Maximum match rates. Zero vendor JavaScript.
Every conversion is enriched with 30+ vendor identifiers — automatically. Higher match rates. Better attribution. More conversions counted. None of it requires a single third-party script in the browser.
Why vendor IDs matter
A first-party data platform means vendor JavaScript never runs in the browser. That is the whole point — better performance, stronger privacy, and complete data control.
But those vendor scripts do more than track events. They establish user identity. Google's gtag.js creates and maintains the _ga cookie. Meta's Pixel generates _fbp and _fbc. Without these identifiers, server-side event delivery is effectively anonymous — vendors cannot attribute conversions back to ad clicks or user sessions.
Datafly Signal solves this with three identity resolution methods that generate, capture, and enrich vendor IDs entirely server-side.
Self-generated vendor IDs
For the top vendors, Datafly Signal generates IDs in the correct format without any vendor JavaScript. This covers the vast majority of customer needs.
| Platform | Identifier Generated | Why it matters for attribution |
|---|---|---|
| Google Analytics 4 | GA4 Client ID | Required for GA4 Measurement Protocol attribution. Without it, every server-side event arrives anonymous. |
| Meta / Facebook | Browser Pixel ID (_fbp) | Increases Meta Event Match Quality and conversion attribution. Meta CAPI performance degrades significantly without it. |
| Meta / Facebook | Click ID (_fbc) | Ties server-side purchase events back to specific ad clicks. Critical for ROAS calculation accuracy. |
| TikTok | Browser ID (_ttp) | Required by TikTok Events API for user-level match. Without it, TikTok cannot deduplicate or attribute conversions. |
| Anonymous Browser ID | Pinterest Conversions API match quality depends on this identifier for users who have not logged in. | |
| Snapchat | Browser ID (_scid) | Required for Snap Conversions API. Enables conversion deduplication and attribution across Snapchat campaigns. |
All IDs are set as server-side first-party cookies — making them fully exempt from Safari's ITP restrictions, with a 400-day maximum lifetime. That's 57× longer than client-side cookies in Safari. Every event arriving within those 400 days carries the full set of vendor identifiers, maximising match rates and attribution accuracy across every platform.
Automatic click ID capture
When a user arrives from a paid ad, the landing page URL contains a click identifier. Datafly Signal automatically extracts these parameters and stores them as first-party cookies for use in server-side event delivery.
gclid, gbraid, wbraid
Google Ads
fbclid
Meta
ttclid
TikTok
epik
li_fat_id
msclkid
Microsoft / Bing
ScCid
Snapchat
rdt_cid
UTM parameters
All channels
Click IDs are critical for conversion attribution. By capturing them server-side and persisting them as first-party cookies, Datafly Signal ensures they survive Safari's ITP restrictions and remain available for the full attribution window.
Server-side identity enrichment
For vendors that require API credentials for identity resolution — such as Acxiom, Amperity, LiveRamp, and UID2 — Datafly Signal proxies the resolution entirely server-side. Credentials are stored securely in your cluster configuration and never reach the browser.
How it works
- 1The browser sends a first-party request to your Datafly Signal endpoint.
- 2Your cluster calls the vendor's identity API using credentials stored in your secure config.
- 3The resolved identity is stored securely for fast lookups on all subsequent events.
- 4All events for that user are automatically enriched with the resolved identity before delivery.
A persistent identity profile for every visitor
Every vendor identifier — self-generated, captured from URLs, or resolved via match-pixel sync — is stored persistently in your identity profile for that visitor. On every subsequent event, the full profile is automatically re-enriched and sent to every vendor. No manual lookups. No missing identifiers. No lost attribution.
30+
Vendor IDs stored
GA4, Meta, TikTok, Trade Desk, Criteo, LiveRamp, and 25+ more — all stored and re-enriched on every event.
400
Day profile lifetime
Identity profiles are retained server-side and survive cookie clears, browser updates, and ITP restrictions.
0
Extra configuration
ID enrichment is automatic. Every event is enriched with every stored identifier for that visitor — no rules to write.
What this means for match rates
Vendors like Meta, Google, and TikTok build internal match tables from every signal you send. The more identifiers present on each conversion event — pixel ID, click ID, hashed email, external user ID — the higher the probability that the event is matched to a known user in their advertising system. Unmatched conversions cannot be attributed. They cannot be used to train optimisation algorithms. They are invisible.
By automatically enriching every event with every stored vendor ID, Datafly Signal maximises match quality on every single conversion — not just the ones where users happened to accept all cookies on a recent visit.
Cross-domain identity that works in Safari
Traditional cross-domain tracking relies on third-party cookies or cookie-based link decoration — both of which Safari's Intelligent Tracking Prevention blocks or limits. Datafly Signal takes a fundamentally different approach.
Encrypted token hub
When a user navigates between your domains, Datafly Signal generates a short-lived encrypted token containing the user's identity. The token is passed via URL parameter — no cookies required.
Security by design
Tokens are encrypted with AES-256-GCM, have a 60-second TTL, and use single-use nonces. Even if intercepted, they cannot be replayed or decoded without your cluster's encryption key.
Unlike cookie-based cross-domain solutions that break in Safari, Datafly Signal's token-based approach works in every browser, on every device, without any special configuration.
How vendors match your data
Vendors like Meta and TikTok build internal match tables from the signals you send. Each conversion event can include multiple identifiers — fbc, fbp, external_id, hashed email, hashed phone — and the vendor uses these to match the event to a known user in their system.
Match quality improves over time
The more signals you send consistently, the better the vendor's match rate becomes. Even if a single identifier is missing on one event, the vendor can use other signals to match. This is why Datafly Signal sends every available identifier on every event.
Always send external_id alongside vendor IDs
Your internal user ID (hashed as external_id) is the most durable identifier. It survives cookie resets, browser changes, and device switches. Pair it with vendor IDs for the highest possible match rate.
See identity resolution in action
Request a demo and we'll walk you through how Datafly Signal generates vendor IDs, captures click identifiers, and enriches events — all without a single line of vendor JavaScript.