What's New in Salesforce API Version 64.0, And why It Matters for Marketo Engage Users

Marketo Engage has upgraded the Salesforce Integration to API version 64. The upgrade unlocks a host of new capabilities and changes.

Salesforce API version 64.0 shipped as part of the Summer '25 release, and it brings a mix of breaking changes, platform enhancements, and quality-of-life improvements for anyone building or maintaining integrations on the Salesforce platform. If your org talks to Marketo, whether through the native Salesforce-Marketo Sync, a middleware layer, or custom REST/SOAP calls, several of these changes are worth planning around. Here's a rundown of what's new, and how it plays out in practice for Marketo-connected orgs.

Breaking Changes and Deprecations to Know About

Legacy API versions are officially retired. Salesforce has sunset API versions 21.0 through 30.0 across REST, SOAP, Bulk, and Tooling APIs. Any integration still pointed at one of these versions, including old Marketo sync connections that were never upgraded, will start failing rather than degrading gracefully.

My Domain URLs are now required for API access. Salesforce now requires API calls to route through the org's My Domain login URL rather than generic instance URLs. This supports Hyperforce's domain-based routing model and reduces friction during instance migrations, but it means any hardcoded endpoint URLs in middleware or scripts need to be updated.

Outbound Message timeouts got shorter. The timeout window dropped from 60 seconds to 20 seconds, tightening up asynchronous integration performance but putting pressure on slower downstream endpoints.

Salesforce Functions is retired. Teams using Functions for custom serverless logic need to migrate to Apex + Async Apex, or move that logic to an external serverless platform triggered via Event Relay.

Platform API Enhancements

A few developer-facing improvements stand out:

• OpenAPI specification support for the sObjects REST API (Beta): lets developers auto-generate client SDKs and documentation and explore metadata dynamically with wildcard URIs.
• Streaming API disconnect notifications: a new /meta/disconnect channel tells subscribers when a connection drops, so event-driven integrations can detect and recover from dropped sessions faster.
• Composite API monitoring: two new Event Monitoring event types, CompositeApi and CompositeApiSubrequest, give much finer visibility into how composite/batched requests are performing.

Metadata and Tooling Improvements

• A new rootTypesWithDependencies parameter pulls in related metadata types automatically during deployment, cutting down on dependency errors.
• Pilot metadata types can now be retrieved and deployed in v64.0, giving early adopters a path to test upcoming features.
• The Metadata Coverage Report has been redesigned into a more interactive tool for checking deployment readiness.
• Pub/Sub API is now generally available across all Hyperforce regions, which matters for anyone building real-time, event-driven architectures at scale.

Sales Cloud, Data Cloud, and Service Cloud Updates

• Agentforce capabilities expanded, including multilingual outreach via Agentforce SDR and sales-process adherence checks via Agentforce Deal Agent.
• The native LinkedIn Lead Sync is being deprecated; orgs need to enable the newer "LinkedIn Lead Gen" connection setting to keep lead capture flowing.
• Data Cloud picked up Direct-DMO and Copy Field enrichments for related records, plus the ability to promote enrichments from sandbox to production via deployment APIs (useful for teams running proper CI/CD pipelines).
• Event Relay configurations are now packageable, so ISVs and enterprise teams can distribute pre-built real-time event forwarding setups inside managed packages.
• Field Service APIs gained better structured data capture (PDF, NPS, forms) and route conflict handling.

Industry Cloud Highlights: Financial Services, Public Sector, and Education

Alongside the core platform API changes, Summer '25 brought meaningful updates to Salesforce's industry-specific clouds, several of which include their own dedicated APIs and objects that matter if your org sits in a regulated or mission-driven vertical.

Financial Services Cloud (Finance Cloud)

• Actionable Segmentation is now generally available, giving relationship managers a way to build timely, personalized client outreach programs directly off of CRM data.
• Scoring Framework adds predictive scoring so teams can prioritize which customers to engage first.
• Agentforce for Financial Services: Banking Service Assistance handles routine banking inquiries automatically, cutting case resolution time with AI-driven guidance baked into the same records structure.

Government / Public Sector Solutions (Gov Cloud)

• Agentforce for Public Sector Complaints: gives agencies an AI-assisted way to intake and route constituent complaints faster.
• Grantmaking functionality (shared with Nonprofit Cloud) continues to mature, supporting the full lifecycle of awarded grants.
• Public Sector Solutions is also flagged as one of the fastest-growing areas of new feature investment this release, alongside continued OmniStudio and Context Service API support for eligibility and case management workflows.

