The standing crew: built-in linters

Builtins be the standing crew who come with the ship: reusable Pkl step definitions for linters, formatters, and hk's own utilities. Between them they bring file patterns, check and fix commands, and optimizations such as diff output.

Bring the tools aboard separately. A builtin calls on executables from yer environment; it does not install them. Provision them with yer project's package manager or with mise, the quartermaster.

Muster a builtin

pkl

amends "package://github.com/jdx/hk/releases/download/v2.5.0/hk@2.5.0#/Config.pkl"
import "package://github.com/jdx/hk/releases/download/v2.5.0/hk@2.5.0#/Builtins.pkl"

hooks {
  ["check"] {
    steps {
      ["prettier"] = Builtins.prettier
      ["eslint"] = Builtins.eslint
    }
  }
}

Builtins.prettier is the Pkl property name, the name the hand goes by on the roster. The step name, "prettier", is yer own label for that hand, the one ye name in calls such as hk check --step prettier.

Aye, and keep the schema and Builtins imports on the same version. The roster below describes the version of the source this website was built from; an older pinned package may differ.

Refit a builtin

Amend a builtin to keep its defaults while ye change particular properties:

pkl

["prettier"] = (Builtins.prettier) {
  glob = List("*.js", "*.ts", "*.json")
  exclude = List("**/generated/**")
  batch = false
}

Mind this: a property assignment replaces that property whole. If ye override glob or exclude, include every pattern ye want to keep.

Use dependencies to set the order the hands work in, and profiles (the ship's watches) for optional checks:

pkl

["prettier"] = (Builtins.prettier) {
  depends = "eslint"
}
["mypy"] = (Builtins.mypy) {
  profiles = List("types")
}

Run the type checker by calling its watch: hk check --profile types. See the configuration charts for groups, workspaces, and command templates.

Utilities hk carries aboard

Hands such as Builtins.trailing_whitespace, Builtins.newlines, and Builtins.check_merge_conflict call on hk util commands. These sail with hk itself and need no separate linter executable.

Tools on hand

A builtin charts how hk calls a tool; it does not install that tool. The executable the builtin uses must be on PATH, or the step must use a prefix that resolves it.

With the standing order HK_MISE=1, hk resolves the quartermaster's mise environment for the step's own directory, so tools declared in a subproject's mise.toml are on hand without a prefix. For a Node tool installed locally by aube, prefix its builtin with aube exec:

pkl

["eslint"] = (Builtins.eslint) {
  prefix = List("aube", "exec")
}

Mind ye, use an argv list for builtins backed by structured commands. A string prefix such as "aube exec" or "mise x --" cannot be combined with those commands.

The crew roster

The roster below is generated from the builtin definitions themselves, so it stays in plain English. Each entry gives the exact Pkl property to call the hand by. Look to the source definitions for more options and tests.

.NET

`dotnet-format`

Pkl: Builtins.dotnet_format

Format C# and Visual Basic with the .NET SDK

Files: **/*.cs, **/*.vb
Check: dotnet format --verify-no-changes --include {{files}}
Fix: dotnet format --include {{files}}
Options: exclusive = true

AsciiDoc

`asciidoctor`

Pkl: Builtins.asciidoctor

AsciiDoc syntax validator and processor

Files: asciidoc files
Check: asciidoctor --failure-level=WARNING --out-file=/dev/null {{files}}

Build Systems

`buildifier-format`

Pkl: Builtins.buildifier_format

Formatter for Bazel BUILD, WORKSPACE, and Starlark files

Files: **/BUILD, **/BUILD.bazel, WORKSPACE, WORKSPACE.bazel, MODULE.bazel, **/*.bzl, **/*.star, **/*.sky
Check: buildifier -mode=check {{files}}
Check (diff): hk util format-diff {{files}} -- buildifier '-path={}'
Fix: buildifier {{files}}

`buildifier-lint`

Pkl: Builtins.buildifier_lint

Linter for Bazel BUILD, WORKSPACE, and Starlark files

Files: **/BUILD, **/BUILD.bazel, WORKSPACE, WORKSPACE.bazel, MODULE.bazel, **/*.bzl, **/*.star, **/*.sky
Check: buildifier -mode=check -lint=warn {{files}}
Fix: buildifier -lint=fix {{files}}

CSS

`stylelint`

Pkl: Builtins.stylelint

CSS linter

Files: **/*.css, **/*.scss, **/*.sass, **/*.less
Check: stylelint {{files}}
Fix: stylelint --fix {{files}}

Configuration

`sort-package-json`

Pkl: Builtins.sort_package_json

Sort package.json keys

Files: **/package.json
Check: sort-package-json --check {{files}}
Fix: sort-package-json {{files}}

Data Formats

`buf-format`

Pkl: Builtins.buf_format

Protocol Buffers formatter

Files: **/*.proto
Check (diff): buf format {{workspace}} --diff --exit-code
Fix: buf format {{workspace}} --write
Options: workspace_indicator = "buf.yaml"

`buf-lint`

Pkl: Builtins.buf_lint

Protocol Buffers linter

Files: **/*.proto
Check: buf lint {{workspace}}
Options: workspace_indicator = "buf.yaml"

