Rill
Rill is an open-source BI tool built on DuckDB (and optionally ClickHouse) that turns SQL models and YAML metrics definitions into fast, interactive dashboards.
Overview
Rill (from Rill Data) is a business intelligence tool aimed at giving analysts sub-second, exploratory dashboards without standing up a separate cloud warehouse for every project. It's built "BI as code": data sources, SQL transformation models, and metrics definitions live as files in a project directory, so they can be version-controlled and code-reviewed like any other engineering artifact, then compiled into interactive dashboards.
Why DuckDB
Rill Developer (the open-source, local-first product) uses DuckDB as its default embedded OLAP engine. When Rill's creators evaluated engines for a tool that needed to feel instant while iterating on a dashboard, DuckDB's single-node analytical query performance made it the natural fit — data gets ingested from sources (files, object storage, warehouses) into DuckDB, and every filter or drill-down in the dashboard becomes a DuckDB query running locally. For larger deployments, Rill also supports ClickHouse as an alternative OLAP engine, effectively letting a project scale from a laptop prototype to a much larger production dataset without rewriting the metrics layer.
Copy code
# rill metrics view definition (simplified)
type: metrics_view
model: orders_model
dimensions:
- column: country
measures:
- name: total_revenue
expression: SUM(order_total)
Copy code
-- A Rill model, just a DuckDB SQL query
SELECT
order_id,
country,
order_total
FROM read_parquet('s3://bucket/orders/*.parquet')
Where it fits
Rill sits closer to the data than a traditional dashboarding tool that only queries an existing warehouse — it does its own ingestion and transformation, then exposes a metrics layer that both dashboards and, increasingly, AI agents can query consistently. For datasets under roughly 50GB, keeping data in DuckDB is Rill's recommended default; beyond that, teams typically move to the ClickHouse engine option.
Related terms
ClickHouse is an open-source, column-oriented OLAP database built for fast analytical queries over very large datasets.
Semantic layer →A semantic layer is a layer between raw data and end users that defines business metrics, dimensions, and relationships once, so that different tools and teams query consistent, agreed-upon definitions instead of re-deriving them independently.
data build tool (dbt) →dbt is an open-source command-line tool that enables data analysts and engineers to transform data in their warehouses more effectively.
dashboard →A dashboard is a visual display of key metrics, data points, and analytics that provides a quick overview of an organization's performance or a specific…
Data transformation →Data transformation is the process of converting data from its raw, source format into a structured form suited to analysis — through operations like cleaning, joining, aggregating, and reshaping.
dbt →dbt (data build tool) is an open-source command-line tool that enables data analysts and engineers to transform data in their warehouses more effectively.
FAQS
Yes, Rill Developer is open source. Rill Data also offers a managed cloud product for deploying and sharing Rill dashboards.
Rill's team chose DuckDB for its single-node analytical query speed, which lets dashboards feel instant while iterating locally on smaller-to-medium datasets, typically under about 50GB.
Yes. Rill also supports ClickHouse as an alternative OLAP engine for larger-scale or production deployments, while keeping the same metrics-as-code project structure.
