Valk Guard
Valk Guard is a free SQL linter for scanning raw SQL and application code before changes merge.
What Valk Guard is
Valk Guard is a free SQL linter for scanning raw SQL and application code before changes merge. It parses Go, Python, and C# source and derives SQL from supported ORM and query-builder patterns. The tool uses a PostgreSQL parser and does not support MySQL, SQLite, or other dialects. Nineteen rules cover query safety, schema drift, and query or schema validation. Integrations include Go database/sql and Goqu, Python SQLAlchemy, and C# EF Core. Scans require no database connection, which fits CI and pull request workflows. Findings can be emitted as terminal output, JSON, reviewdog rdjsonl, or SARIF for GitHub code scanning. A documented reviewdog workflow can post findings as GitHub pull-request comments. Linux, macOS, and Windows binaries are available, alongside a Go install option. Building from source requires Go 1.25.8 or later; Python and C# scans require Python 3.6+ and .NET SDK 8.0+. Valk Guard is Apache 2.0 licensed and supports configuration and CI/CD integration.
Good
- Scans without a database connection
- Includes 19 validation rules
- Supports CI/CD integration
- Outputs SARIF and reviewdog formats
- Provides Linux, macOS, and Windows binaries
Watch out
- Supports PostgreSQL only
- No automatic fixes
- No custom rules
- C# synthesis skips uncertain dynamic expressions
Who it suits
It suits development teams that review SQL safety in CI or pull requests, especially projects using PostgreSQL with the listed Go, Python, or C# integrations. It is less suitable for unsupported SQL dialects.
Verdict
Valk Guard provides database-free SQL analysis for CI and pull-request review, with multiple output formats and language integrations. PostgreSQL support and the absence of automatic fixes or custom rules define its boundaries.
The facts
Each one read from Valk Guard's own pages, with the date it was checked.
What it does
- Analysis
- It parses Go, Python, and C# source and synthesizes SQL from supported ORM and query-builder patterns.checked 7 Oct 2026
- Audience
- The README describes Valk Guard as built for CI and pull request review workflows.checked 7 Oct 2026
- CI output
- It can output terminal, JSON, reviewdog rdjsonl, and SARIF formats for GitHub code scanning.checked 7 Oct 2026
- Database connection
- Valk Guard requires no database connection to scan a project.checked 7 Oct 2026
- Database support
- It uses a PostgreSQL parser; MySQL, SQLite, and other dialects are not supported.checked 7 Oct 2026
- Installation
- The project provides prebuilt Linux, macOS, and Windows binaries and a Go install option.checked 7 Oct 2026
- Integrations
- It supports Go database/sql and Goqu, Python SQLAlchemy, and C# EF Core scanning.checked 7 Oct 2026
- License
- The repository identifies Valk Guard as Apache 2.0 licensed.checked 7 Oct 2026
- License and support
- The repository identifies its license as Apache 2.0 and links to contributing and security policy documents.checked 7 Oct 2026
- No database connection
- The project says scanning requires no database connection and runs in CI without database infrastructure.checked 7 Oct 2026
- Notable limitation
- C# query-builder synthesis covers deterministic query shapes and skips uncertain dynamic expressions.checked 7 Oct 2026
- Output formats
- Findings can be reported in terminal, JSON, rdjsonl, or SARIF formats.checked 7 Oct 2026
- PostgreSQL only
- It uses a PostgreSQL parser; MySQL, SQLite, and other dialects are not supported.checked 7 Oct 2026
- Pull request review
- The project documents a reviewdog workflow that posts findings as GitHub pull request comments.checked 7 Oct 2026
- Purpose
- Valk Guard is a SQL linter that scans raw SQL and application code to catch risky queries before they merge.checked 7 Oct 2026
- Requirements
- Building from source requires Go 1.25.8 or later; scanning Python files requires Python 3.6 or later, and scanning C# files requires .NET SDK 8.0 or later.checked 7 Oct 2026
- Rules
- It ships with 19 rules covering query safety, schema drift, and query/schema validation.checked 7 Oct 2026
- Security reporting
- The repository links to a security policy and vulnerability reporting route.checked 7 Oct 2026
Where it runs
- Platforms
- Prebuilt binaries are offered for Linux, macOS, and Windows, with amd64 and arm64 builds.checked 7 Oct 2026
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