`jq`

Pkl: Builtins.jq

JSON processor

Files: **/*.json

Check (diff):

failed=0
broken=0
trap 'rm -f "$out" "$patch" "$new"' EXIT
trap 'exit 2' HUP INT TERM
out=$(mktemp) && patch=$(mktemp) && new=$(mktemp) || exit 2
n=0
set --
for f in {{ files }}; do
n=$((n + 1))
set -- "$@" --rawfile "f$n" "$f"
done
# Each file's output follows \u001e, which formatted JSON never
# contains, and is \u001f if jq cannot parse the file.
todo=all
if [ "$n" -gt 1 ] && jq -n -j -S --argjson n "$n" "$@" '
range(1; $n + 1) as $i | "\u001e", ($ARGS.named["f\($i)"]
| try (fromjson | if type == "string" then tojson else . end, "\n") catch "\u001f")
' > "$new" 2>/dev/null; then
todo=$(jq -n -r --argjson n "$n" --rawfile new "$new" "$@" '
($new | split("\u001e")) as $new
| [range(1; $n + 1) | select($new[.] != $ARGS.named["f\(.)"]
or ($new[.] | contains("\u001f") or contains("\ufffd"))) | tostring]
| " " + join(" ") + " "
' 2>/dev/null) || todo=all
fi
i=0
for f in {{ files }}; do
i=$((i + 1))
case $todo in
all | *" $i "*) ;;
*) continue ;;
esac
if jq -S . "$f" > "$out"; then
# hk runs this with `set -e`, so take diff's status through `||`.
status=0
diff -u -L "a/$f" -L "b/$f" "$f" "$out" >> "$patch" || status=$?
case $status in
0) ;;
1) failed=1 ;;
*) broken=1 ;;
esac
else
broken=1
fi
done
# When a file failed to parse or diff, print no patch: hk then runs the
# fixer on every file, and the fixer reports the error.
[ "$broken" = 1 ] && exit 1
cat "$patch" || exit 2
exit $failed

Fix:

failed=0
tmp=
trap 'rm -f "$tmp"' EXIT
trap 'exit 2' HUP INT TERM
for f in {{ files }}; do
# Write a copy beside the file, with its permissions, then rename it
# over the file, so a failed write never truncates the original. A
# file that is already formatted is left alone, links and all.
tmp=$(mktemp "$f.XXXXXX") &&
cp -p "$f" "$tmp" &&
jq -S . "$f" > "$tmp" &&
{ cmp -s "$f" "$tmp" || mv "$tmp" "$f"; } || failed=1
rm -f "$tmp"
tmp=
done
exit $failed

Options: batch = true

`sql-fluff`

Pkl: Builtins.sql_fluff

SQL linter and formatter

Files: **/*.sql
Check: sqlfluff lint {{files}}
Fix: sqlfluff fix {{files}}

`taplo`

Pkl: Builtins.taplo

TOML linter

Files: **/*.toml
Check: taplo lint {{files}}

`taplo-format`

Pkl: Builtins.taplo_format

TOML formatter

Files: **/*.toml
Check: taplo format --check --diff {{files}}

Check (diff):

# Windows: nothing runs
# other platforms:
set --
for f in {{ files }}; do
taplo format --check --colors never "$f" > /dev/null 2>&1 || set -- "$@" "$f"
done
[ $# -eq 0 ] && exit 0
hk util format-diff "$@" -- taplo format --colors never --stdin-filepath {} -

Fix: taplo format {{files}}

`tombi`

Pkl: Builtins.tombi

TOML linter

Files: **/*.toml
Check: tombi lint --quiet {{files}}

`tombi-format`

Pkl: Builtins.tombi_format

TOML formatter

Files: **/*.toml
Check: tombi format --quiet --check --diff {{files}}
Check (diff): hk util format-diff {{files}} -- tombi format --quiet --stdin-filename '{}' -
Fix: tombi format --quiet {{files}}

`xmllint`

Pkl: Builtins.xmllint

XML validator

Files: **/*.xml
Check: xmllint --noout {{files}}

`yamlfmt`

Pkl: Builtins.yamlfmt

YAML formatter

Files: **/*.yml, **/*.yaml
Check: yamlfmt -lint {{files}}

Check (diff):

# Windows: nothing runs
# other platforms:
# If yamlfmt fails, print no patch: hk runs the fixer, which reports it.
list=$(yamlfmt -dry -quiet {{ files }}) || exit $?
set --
# After a heading, `-dry -quiet` lists the files that would change.
# Anything else it lists, such as part of a name containing a newline,
# prints no patch, so hk runs the fixer instead of skipping the file.
# The here-document expands `$list` once; the names in it are not
# expanded again, so `$(...)` in a name is just text.
while IFS= read -r f; do
case $f in
'' | 'The following files would be formatted:') continue ;;
esac
if [ ! -f "$f" ]; then
echo "yamlfmt listed a file that does not exist: $f" >&2
exit 1
fi
set -- "$@" "$f"
done <<EOF
$list
EOF
[ $# -eq 0 ] && exit 0
hk util format-diff "$@" -- yamlfmt -in

Fix: yamlfmt {{files}}

`yamllint`

Pkl: Builtins.yamllint

YAML linter

Files: **/*.yml, **/*.yaml
Check: yamllint --strict {{files}}

`yq`

Pkl: Builtins.yq

YAML processor

Files: **/*.yaml, **/*.yml

Check (diff):

failed=0
broken=0
trap 'rm -rf "$out" "$patch" "$split"' EXIT
trap 'exit 2' HUP INT TERM
out=$(mktemp) && patch=$(mktemp) && split=$(mktemp -d) || exit 2
set --
for f in {{ files }}; do
case $f in
*.[yY][aA][mM][lL] | *.[yY][mM][lL]) set -- "$@" "$f" ;;
esac
done
fast=0
if [ $# -gt 1 ] && YQ_SPLIT="$split/" yq -P -N -s 'strenv(YQ_SPLIT) +
(file_index | tostring) + "-" + (document_index | tostring)' "$@" > /dev/null 2>&1; then
fast=1
fi
i=0
for f in {{ files }}; do
new=
case $f in
*.[yY][aA][mM][lL] | *.[yY][mM][lL])
new="$split/$i-0.yml"
i=$((i + 1))
;;
esac
if [ "$fast" = 1 ] && [ -n "$new" ] && [ -f "$new" ] &&
[ ! -e "${new%-0.yml}-1.yml" ] && cmp -s "$f" "$new"; then
continue
fi
if yq -P "$f" > "$out"; then
# hk runs this with `set -e`, so take diff's status through `||`.
status=0
diff -u -L "a/$f" -L "b/$f" "$f" "$out" >> "$patch" || status=$?
case $status in
0) ;;
1) failed=1 ;;
*) broken=1 ;;
esac
else
broken=1
fi
done
# When a file failed to parse or diff, print no patch: hk then runs the
# fixer on every file, and the fixer reports the error.
[ "$broken" = 1 ] && exit 1
cat "$patch" || exit 2
exit $failed

