Stefan Zhelev
Data Professional
phone
WhatsApp
PDF

Data Quality

Elementary is an open-source data observability tool that installs as a dbt package. It tests data quality, tracks freshness and volume, detects anomalies, and generates a static report — the trust layer for a dbt-native data platform.

image

Objective

Trust the data — automated tests, freshness and volume checks, anomaly detection, and schema-change tracking on top of the same dbt project the rest of the data stack already manages. For an AI-first stack, the additional requirement is that the trust layer must be code-and-config first: tests defined in YAML/SQL in the same repo agents already work in, no separate UI to drive.

Open Source Alternatives

Elementary — 9 / 10

dbt-native data observability. Installs as a dbt package and reads the same dbt_project.yml the rest of the stack already manages. Tests, freshness and volume checks, anomaly detection, and schema-change alerts live alongside the models they cover. The dashboard (“Elementary Report”) is a generated static site — a read-only artefact, not a UI that mutates state. Code-first, AI-agent-friendly, and the only OSS tool with first-class dbt integration in this category.

Great Expectations — 7 / 10

The historical leader in OSS data quality. Python-test-heavy model with a steep learning curve. Excellent for code-first teams that aren’t dbt-centric; weaker warehouse integration (ClickHouse is supported but second-class) and a much heavier operational surface than Elementary.

Soda Core — 7 / 10

YAML-defined data quality checks with a clean CLI. Decent dbt integration but lighter than Elementary. The right pick when the team wants explicit checks-as-code separately from dbt models rather than colocated with them.

dbt’s built-in tests — 6 / 10

The baseline. unique, not_null, accepted_values, relationships, plus custom singular tests. Sufficient for basic invariants; no anomaly detection, no freshness/volume tracking, no historical metadata. Elementary builds on top of this rather than replacing it.

re_data — 6 / 10

dbt-native data observability, alternative to Elementary with a smaller community and lower release cadence. Useful as a reference for the design space; not a recommendation today.

Pandera — 6 / 10

Statistical typing and validation for pandas/Polars DataFrames. Different audience (code-level data validation, not warehouse data quality). Useful complement, not a replacement.

Managed SaaS Alternatives

Elementary Cloud — 9 / 10

Hosted Elementary with team features, alerting, and a richer dashboard. Same technical model as OSS plus collaboration. Premium tier of the chosen tool.

Monte Carlo — 8 / 10

The SaaS leader for data observability — lineage, anomaly detection, incident management. Excellent UX and broad warehouse coverage. Premium pricing; mostly aligned with larger orgs.

Bigeye — 7 / 10

Managed data observability with strong anomaly detection. Premium SaaS.

Datafold — 7 / 10

Data diff and observability. Strong for column-level lineage and pre-merge change validation; narrower than Elementary or Monte Carlo for runtime observability.

Anomalo — 7 / 10

ML-driven anomaly detection on tables. Premium SaaS, narrower scope than Monte Carlo.

Soda Cloud — 7 / 10

Managed Soda with team UI and alerting. Same advantage profile as OSS Soda.

Datadog Data Streams Monitoring — 7 / 10

Data quality features bolted onto Datadog. Useful for teams already on Datadog; not a primary pick.

Scoring summary

Tool Score Type Best for
Elementary 9 OSS dbt-native data quality, AI-agent-friendly
Elementary Cloud 9 SaaS Managed Elementary
Monte Carlo 8 SaaS Enterprise data observability with lineage
Great Expectations 7 OSS Python-test-heavy data validation
Soda Core 7 OSS YAML checks-as-code
Bigeye 7 SaaS Managed anomaly detection
Datafold 7 SaaS Data diff + column lineage
Anomalo 7 SaaS ML-driven anomaly detection
Soda Cloud 7 SaaS Managed Soda
Datadog DSM 7 SaaS Data quality on Datadog
dbt built-in tests 6 OSS Basic invariants only
re_data 6 OSS dbt-native (smaller community)
Pandera 6 OSS Code-level DataFrame validation

Top in this category

Top OSS pick: Elementary. Top managed pick: Elementary Cloud or Monte Carlo.

For a dbt-native, AI-first data platform, Elementary is the right pick by structural alignment, not just feature comparison: tests and metadata live in the same dbt project agents already manipulate; the Elementary Report is a Git-tracked static artefact; nothing requires UI clicking to drive. Monte Carlo is the right pick when budget is available and the team prefers a fully managed observability surface with lineage out of the box.

Work Experience

Epic Data Operations 7 months
Octopyth Data Engineering and Operations 1 year 11 months
MiFinity Business Intellignece Manager (1 direct report) 7 months
Nexo Senior Data Engineer (2 direct reports) 1 year 10 months
Rank Interactive Senior Data Analyst 1 year 8 months
IBM Predictive Analytics and Reporting 1 year 1 month
Hewlett-Packard Service Level Management and Reporting 6 years 2 months