Education Cloud

• New dedicated APIs for student holds let institutions programmatically create holds and fetch the violations tied to them, with a new Hold Instance View for tracking everything in one place.
• Agentforce for Education - Student Recruitment: answers prospective student questions around the clock, registers them for campus tours, and can kick off applications; all exposed through the same Agentforce action framework as other clouds.
• Enhancements to the application review process now support customized rubrics per review stage (application review vs. phone interview vs. in-person interview), assignable by an application's internal status.

For Marketo Engage customers running Financial Services, Public Sector, or Education Cloud, these updates matter beyond their home cloud. The Agentforce actions and scoring/segmentation data they generate are ordinary Salesforce records and are addressable the same way any lead, contact, or custom object is, through the standard Marketo sync fields and lead-scoring logic described below.

Where This Gets Interesting for Marketo Customers

Marketo Engage integrates with Salesforce in one of a few common ways: the native Sync, a middleware/iPaaS layer (like MuleSoft or Workato), or custom REST/SOAP/Bulk API calls built by an internal team. A handful of the v64.0 changes have direct implications for that setup:

API version retirement is a forcing function to check your sync health. If your Marketo-Salesforce sync, or any custom lead/contact sync job, was built years ago on an old API version, this release is the moment it either gets flagged or silently starts failing. It's a good prompt to audit which API version your sync jobs, custom Apex triggers, or middleware connectors are actually calling, and bump anything below the supported range.

My Domain enforcement affects custom integrations more than the native sync. Marketo's out-of-the-box Salesforce sync generally handles domain routing on its own, but any custom REST calls your team built (e.g., a nightly job that pushes lead scores from Marketo into custom Salesforce fields via API) need to be pointed at the org's My Domain URL, not a legacy instance URL.

Streaming API disconnect handling helps real-time lead routing stay reliable. If you've built anything on Salesforce's Streaming or Pub/Sub API to push Marketo activity data (form fills, email engagement, program membership) into Salesforce in near real-time, the new disconnect notifications mean you can detect a dropped session and reconnect automatically instead of silently losing events (a common pain point in high-volume ABM or lead-scoring pipelines).

Faster Outbound Message timeouts matter if Salesforce triggers Marketo actions. Some orgs use Salesforce workflow rules or outbound messages to notify Marketo (via a listener endpoint) when a lead status changes. With the timeout cut to 20 seconds, any endpoint that's slow to respond risks silently failing notifications; worth a load test if your architecture depends on this pattern.

Data Cloud enrichments open new options for unifying Marketo and Salesforce data. For customers who've also adopted Data Cloud, the new Direct-DMO and Copy Field enrichments make it easier to blend Marketo engagement history with Salesforce CRM data on the same customer record; useful for building richer segmentation without custom ETL work.

Composite API monitoring helps diagnose sync performance issues. Marketo's sync and many middleware tools rely on Composite API calls to batch operations efficiently. The new CompositeApi and CompositeApiSubrequest event types give admins a way to see where sync slowdowns are coming from, rather than guessing.

Industry cloud scoring and segmentation data can feed Marketo lead scoring directly. If your org runs Financial Services Cloud's Scoring Framework, Education Cloud's application/rubric data, or Public Sector's case and grant records, those fields live on standard or custom Salesforce objects. That means they can be synced into Marketo the same way any other field is, and used inside Marketo smart lists and lead scoring models. A wealth-management team using Actionable Segmentation, for instance, can push segment membership into Marketo to trigger a matching nurture track without building a separate integration. Likewise, an admissions office using the new rubric-based application review stages could sync stage or score fields into Marketo to time recruitment nurture emails around where a prospective student actually sits in the review pipeline.

The Bottom Line

API v64.0 isn't a dramatic overhaul, but it tightens up performance, observability, and domain security in ways that ripple into any Marketo-Salesforce integration. Your native sync and any custom integrations are on a supported API version. Update hardcoded URLs to use My Domain, and if you're leaning on Streaming API or outbound messages for real-time Marketo-Salesforce workflows, take advantage of the new resiliency features before they become a troubleshooting fire drill.

For the full technical details, see Salesforce's official Summer '25 release notes for API version 64.0.