Fix:

failed=0
for f in {{ files }}; do
yq -iP "$f" || failed=1
done
exit $failed

Options: batch = true

EditorConfig

`editorconfig-checker`

Pkl: Builtins.editorconfig_checker

Validate files against EditorConfig rules

Files: text files
Check: editorconfig-checker {{files}}
Fix: editorconfig-checker --fix {{files}}

Elixir

`mix-compile`

Pkl: Builtins.mix_compile

Compile Elixir with Mix

Files: **/*.ex
Check: mix compile --warnings-as-errors --strict-errors {{files}}
Options: exclude = List("deps/**/*")

`mix-fmt`

Pkl: Builtins.mix_fmt

Format Elixir with Mix

Files: **/*.ex, **/*.exs
Check: mix format --check-formatted {{files}}
Fix: mix format {{files}}
Options: exclude = List("deps/**/*")

`mix-test`

Pkl: Builtins.mix_test

Test Elixir with Mix

Files: **/*.ex, **/*.exs
Check: mix test --warnings-as-errors {{files}}
Options: exclude = List("deps/**/*")

Go

`err-check`

Pkl: Builtins.err_check

Error handling checker

Files: **/*.go
Check: errcheck ./...
Options: workspace_indicator = "go.mod", dir = "{{workspace}}"

`go-fix`

Pkl: Builtins.go_fix

Go modernizer (requires Go 1.26+)

Files: **/*.go
Check (diff): go fix -diff ./...
Fix: go fix ./...
Options: workspace_indicator = "go.mod", dir = "{{workspace}}"

`go-fmt`

Pkl: Builtins.go_fmt

Go formatter

Files: **/*.go

Check (diff):

DIFF=$(gofmt -s -d {{files}})
if [ -n "$DIFF" ]; then
echo "$DIFF"
exit 1
fi

Check (list files):

FILES=$(gofmt -s -l {{files}})
if [ -n "$FILES" ]; then
echo "$FILES"
exit 1
fi

Fix: gofmt -s -w {{files}}

`go-fumpt`

Pkl: Builtins.go_fumpt

Strict Go formatter

Files: **/*.go
Check (diff): gofumpt -d {{files}}

Check (list files):

FILES=$(gofumpt -l {{files}})
if [ -n "$FILES" ]; then
echo "$FILES"
exit 1
fi

Fix: gofumpt -w {{files}}

`go-imports`

Pkl: Builtins.go_imports

Go import management

Files: **/*.go

Check (diff):

DIFF=$(goimports -d {{files}})
if [ -n "$DIFF" ]; then
echo "$DIFF"
exit 1
fi

Check (list files):

FILES=$(goimports -l {{files}})
if [ -n "$FILES" ]; then
echo "$FILES"
exit 1
fi

Fix: goimports -w {{files}}

`go-lines`

Pkl: Builtins.go_lines

Long line fixer

Files: **/*.go
Check (diff): hk util format-diff {{files}} -- golines
Fix: golines -w {{files}}

`go-sec`

Pkl: Builtins.go_sec

Security scanner

Files: **/*.go
Check: gosec ./...
Options: workspace_indicator = "go.mod", dir = "{{workspace}}"

`go-vet`

Pkl: Builtins.go_vet

Go code vetting

Files: **/*.go
Check: go vet ./...
Options: workspace_indicator = "go.mod", dir = "{{workspace}}"

`go-vuln-check`

Pkl: Builtins.go_vuln_check

Vulnerability scanner

Files: **/*.go
Check: govulncheck ./...
Options: workspace_indicator = "go.mod", dir = "{{workspace}}"

`golangci-lint`

Pkl: Builtins.golangci_lint

Go meta-linter

Files: **/*.go
Check: golangci-lint run --fix=false ./...
Fix: golangci-lint run --fix ./...
Options: workspace_indicator = "go.mod", dir = "{{workspace}}"

`golangci-lint-fmt`

Pkl: Builtins.golangci_lint_fmt

Go formatter (part of golangci-lint)

Files: **/*.go
Check (diff): golangci-lint fmt --diff {{files}}
Fix: golangci-lint fmt {{files}}

`gomod-tidy`

Pkl: Builtins.gomod_tidy

Go module maintenance

Files: **/*.go, **/go.mod, **/go.sum
Check (diff): go mod tidy -diff
Fix: go mod tidy
Options: workspace_indicator = "go.mod", dir = "{{workspace}}", stage = List("go.mod", "go.sum")

`revive`

Pkl: Builtins.revive

Fast Go linter

Files: **/*.go
Check: revive -set_exit_status ./...
Options: workspace_indicator = "go.mod", dir = "{{workspace}}"

`staticcheck`

Pkl: Builtins.staticcheck

Go static analysis

Files: **/*.go
Check: staticcheck ./...
Options: workspace_indicator = "go.mod", dir = "{{workspace}}"

Infrastructure

`actionlint`

Pkl: Builtins.actionlint

GitHub Actions workflow linter

Files: .github/workflows/*.yml, .github/workflows/*.yaml
Check: actionlint {{files}}
Options: batch = true

