Linting

8Vast analyzes your code for errors, performance issues, security risks, and quality problems. It works on any language — Rust, TypeScript, Python, Go, Java, C, C++, and more.

8v lint .

No extra install. No plugins. Built into the 8v CLI. It also detects your existing tools (Clippy, ESLint, Ruff, mypy) and merges everything into one report.

Supported languages

Language	Built-in rules	External tools
Rust	156 rules (deep coverage)	Clippy, cargo check
TypeScript	3 rules + metrics	tsc, ESLint
Python	Metrics	Ruff, mypy
Go, Java, C, C++, ...	Metrics	—

For any language, you can also write custom rules in YAML to catch patterns specific to your project. See Custom Rules.

What it catches

• Error handling — swallowed errors, broken error chains, wrong log levels. No other linter catches these.
• Safety — panics in libraries, undocumented unsafe, blocking in async
• Performance — clones in loops, large futures, blocking I/O in async
• Security — SQL injection, command injection, hardcoded secrets
• Metrics — function length, nesting depth, cognitive complexity (configurable thresholds)
• Test quality — missing assertions, trivial assertions, ignored tests without reason

How to write rules

Approach	When to use	Requires
YAML	Pattern matching, metrics, most custom rules	No code — just a YAML file
Built-in	Common patterns — ship with 8Vast	Nothing — already there
Native Rust	Complex logic, cross-file analysis	Rust code

Most teams use YAML rules. They work on any language and need no code — describe the pattern you want to catch, and 8Vast finds it.

How it compares

	8Vast	Semgrep	ast-grep	Clippy
Languages	Any	30+	Any	Rust only
Custom rules	YAML + Rust	YAML	YAML	Compiler plugin
Error handling rules	Built-in	Write your own	Write your own	Partial
Metrics enforcement	Built-in	No	No	No
External tool integration	Yes	No	No	N/A
Requires install	No (part of 8v)	Yes	Yes	Yes

For a detailed comparison, see vast-lint vs Semgrep vs ast-grep.

Docs

• Getting Started — run your first lint and understand the output
• Configuration — customize thresholds, disable rules, configure external tools
• Custom Rules — write your own rules in YAML or native Rust
• Rules Reference — all built-in rules organized by category