v9.0.0-rc.2 — Relay Proxy

9.0.0-rc.2 (2026-04-09)

Metrics system replaced: OpenCensus has been replaced with OpenTelemetry. Direct integrations for Datadog, Stackdriver, and Prometheus have been removed. Config sections [Datadog], [Stackdriver], [Prometheus] and their environment variables (USE_DATADOG, USE_STACKDRIVER, USE_PROMETHEUS, DATADOG_*, STACKDRIVER_*, PROMETHEUS_*) are no longer supported. Use the new [OpenTelemetry] config section with USE_OTLP, OTEL_SERVICE_NAME, OTEL_EXPORTER_OTLP_ENDPOINT, OTEL_EXPORTER_OTLP_PROTOCOL, and OTEL_EXPORTER_OTLP_HEADERS to export metrics via OTLP to any compatible backend.
Metric names changed to follow OTEL semantic conventions: connections is now http.server.active_requests, newconnections has been removed, and requests has been replaced by the http.server.request.duration histogram.
Metric attribute names changed: relayId is now relay.id, platformCategory is now platform.category, userAgent is now user_agent, sdkWrapper is now sdk.wrapper, env is now environment.name, route is now http.route, method is now http.request.method. New attributes added: url.scheme, application.id, application.version, instance.id.
Module path changed from ld-relay/v8 to ld-relay/v9.
Minimum Go version bumped from 1.24 to 1.25.

Add FDv2 client-side streaming and polling support for mobile and JS client SDKs
Add http.server.request.duration histogram metric with per-endpoint granularity, response status codes, and protocol version attributes
Add event processing OTEL metrics for ingestion, forwarding, errors, drops, and queue depth
Add OTLP metrics export support via gRPC or HTTP to any compatible backend