`dclint`

Pkl: Builtins.dclint

Docker Compose linter

Files: **/compose*.yml, **/compose*.yaml, **/docker-compose*.yml, **/docker-compose*.yaml
Check: dclint {{files}}
Fix: dclint --fix {{files}}
Options: batch = true

`droast`

Pkl: Builtins.droast

Dockerfile linter for security, layer hygiene, and best-practice violations

Files: **/Dockerfile, **/Dockerfile.*, **/*.Dockerfile, **/*.dockerfile, **/Containerfile, **/Containerfile.*
Check: droast {{files}}
Fix: droast --fix {{files}}

`ghalint-action`

Pkl: Builtins.ghalint_action

GitHub Actions action linter

Files: **/action.* that are yaml files
Check: ghalint run-action {{files}}

`ghalint-workflow`

Pkl: Builtins.ghalint_workflow

GitHub Actions workflow linter

Files: .github/workflows/* that are yaml files
Check: ghalint run

`hadolint`

Pkl: Builtins.hadolint

Dockerfile linter

Files: **/Dockerfile*
Check: hadolint {{files}}

`hclfmt`

Pkl: Builtins.hclfmt

Hashicorp's hclfmt

Files: **/*.hcl
Fix: hclfmt -w {{files}}

`jactionlint`

Pkl: Builtins.jactionlint

GitHub Actions workflow linter (jdx/jactionlint, a maintained actionlint fork)

Files: .github/workflows/*.yml, .github/workflows/*.yaml
Check: jactionlint {{files}}
Options: batch = true

`kube-linter`

Pkl: Builtins.kube_linter

Check Kubernetes manifests for security and reliability issues

Files: **/k8s/**/*.yaml, **/k8s/**/*.yml, **/kubernetes/**/*.yaml, **/kubernetes/**/*.yml, **/manifests/**/*.yaml, **/manifests/**/*.yml, **/deploy/**/*.yaml, **/deploy/**/*.yml, **/deployments/**/*.yaml, **/deployments/**/*.yml
Check: kube-linter lint --fail-if-no-objects-found {{files}}
Options: exclude = List("**/templates/**", "**/values.yaml", "**/values.yml", "**/values-*.yaml", "**/values-*.yml", "**/kustomization.yaml", "**/kustomization.yml")

`kubeconform`

Pkl: Builtins.kubeconform

Kubernetes manifest validator

Files: **/k8s/**/*.yaml, **/k8s/**/*.yml, **/kubernetes/**/*.yaml, **/kubernetes/**/*.yml, **/manifests/**/*.yaml, **/manifests/**/*.yml, **/deploy/**/*.yaml, **/deploy/**/*.yml, **/deployments/**/*.yaml, **/deployments/**/*.yml
Check: kubeconform -summary -strict -ignore-missing-schemas {{files}}
Options: exclude = List("**/templates/**", "**/values.yaml", "**/values.yml", "**/kustomization.yaml", "**/kustomization.yml")

`mise`

Pkl: Builtins.mise

mise-en-place's built-in formatter and linter

Files: mise.toml, mise.*.toml, .mise.toml, .mise.*.toml, mise/config.toml, mise/config.*.toml, .mise/config.toml, .mise/config.*.toml, .config/mise.toml, .config/mise.*.toml, .config/mise/config.toml, .config/mise/config.*.toml, .config/mise/mise.toml, .config/mise/mise.*.toml, .config/mise/conf.d/*.toml
Check: mise fmt --check
Fix: mise fmt

`pinact`

Pkl: Builtins.pinact

Pin GitHub Actions to commit SHA for security

Files: .github/workflows/*, **/action.* that are yaml files
Check: pinact run --verify-comment --check {{files}}
Check (diff): hk util sarif-diff -- pinact run --verify-comment --check --format sarif {{files}}
Fix: pinact run --verify-comment {{files}}

`pinact-update`

Pkl: Builtins.pinact_update

Pin GitHub Actions to update actions to latest versions

Files: .github/workflows/*, **/action.* that are yaml files
Check: pinact run --update --verify-comment --check {{files}}
Check (diff): hk util sarif-diff -- pinact run --update --verify-comment --check --format sarif {{files}}
Fix: pinact run --update --verify-comment {{files}}

`terraform`

Pkl: Builtins.terraform

Terraform formatter

Files: **/*.tf, **/*.tfvars, **/*.tftest.hcl
Check: terraform fmt -check {{files}}
Check (diff): hk util format-diff {{files}} -- terraform fmt -
Fix: terraform fmt {{files}}

`terraform-docs`

Pkl: Builtins.terraform_docs

Terraform module documentation generator

Files: **/*.tf, **/*.tofu, **/.terraform.lock.hcl

Check:

for f in {{ files }}; do dirname "$f"; done | sort -u | { code=0; while IFS= read -r dir; do
terraform-docs markdown table --output-check --output-file README.md --output-mode inject "$dir" || code=1
done; exit $code; }

Fix:

for f in {{ files }}; do dirname "$f"; done | sort -u | { code=0; while IFS= read -r dir; do
terraform-docs markdown table --output-file README.md --output-mode inject "$dir" || code=1
done; exit $code; }

Options: exclude = "**/.terraform/**"

`terraform-validate`

Pkl: Builtins.terraform_validate

Terraform configuration validator

Files: **/*.tf, **/*.tfvars, **/*.tf.json, **/*.tofu, **/.terraform.lock.hcl

Check:

for f in {{ files }}; do dirname "$f"; done | sort -u | { code=0; while IFS= read -r dir; do
terraform -chdir="$dir" validate && continue
terraform -chdir="$dir" init -backend=false -input=false > /dev/null || { code=1; continue; }
terraform -chdir="$dir" validate || code=1
done; exit $code; }

