Configuration

Strider reads project settings from one strict TOML file named strider.toml. Version 1 has one [checks] namespace for formatting, maintainability, and correctness diagnostics, while [formatter] controls rendered source.

version = 1
color = "auto"

[formatter]
print-width = 180
max-blank-lines = 1
existing-line-breaks = "structural-only"
alignment.declarations = true
excludes = ["internal/generated/**"]

[checks]
excludes = ["testdata/**"]
baseline = "strider-baseline.toml"
minimum-severity = "warning"

[checks.rules.format]
severity = "warning"

[checks.rules.no-init]
severity = "none"

[checks.rules.file-length-limit]
severity = "error"
max-lines = 800
excludes = ["cmd/migrations/**"]

[checks.rules.possible-nil-dereference]
severity = "error"

Only settings that differ from Strider’s defaults are required.

Discovery

Without a global option, Strider starts in the current working directory and looks for strider.toml. If it is absent, Strider checks each parent directory up to the filesystem root. The nearest file wins, so commands launched from a nested package still use the repository policy.

Choose a file explicitly when testing another policy:

strider --config configs/strict.toml check ./...

Temporarily use only built-in defaults:

strider --no-config check ./...

--config and --no-config are global options, so they must appear before the command. They are mutually exclusive. An explicit path must exist; automatic discovery quietly falls back to defaults when no file exists.

Version and strict validation

The configuration version is 1; new files should declare it explicitly. There is no alternate or legacy schema.

Strider rejects malformed TOML, unsupported versions, unknown section keys, unknown check names, invalid severities, and formatter values outside their accepted ranges. A configuration error exits with status 2 before source files are changed or diagnostics are reported.

This strictness catches misspellings such as severty = "error" instead of silently running with a different policy.

Strider does not currently support inherited configuration, environment variable overrides, user-wide configuration, or a published JSON Schema.

Precedence

Effective behavior is assembled in this order:

1. Built-in defaults.
2. The discovered or explicitly selected strider.toml.
3. Command-line selection, severity, and baseline flags.

check --only CODE narrows the catalog but still applies configured severity and per-rule exclusions. To investigate checks configured with severity = "none", use --minimum-severity none, optionally together with --only.

An explicit --baseline PATH overrides [checks].baseline. The global --color option similarly overrides the top-level color setting.

Terminal output

The top-level color setting controls ANSI styling for human-readable output.

Setting	Type	Default	Accepted values and effect
color	string	"auto"	"auto" uses color for terminals, "always" forces it, and "never" disables it.

Strider applies semantic colors throughout its human interface: errors are red, warnings yellow, notes blue, and check codes, paths, source gutters, commands, and options use xterm color 2. Successful output, suggested remedies, and diff additions use xterm color 10; diff removals remain red. JSON and formatter standard-input source are never styled.

For one run, place the global override before the command:

strider --color always check ./...
strider --color never fmt ./...

Strider also honors the NO_COLOR and FORCE_COLOR conventions. A non-empty FORCE_COLOR has precedence over NO_COLOR and the configured or CLI mode; FORCE_COLOR=0 explicitly disables color.

Path patterns

excludes is supported by the formatter, the unified check runner, and every individual check. Paths are evaluated relative to the directory containing strider.toml.

• A plain path such as testdata or internal/generated matches that path and everything below it.
• A glob may use *, ?, character classes such as [a-z], and ** for recursive directory matching.
• Paths use slash-separated project-relative spelling on every operating system.

[formatter]
excludes = ["vendor-tools", "**/*.generated.go"]

[checks]
excludes = ["testdata/**"]

[checks.rules.package-comments]
excludes = ["cmd/**", "examples/**"]

[checks].excludes removes matching files from the entire diagnostic run. Per-check exclusions disable only that code. [formatter].excludes applies to the fmt command and to code format; it does not apply to formatter stdin, which has no discovery pass.

Formatter

Formatter settings live under [formatter].

