Rill

Overview

Rill is an open-source BI tool designed for fast operational dashboards. It can connect directly to the GCS Parquet files produced by the Decode GA4 events_external template, bypassing BigQuery entirely for high-speed queries — or connect to BigQuery if you prefer SQL-based modelling first.

Requirements

Rill CLI installed
Decode GA4 data exported using the events_external template, which stores transformed data in GCS as Parquet files
A Google Cloud service account with Storage Object Viewer access to your Decode GA4 GCS bucket

Setup

1. Install Rill

curl -s https://cdn.rilldata.com/install.sh | bash

2. Create a project

rill start my-project
cd my-project

3. Add the Decode GA4 GCS source

Create a source file (e.g. sources/events.yaml):

type: gcs
path: gs://your-bucket-name/your-dataset/events/**/*.parquet

Replace your-bucket-name and your-dataset with your actual values.

Rill will use your local gcloud credentials by default. To use a service account key file, set:

export GOOGLE_APPLICATION_CREDENTIALS=/path/to/key.json

4. Create a metrics view

Create a metrics file (e.g. metrics/events.yaml):

type: metrics_view
model: events
timeseries: partition_date
measures:
  - name: pageviews
    expression: count(*)
dimensions:
  - name: page_location
    expression: event_param.page_location
  - name: event_name

5. Start the dashboard

rill dev

This opens the Rill UI at http://localhost:9009 with a live dashboard over your Decode GA4 data.