Options: exclude = "**/.terraform/**"

`terragrunt-hcl-fmt`

Pkl: Builtins.terragrunt_hcl_fmt

Terragrunt HCL formatter

Files: **/*.hcl

Check:

set --
for f in {{ files }}; do set -- "$@" "--filter=./$f"; done
if [ "$#" -eq 0 ]; then exit 0; fi
terragrunt hcl fmt --check --diff "$@"

Fix:

set --
for f in {{ files }}; do set -- "$@" "--filter=./$f"; done
if [ "$#" -eq 0 ]; then exit 0; fi
terragrunt hcl fmt "$@"

Options: exclude = List("**/.terraform/**", "**/.terragrunt-cache/**")

`terragrunt-hcl-validate`

Pkl: Builtins.terragrunt_hcl_validate

Terragrunt HCL validator

Files: **/*.hcl

Check:

set --
for f in {{ files }}; do
case "$f" in */*) d="./${f%/*}" ;; *) d="." ;; esac
set -- "$@" "--filter=$d" "--filter=reading=./$f"
done
if [ "$#" -eq 0 ]; then exit 0; fi
terragrunt hcl validate --show-config-path --log-level error "$@"

Options: exclude = List("**/.terraform/**", "**/.terragrunt-cache/**")

`tf-lint`

Pkl: Builtins.tf_lint

Terraform linter

Files: **/*.tf, **/*.tfvars, **/*.tofu

Check:

for f in {{ files }}; do dirname "$f"; done | sort -u | { code=0; while IFS= read -r dir; do
tflint --chdir="$dir" || code=1
done; exit $code; }

Fix:

for f in {{ files }}; do dirname "$f"; done | sort -u | { code=0; while IFS= read -r dir; do
tflint --chdir="$dir" --fix || tflint --chdir="$dir" || code=1
done; exit $code; }

Options: exclude = "**/.terraform/**"

`tofu`

Pkl: Builtins.tofu

OpenTofu formatter

Files: **/*.tf, **/*.tfvars, **/*.tftest.hcl
Check: tofu fmt -check {{files}}
Check (diff): hk util format-diff {{files}} -- tofu fmt -
Fix: tofu fmt {{files}}

`zizmor`

Pkl: Builtins.zizmor

GitHub Actions security static analysis tool

Files: .github/workflows/*.yml, .github/workflows/*.yaml, .github/dependabot.yml, **/action.yml, **/action.yaml
Check: zizmor --no-progress {{files}}
Fix: zizmor --no-progress --fix {{files}}

Java

`google-java-format`

Pkl: Builtins.google_java_format

Google Java Format

Files: **/*.java
Check: google-java-format --dry-run --set-exit-if-changed {{files}}
Check (list files): google-java-format --dry-run {{files}}
Fix: google-java-format --replace {{files}}

JavaScript/TypeScript

`biome`

Pkl: Builtins.biome

Fast formatter and linter

Files: **/*.js, **/*.jsx, **/*.ts, **/*.tsx, **/*.json
Check: biome check --no-errors-on-unmatched {{files}}
Fix: biome check --write --no-errors-on-unmatched {{files}}

`deno`

Pkl: Builtins.deno

Deno formatter

Files: **/*.js, **/*.jsx, **/*.ts, **/*.tsx
Check: deno fmt --check {{files}}
Fix: deno fmt {{files}}

`deno-check`

Pkl: Builtins.deno_check

Deno type checker

Files: **/*.js, **/*.jsx, **/*.ts, **/*.tsx
Check: deno check {{files}}

`eslint`

Pkl: Builtins.eslint

Pluggable JavaScript linter

Files: **/*.js, **/*.jsx, **/*.ts, **/*.tsx
Check: eslint {{files}}
Fix: eslint --fix {{files}}
Options: batch = true

`knip`

Pkl: Builtins.knip

Find unused files, dependencies, and exports

Files: javascript, typescript files
Check: knip --no-progress --directory {{workspace}}
Fix: knip --fix --no-progress --directory {{workspace}}
Options: workspace_indicator = "package.json"

`ox-lint`

Pkl: Builtins.ox_lint

Oxidation compiler linter

Files: **/*.js, **/*.mjs, **/*.cjs, **/*.ts, **/*.mts, **/*.cts, **/*.jsx, **/*.tsx, **/*.vue, **/*.svelte, **/*.astro
Check: oxlint --deny-warnings {{files}}
Fix: oxlint --deny-warnings --fix {{files}}

`oxfmt`

Pkl: Builtins.oxfmt

Fast Rust-powered code formatter (Prettier compatible)

Files: **/*.js, **/*.mjs, **/*.cjs, **/*.ts, **/*.mts, **/*.cts, **/*.jsx, **/*.tsx, **/*.mdx, **/*.vue, **/*.json, **/*.jsonc, **/*.json5, **/*.yaml, **/*.yml, **/*.toml, **/*.md, **/*.markdown, **/*.html, **/*.htm, **/*.css, **/*.scss, **/*.less, **/*.graphql, **/*.gql, **/*.handlebars, **/*.hbs
Check: oxfmt --check --no-error-on-unmatched-pattern {{files}}
Check (diff): hk util format-diff {{files}} -- oxfmt --stdin-filepath '{}'
Fix: oxfmt --write --no-error-on-unmatched-pattern {{files}}

`prettier`

Pkl: Builtins.prettier

Opinionated code formatter

Files: **/*.js, **/*.jsx, **/*.mjs, **/*.cjs, **/*.ts, **/*.tsx, **/*.mts, **/*.cts, **/*.css, **/*.scss, **/*.less, **/*.html, **/*.json, **/*.json5, **/*.jsonc, **/*.yaml, **/*.yml, **/*.markdown, **/*.markdown.mdx, **/*.md, **/*.graphql, **/*.handlebars, **/*.svelte, **/*.astro, **/*.htmlangular, **/*.vue
Check: prettier --check {{files}}
Check (list files): prettier --list-different {{files}}
Fix: prettier --write {{files}}
Options: batch = true

