Implementation Server-Side High

GTM Server-Side Implementation

Browser-side tracking is failing. Ad blockers, ITP, third-party cookie deprecation you need server-side tracking. We implement sGTM on the platform that fits your needs, migrate your tags, and hand you a system you own.

20-40 hours

Why Server-Side Tracking Matters Now

Client-side tracking is losing ground fast. Safari's Intelligent Tracking Prevention limits cookie lifetimes to 7 days (or 24 hours for classified trackers). Firefox blocks known tracking domains by default. Ad blockers strip 25-40% of your analytics data. And third-party cookies are on their way out entirely.

Server-side GTM fixes this by moving tag execution from the browser to a server you control. Data flows through your subdomain first-party context. You control what data reaches each vendor. Cookies are set server-side with longer lifetimes. Ad blockers can't block requests to your own domain.

But server-side GTM is not a toggle you flip. It's infrastructure work. You need a hosting platform, a subdomain, custom clients to receive incoming data, server-side tags configured differently from their client-side equivalents, and a migration plan that doesn't lose data during the transition.

We handle all of it. We help you choose the right hosting platform based on your traffic volume, budget, and technical requirements not because we have a referral deal with a specific provider. We build the server container, develop custom clients when needed, migrate your tags methodically, and run parallel tracking until the data matches.

Implementation Process

Infrastructure Assessment & Platform Selection

We evaluate your traffic volume, geographic distribution, budget, and technical team capabilities to recommend the right hosting platform. Stape for simplicity, Google Cloud for control, TAGGRS for EU hosting, Addingwell for premium support, or custom infrastructure for maximum flexibility.

Subdomain & DNS Configuration

We set up the subdomain that will proxy requests to your server container (e.g., data.yourdomain.com). DNS records, SSL certificates, and proxy configuration all handled. This is what makes your tracking first-party.

Server Container Build

We create the server-side GTM container with the appropriate clients (GA4, Meta CAPI, Google Ads, etc.), configure data transformation logic, and set up proper event routing. Custom clients are developed when standard templates don't fit your data structure.

Tag Migration

Tags are migrated from client-side to server-side execution. Not all tags should move we determine which tags benefit from server-side processing and which should stay client-side. Each migration is tested individually before combining.

Parallel Tracking & Validation

We run both client-side and server-side tracking simultaneously and compare the data. Discrepancies are investigated and resolved before the cutover. This phase ensures zero data loss during the transition.

Documentation & Knowledge Transfer

You receive complete documentation of the infrastructure, container architecture, and maintenance procedures. Plus a hands-on training session so your team can manage and extend the setup independently.

What Makes This Different

Platform-agnostic. We don't push Stape because we're a partner. We recommend the platform that fits your needs. Some clients need Google Cloud's flexibility. Others need Stape's simplicity. We've deployed on all of them.

Custom client development. When standard tag templates don't fit, we build custom clients and tags. This is where most agencies stop because it requires actual server-side JavaScript development.

No vendor lock-in. Everything we build, you own. Full documentation, source code for custom clients, and knowledge transfer. You can maintain it in-house or switch providers.

Consent-integrated. Server-side tracking doesn't bypass consent. We integrate Consent Mode v2 signals into the server container so vendor data flows still respect user choices.

Parallel validation. We don't just deploy and hope. Parallel tracking with data comparison ensures the migration is accurate before any client-side tags are removed.

Post-launch monitoring. AssertionHub can continuously validate that server-side events are flowing correctly after launch.

Deliverables

Working Server-Side GTM Container Fully configured with clients, tags, and data transformation logic
Infrastructure Documentation Platform setup, DNS configuration, SSL, scaling parameters
Tag Migration Map Which tags moved server-side, which stayed client-side, and why
Custom Client Source Code If custom clients were developed, you get the full source with comments
Parallel Tracking Report Data comparison between client-side and server-side showing parity
Training Session 60-minute hands-on walkthrough with your team for ongoing management

Frequently Asked Questions

Will server-side GTM fix my ad blocker data loss?

Significantly, yes. Because requests go through your subdomain (first-party), most ad blockers don't block them. Real-world improvement is typically 20-35% more data collected, depending on your audience's ad blocker usage.

Which hosting platform do you recommend?

It depends on your needs. Stape is the easiest to manage and most cost-effective for standard setups. Google Cloud gives you full control and scales well. TAGGRS offers EU-hosted infrastructure for data residency requirements. Addingwell provides premium support. We'll recommend based on your specific situation.

Do we need a developer on our side?

For the implementation itself, no we handle everything. But for ongoing maintenance (adding new tags, updating custom clients), someone on your team should be comfortable with server-side GTM basics. Our training session covers this.

How does this work with Consent Mode?

We integrate Google Consent Mode v2 signals into the server container. When a user denies consent, server-side tags respect that decision. This is critical moving to server-side doesn't mean ignoring consent.

What about Meta CAPI, TikTok Events API, etc.?

Server-side GTM is the ideal way to implement Conversions APIs. We configure Meta CAPI, Google Ads Enhanced Conversions, TikTok Events API, and others as part of the server-side container. These APIs work best when called server-side.

Prerequisites

• Existing GTM web container
• DNS access for subdomain setup
• Decision on hosting platform (we help with this)

Assumptions (for 20-40 hours)

• Up to 50 tags to evaluate for migration
• Standard GA4, Meta CAPI, Google Ads setup
• Basic to moderate custom client complexity