next call.

Where Customer.io runs outreach

Prospects, sends, and replies sync into Affinity, keeping lead status current without manual imports.

What you can sync between Affinity and Customer.io

Representative objects on each side — any object or custom field can map to any target. Schemas are auto-detected; types are converted between the two systems.

Affinity objects Customer.io objects How this pairing syncs
Opportunities Deal records tracked on lists and synced with pipeline reporting. Events Behavioral events sent via the Track API that trigger campaigns. Opportunities is specific to Affinity and Events to Customer.io — each maps to any object or custom field on the other side.
Field Values Custom field data, either global or scoped to a list, mapped field-by-field in syncs. Segments Attribute- or event-based groups; data syncs feed the attributes segments evaluate. Field Values is specific to Affinity and Segments to Customer.io — each maps to any object or custom field on the other side.
Notes Meeting and call notes synced for record-keeping in other systems. Campaigns Automated workflows whose membership and metrics can be read via the App API. Notes is specific to Affinity and Campaigns to Customer.io — each maps to any object or custom field on the other side.
Interactions Automatically captured emails and meetings, read for activity reporting. Broadcasts One-off sends to segments or audiences, triggerable via API. Interactions is specific to Affinity and Broadcasts to Customer.io — each maps to any object or custom field on the other side.
Reminders Follow-up tasks associated with people and organizations. Deliveries / Messages Per-recipient message records whose lifecycle events flow out through reporting webhooks. Reminders is specific to Affinity and Deliveries / Messages to Customer.io — each maps to any object or custom field on the other side.
Lists Pipelines (deal flow, fundraising, portfolio) that structure most Affinity data; syncs usually target a specific list. Newsletters Recurring email sends with performance metrics available for reporting syncs. Lists is specific to Affinity and Newsletters to Customer.io — each maps to any object or custom field on the other side.

How changes propagate between Affinity and Customer.io

Each direction of the sync is driven by what the source system can signal and what the destination accepts — detection, delivery, and expected latency below.

Affinity Customer.io Sub-second propagation

DetectionAffinity notifies Stacksync of record changes through webhook events. Webhook subscriptions for record events, supplemented by polling.

DeliveryEach detected change is written to Customer.io through its API, with automatic retries and rate-limit backoff.

Customer.io Affinity Sub-second propagation

DetectionCustomer.io notifies Stacksync of record changes through webhook events. Reporting webhooks push message and delivery events.

DeliveryEach detected change is written to Affinity through its API, with automatic retries and rate-limit backoff.

Rate-limit considerations

  • Affinity: Subject to the platform's published API rate limits.
  • Customer.io: Subject to per-API rate limits documented by Customer.io.
What ships with Affinity ⇄ Customer.io

Connect Affinity and Customer.io for flexible, real-time data sync.

Real-time sync, workflow automation, event queues, EDI, and monitoring, for every Affinity–Customer.io connection.

Real-time

Two-way sync

Changes in Affinity or Customer.io instantly reflect in both systems. No stale data, no manual imports.

No-code + pro-code

Workflow automation

Trigger automated workflows whenever Affinity or Customer.io data changes, update records, fire webhooks, or kick off sequences without brittle API scripts.

At scale

Event queues

Handle millions of events per minute without losing a single Affinity or Customer.io record.

Observability

Monitoring

Track your Affinity ⇄ Customer.io sync health, view errors, and replay failed events in one click.

Trading partners

EDI

Transform legacy EDI complexity into simple database interactions between Affinity and Customer.io.

How the Affinity and Customer.io connectors work

Affinity

Integration surface
REST API
Authentication
API key
Change detection
Webhook subscriptions for record events, supplemented by polling
Capabilities
read · write · webhooks
Rate limits
Subject to the platform's published API rate limits

Customer.io

Integration surface
REST APIs split by purpose: Track API for data ingestion, App API for campaigns, people lookups, and messages
Authentication
Basic auth with site ID and API key for the Track API; bearer token for the App API
Change detection
Reporting webhooks push message and delivery events; person attribute changes are not streamed and require source-side detection
Capabilities
read · write · webhooks
Rate limits
Subject to per-API rate limits documented by Customer.io
How it works

How to connect Affinity to Customer.io — three steps, no code

Configure and sync within minutes, no code. Whether you sync 50k or 100M+ records, Stacksync handles the queues, infra, and plumbing. Integrations are non-invasive and need zero setup on your systems.

  1. 01

    Connect your apps

    Authenticate Affinity and Customer.io with each platform's native method — OAuth, API keys, or service accounts — plus secure options like SSH tunneling, IP whitelisting, and VPC peering.

    • OAuth 2.0
    • SSH tunnel
    • VPC peering
    Affinity connected
    Customer.io connected
    OAuth 2.0
    SSH tunnel
    SSL certificate
    VPC peering
  2. 02

    Choose tables

    Pick the Affinity and Customer.io objects to sync — Stacksync auto-detects both schemas, including custom fields where the platform exposes them. Sync to existing tables, or let Stacksync create new ones with ideal data types.

    • Standard objects
    • Custom objects
    • Auto-schema
    objects · Affinity ⇄ Customer.io
    Customers 12,480
    Sales Orders 8,213
    Invoices 5,902
    Items 1,344
  3. 03

    Map fields

    Fields map automatically even when names and types differ. Stacksync handles transformation and type casting for you, zero configuration required.

    • Auto-map
    • Type casting
    • Transforms
    Affinity Customer.io
    Company company_name text
    Email email text
    Amount amount numeric
    Created created_at timestamp
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FAQ

Affinity and Customer.io integration FAQ

SECURITY

Security teams trust Stacksync

As a data company, we understand the importance of keeping your data secure. Stacksync is built with security best practices to keep your data safe at every layer, and is DPF-certified for US, EU, UK and CH data transfers.

Learn more about security
SOC 2 Type II
ISO 27001
HIPAA BAA
GDPR
CCPA
DPF US-EU-UK-CH
→ SECURITY WITH BENEFITS

SSO & SCIM

Let your users access Stacksync from your centralized user management systems. Works with Okta, Azure, Google SSO and more.

Alerts

Immediately get alerted about record syncing issues over email, Slack, PagerDuty and WhatsApp. Resolve issues from a centralized dashboard with retry and revert options.

Secure connection options

Securely connects to your systems with:

OAuth 2 SSH Tunnelling SSL certificates IP Whitelisting VPN gateway VPC peering and more

Related integrations

Every pair below is a real-time, two-way sync. Search all 423 integrations available for Affinity and Customer.io.

Popular · 7 of 423
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