`sherif`

Pkl: Builtins.sherif

Opinionated, zero-config linter for TypeScript & JavaScript monorepos

Files: **/package.json, **/pnpm-workspace.yaml
Check: sherif
Fix: sherif --fix --no-install

`standard-js`

Pkl: Builtins.standard_js

JavaScript Standard Style

Files: **/*.js, **/*.jsx, **/*.ts, **/*.tsx
Check: standard {{files}}
Fix: standard --fix {{files}}

`tsc`

Pkl: Builtins.tsc

TypeScript type checker

Files: **/*.ts, **/*.tsx
Check: tsc --noEmit -p {{workspace_indicator}}
Options: workspace_indicator = "tsconfig.json"

`tsserver`

Pkl: Builtins.tsserver

TypeScript language server diagnostics

Files: **/*.ts, **/*.tsx
Check: tsc-files --noEmit {{files}}

`vp-check`

Pkl: Builtins.vp_check

Formats, lints, and type checks code together

Files: **/*.js, **/*.mjs, **/*.cjs, **/*.ts, **/*.mts, **/*.cts, **/*.jsx, **/*.tsx, **/*.mdx, **/*.vue, **/*.svelte, **/*.astro, **/*.json, **/*.jsonc, **/*.json5, **/*.yaml, **/*.yml, **/*.md, **/*.markdown, **/*.html, **/*.htm, **/*.css, **/*.scss, **/*.less, **/*.graphql, **/*.gql, **/*.handlebars, **/*.hbs, **/*.toml
Check: vp check {{files}}
Fix: vp check --fix {{files}}
Options: workspace_indicator = "package.json"

`vp-fmt`

Pkl: Builtins.vp_fmt

Formats code with Oxfmt

Files: **/*.js, **/*.mjs, **/*.cjs, **/*.ts, **/*.mts, **/*.cts, **/*.jsx, **/*.tsx, **/*.mdx, **/*.vue, **/*.json, **/*.jsonc, **/*.json5, **/*.yaml, **/*.yml, **/*.toml, **/*.md, **/*.markdown, **/*.html, **/*.htm, **/*.css, **/*.scss, **/*.less, **/*.graphql, **/*.gql, **/*.handlebars, **/*.hbs
Check: vp fmt --check {{files}}
Check (list files): vp fmt --list-different {{files}}
Fix: vp fmt {{files}}
Options: workspace_indicator = "package.json"

`vp-lint`

Pkl: Builtins.vp_lint

Lints code with OxLint

Files: **/*.js, **/*.mjs, **/*.cjs, **/*.ts, **/*.mts, **/*.cts, **/*.jsx, **/*.tsx, **/*.mdx, **/*.vue, **/*.svelte, **/*.astro
Check: vp lint --deny-warnings {{files}}
Fix: vp lint --deny-warnings --fix {{files}}
Options: workspace_indicator = "package.json"

`xo`

Pkl: Builtins.xo

JavaScript/TypeScript linter with great defaults

Files: **/*.js, **/*.jsx, **/*.ts, **/*.tsx
Check: xo {{files}}
Fix: xo --fix {{files}}

Lua

`luacheck`

Pkl: Builtins.luacheck

Lua linter

Files: lua files
Check: luacheck {{files}}

`selene`

Pkl: Builtins.selene

Lua linter

Files: lua files
Check: selene {{files}}

`stylua`

Pkl: Builtins.stylua

Lua formatter

Files: lua files
Check: stylua --check {{files}}
Check (diff): hk util format-diff {{files}} -- stylua --stdin-filepath '{}' -
Fix: stylua {{files}}

Markdown

`contextlint`

Pkl: Builtins.contextlint

Rule-based linter for structured Markdown documents

Files: markdown files
Check: contextlint {{files}}
Options: workspace_indicator = "contextlint.config.json"

`mado`

Pkl: Builtins.mado

Fast Markdown linter (CommonMark/GFM)

Files: markdown files
Check: mado check {{files}}

`markdown-lint`

Pkl: Builtins.markdown_lint

Markdown linter

Files: **/*.md, **/*.markdown
Check: markdownlint {{files}}
Fix: markdownlint --fix {{files}}

`mdschema`

Pkl: Builtins.mdschema

Schema-based Markdown documentation validator

Files: markdown files
Check: mdschema check {{files}}
Options: workspace_indicator = ".mdschema.yml"

`rumdl`

Pkl: Builtins.rumdl

Markdown linter

Files: **/*.md, **/*.markdown
Check: rumdl check {{files}}
Check (diff): rumdl check --diff {{files}}
Fix: rumdl check --fix {{files}}
Options: check_after_diff = true

`rumdl-format`

Pkl: Builtins.rumdl_format

Markdown formatter

Files: **/*.md, **/*.markdown
Check (diff): rumdl fmt --check --diff {{files}}
Fix: rumdl fmt {{files}}

`ryl-markdown`

Pkl: Builtins.ryl_markdown

Lint YAML embedded in Markdown (front matter + fenced yaml blocks) with ryl

Files: markdown files
Check: ryl --markdown {{files}}
Check (diff): ryl --diff --markdown {{files}}
Check (list files): ryl --list-files --markdown {{files}}
Fix: ryl --fix --markdown {{files}}
Options: check_after_diff = true