Setting	Type	Default	Accepted values and effect
print-width	integer	180	Wrap target from 40 through 500 columns.
max-blank-lines	integer	1	Preserve at most one consecutive empty line. Version 1 requires 1 for gofmt stability.
existing-line-breaks	string	"structural-only"	Preserve structural blank separators and comment placement while reflowing ordinary source breaks. Version 1 accepts only "structural-only".
alignment.declarations	boolean	true	Align declaration columns through the required gofmt-compatible final pass. Version 1 requires true.
excludes	string list	[]	Plain paths or globs skipped by filesystem formatting and the format check.

The formatter remains intentionally opinionated. Imports are sorted into standard-library, third-party, and current-module groups; indentation uses tabs; broken lists use trailing commas; top-level declarations use const, var, type, then func order; binary operators remain on the preceding line; and output has exactly one final newline. A whole-file strider:format-ignore directive is recognized only in comments before the package clause.

Checks

Tool-wide settings live under [checks].

Setting	Type	Default	Effect
excludes	string list	[]	Skip matching files for all checks.
baseline	string	unset	Apply this baseline unless the CLI overrides or ignores it. Relative paths resolve from strider.toml.
minimum-severity	string	"warning"	Run only checks whose effective severity is at least "none", "note", "warning", or "error".
rules	table	{}	Common configuration keyed by any registered check code.

All 207 checks are eligible. The default warning floor runs the 191 checks whose effective severity is warning or error. strider check --minimum-severity note also runs note checks, while strider check --minimum-severity none additionally runs checks configured with severity none.

Every code accepts the same two common options:

Setting	Type	Default	Effect
severity	string	Check default	Report as "none", "note", "warning", or "error"; "none" suppresses the check at ordinary minimum severities. Every reported finding still exits 1.
excludes	string list	[]	Skip only this check on matching paths.

[checks.rules.format]
severity = "warning"

[checks.rules.file-length-limit]
severity = "warning"
max-lines = 800
excludes = ["testdata/golden/**"]

[checks.rules.invalid-regexp]
severity = "none"

Eight checks accept additional behavioral options. A numeric value of 0 uses the built-in limit, except for file-length-limit, where 0 disables the check. Empty lists are meaningful: they allow all characters or block no imports.

Check	Setting	Type	Built-in behavior
banned-characters	characters	string list	Ban ᐸ and ᐳ; [] bans none.
file-length-limit	max-lines	integer	500; 0 disables the check.
function-length	max-lines, max-statements	integer	75 lines and 50 statements; 0 uses either built-in limit.
function-result-limit	max-results	integer	3; 0 uses the built-in limit.
imports-blocklist	blocked-imports	string list	[] blocks no imports.
max-parameters	max-parameters	integer	8; 0 uses the built-in limit.
max-public-structs	max-public-structs	integer	5; 0 uses the built-in limit.
interface-method-limit	max-methods	integer	10; 0 uses the built-in limit.

Each linked check page shows its complete TOML table and examples. Check-specific options are rejected on unrelated check codes.

Strider resolves selection and each rule’s severity before applying minimum-severity, using none < note < warning < error. A note promoted to error is therefore included in an error-only run; an error demoted to note is excluded from a warning-only run. A check set to none is omitted unless the minimum is explicitly lowered to none. Explicit --only selection still respects the minimum. Override it for one command with --minimum-severity.

Strider may satisfy selected checks from source text, syntax, type information, or control-flow data. These capabilities are internal scheduling details: they are not configuration categories, and Strider prepares only the union required by the selected codes.

Baseline path

Configure one baseline for the unified diagnostic set:

[checks]
baseline = "strider-baseline.toml"

Relative baseline paths resolve from the configuration directory, not the shell’s current directory. The format check is never stored in a baseline. See Baselines for generation, matching, pruning, and CI adoption.

Source directives

Configuration controls project policy; source directives record local exceptions. See Suppress checks for inline, file-level, and formatter directives.