Nix

`alejandra`

Pkl: Builtins.alejandra

Alternative Nix formatter

Files: **/*.nix
Check: alejandra --check {{files}}
Fix: alejandra {{files}}

`deadnix`

Pkl: Builtins.deadnix

Scan Nix files for dead code

Files: **/*.nix
Check: deadnix --fail {{files}}
Fix: deadnix --edit {{files}}

`nil`

Pkl: Builtins.nil

Nix Language server

Files: **/*.nix
Check: nil diagnostics --deny-warnings {{files}}

`nix-fmt`

Pkl: Builtins.nix_fmt

Nix formatter

Files: **/*.nix

Check:

# Windows: nothing runs
# other platforms:
nixfmt --check {{ files }}

Fix:

# Windows: nothing runs
# other platforms:
nixfmt {{ files }}

`nixf-diagnose`

Pkl: Builtins.nixf_diagnose

Nix linter based on libnixf

Files: **/*.nix
Check: nixf-diagnose {{files}}

`nixpkgs-format`

Pkl: Builtins.nixpkgs_format

Nixpkgs formatter

Files: **/*.nix
Check: nixpkgs-fmt --check {{files}}
Fix: nixpkgs-fmt {{files}}

Other Languages

`astro`

Pkl: Builtins.astro

Astro component checker

Files: **/*.astro
Check: astro check {{files}}

`clang-format`

Pkl: Builtins.clang_format

C/C++ formatter

Files: **/*.c, **/*.h, **/*.cpp, **/*.hpp, **/*.cc, **/*.hh, **/*.cxx, **/*.hxx
Check: clang-format --dry-run -Werror {{files}}
Fix: clang-format -i {{files}}

`cmake-format`

Pkl: Builtins.cmake_format

Source code formatter for cmake listfiles

Files: **/CMakeLists.txt, **/*.cmake
Check: cmake-format --check {{files}}
Fix: cmake-format --in-place {{files}}

`cpp-lint`

Pkl: Builtins.cpp_lint

C++ style checker

Files: **/*.c, **/*.h, **/*.cpp, **/*.hpp, **/*.cc, **/*.hh, **/*.cxx, **/*.hxx
Check: cpplint {{files}}

`dprint`

Pkl: Builtins.dprint

Pluggable code formatter

Files: text files
Check: dprint check --allow-no-files {{files}}
Check (list files): dprint check --allow-no-files --list-different {{files}}
Fix: dprint fmt --allow-no-files {{files}}

`ktlint`

Pkl: Builtins.ktlint

Kotlin linter and formatter

Files: **/*.kt
Check: ktlint {{files}}
Fix: ktlint -F {{files}}

`swiftlint`

Pkl: Builtins.swiftlint

Swift style and conventions

Files: **/*.swift
Check: swiftlint lint {{files}}
Fix: swiftlint --fix {{files}}

`vacuum`

Pkl: Builtins.vacuum

Fast OpenAPI linter

Files: **/*openapi*.yaml, **/*openapi*.yml, **/*openapi*.json, **/*swagger*.yaml, **/*swagger*.yml, **/*swagger*.json
Check: vacuum lint {{files}}
Fix: vacuum lint --fix {{files}}

PHP

`php-cs`

Pkl: Builtins.php_cs

PHP coding standards

Files: **/*.php
Check: phpcs {{files}}
Fix: phpcbf {{files}}

Package

`aqua-update-checksum`

Pkl: Builtins.aqua_update_checksum

create or update aqua checksums

Files: {aqua,.aqua}.{yml,yaml}, {aqua,.aqua}/**/*.{yml,yaml}, aqua-checksums.json, {aqua,.aqua}/aqua-checksums.json
Fix: aqua update-checksum --prune

Pkl

`pkl`

Pkl: Builtins.pkl

Pkl configuration language

Files: pkl files
Check: pkl eval {{files}} >/dev/null

`pkl-format`

Pkl: Builtins.pkl_format

Pkl formatter

Files: pkl files
Check (list files): pkl format --diff-name-only {{ files }}

Fix:

pkl format --write {{ files }}
code=$?
if [ $code -eq 11 ]; then
exit 0
else
exit $code
fi

Options: shell = "sh -c"

Python

`black`

Pkl: Builtins.black

Opinionated Python formatter

Files: **/*.py
Check: black --check {{files}}

Check (list files):

# Windows: nothing runs
# other platforms:
set -- {{ files }}
out=$(black --check "$@" 2>&1) && exit 0
status=$?
printf '%s\n' "$out" | while IFS= read -r line; do
case "$line" in
"would reformat "*) printf '%s\n' "${line#would reformat }" ;;
"error: cannot format "*)
  # The message after the path may contain ": ", so match the inputs.
  for f; do
  case "$line" in "error: cannot format $f: "*) printf '%s\n' "$f" ;; esac
  done
  ;;
esac
done
exit $status

Fix: black {{files}}

`flake8`

Pkl: Builtins.flake8

Python style guide enforcement

Files: **/*.py
Check: flake8 {{files}}

`isort`

Pkl: Builtins.isort

Python import sorter

Files: **/*.py
Check: isort --check-only {{files}}
Check (diff): isort --check-only --diff {{files}}
Fix: isort {{files}}

`mypy`

Pkl: Builtins.mypy

Static type checker for Python

Files: **/*.py, **/*.pyi
Check: mypy {{files}}

`pylint`

Pkl: Builtins.pylint

Python code analysis

Files: **/*.py
Check: pylint {{files}}

`python-check-ast`

Pkl: Builtins.python_check_ast

Validate Python syntax by parsing the AST

Files: **/*.py
Check: hk util python-check-ast {{files}}

`python-debug-statements`

Pkl: Builtins.python_debug_statements

Detect debug statements in Python code

Files: **/*.py
Check: hk util python-debug-statements {{files}}

`ruff`

Pkl: Builtins.ruff

Fast Python linter

Files: python files
Check: ruff check --force-exclude {{files}}
Check (diff): ruff check --force-exclude --diff --exit-non-zero-on-fix {{ files }} && ruff check --force-exclude {{ files }}
Fix: ruff check --force-exclude --fix {{files}}
Options: check_after_diff = true

`ruff-format`

Pkl: Builtins.ruff_format

Fast Python formatter (part of ruff)

Files: python files
Check (diff): ruff format --quiet --force-exclude --diff {{files}}
Fix: ruff format --quiet --force-exclude {{files}}

`ty`

Pkl: Builtins.ty

Fast Python type checker

Files: **/*.py, **/*.pyi
Check: ty check {{files}}

Ruby

`brakeman`

Pkl: Builtins.brakeman

Security scanner for Rails

Files: ruby files
Check: brakeman -q -w2 {{files}}

`bundle-audit`

Pkl: Builtins.bundle_audit

Dependency security audit

Files: **/Gemfile.lock
Check: bundle-audit check {{files}}
Fix: bundle-audit update

`erb`

Pkl: Builtins.erb

ERB template linter

Files: **/*.erb
Check: erb -P -x -T - {{ files }} | ruby -c

`fasterer`

Pkl: Builtins.fasterer

Performance suggestions

Files: ruby files
Check: fasterer {{files}}

`reek`

Pkl: Builtins.reek

Code smell detector

Files: ruby files
Check: reek {{files}}

`rubocop`

Pkl: Builtins.rubocop

Ruby style guide

Files: **/*.rb, **/*.arb, **/*.axlsx, **/*.builder, **/*.gemfile, **/*.gemspec, **/*.jb, **/*.jbuilder, **/*.mspec, **/*.opal, **/*.pluginspec, **/*.podspec, **/*.rabl, **/*.rake, **/*.rbw, **/*.ru, **/*.ruby, **/*.schema, **/*.spec, **/*.thor, **/.irbrc, **/.pryrc, **/.simplecov, **/buildfile, **/Appraisals, **/Berksfile, **/Brewfile, **/Buildfile, **/Capfile, **/Dangerfile, **/Deliverfile, **/Fastfile, **/*Fastfile, **/Gemfile, **/Guardfile, **/Jarfile, **/Mavenfile, **/Podfile, **/Puppetfile, **/Rakefile, **/rakefile, **/Schemafile, **/Snapfile, **/Steepfile, **/Thorfile, **/Vagrantfile
Check: rubocop --force-exclusion {{files}}
Check (list files): rubocop --force-exclusion --format files {{files}}
Fix: rubocop --force-exclusion --autocorrect {{files}}
Options: exclude = List("node_modules/**/*", "tmp/**/*", "vendor/**/*", ".git/**/*")

`rubocop-server`

Pkl: Builtins.rubocop_server

Ruby style guide (using RuboCop's --server mode)

Files: **/*.rb, **/*.arb, **/*.axlsx, **/*.builder, **/*.gemfile, **/*.gemspec, **/*.jb, **/*.jbuilder, **/*.mspec, **/*.opal, **/*.pluginspec, **/*.podspec, **/*.rabl, **/*.rake, **/*.rbw, **/*.ru, **/*.ruby, **/*.schema, **/*.spec, **/*.thor, **/.irbrc, **/.pryrc, **/.simplecov, **/buildfile, **/Appraisals, **/Berksfile, **/Brewfile, **/Buildfile, **/Capfile, **/Dangerfile, **/Deliverfile, **/Fastfile, **/*Fastfile, **/Gemfile, **/Guardfile, **/Jarfile, **/Mavenfile, **/Podfile, **/Puppetfile, **/Rakefile, **/rakefile, **/Schemafile, **/Snapfile, **/Steepfile, **/Thorfile, **/Vagrantfile
Check: rubocop --server --force-exclusion {{files}}
Check (list files): rubocop --server --force-exclusion --format files {{files}}
Fix: rubocop --server --force-exclusion --autocorrect {{files}}
Options: exclude = List("node_modules/**/*", "tmp/**/*", "vendor/**/*", ".git/**/*")

`sorbet`

Pkl: Builtins.sorbet

Type checker for Ruby

Files: ruby files
Check: srb tc {{files}}

`standard-rb`

Pkl: Builtins.standard_rb

Ruby Standard Style

Files: ruby files
Check: standardrb {{files}}
Fix: standardrb --fix {{files}}

Rust

`cargo-check`

Pkl: Builtins.cargo_check

Fast Rust type checking

Files: **/*.rs
Check: cargo check --quiet
Fix: cargo fix --allow-dirty --allow-staged --quiet

`cargo-clippy`

Pkl: Builtins.cargo_clippy

Rust linter

Files: **/*.rs
Check: cargo clippy --manifest-path {{workspace_indicator}} --quiet
Fix: cargo clippy --manifest-path {{workspace_indicator}} --fix --allow-dirty --allow-staged --quiet
Options: workspace_indicator = "Cargo.toml"

`cargo-deny`

Pkl: Builtins.cargo_deny

Rust dependency linter

Files: **/Cargo.toml, **/Cargo.lock, **/deny.toml, **/.deny.toml, **/deny.exceptions.toml, **/.deny.exceptions.toml
Check: cargo-deny --locked --workspace check
Options: workspace_indicator = "Cargo.toml", dir = "{{workspace}}"

`cargo-fmt`

Pkl: Builtins.cargo_fmt

Rust code formatter

Files: **/*.rs, **/rustfmt.toml, **/.rustfmt.toml
Check: cargo fmt --check --manifest-path {{workspace_indicator}}
Check (list files): cargo fmt --check --manifest-path {{workspace_indicator}} -- --files-with-diff
Fix: cargo fmt --manifest-path {{workspace_indicator}}
Options: workspace_indicator = "Cargo.toml"

`rustfmt`

Pkl: Builtins.rustfmt

Rust code formatter (standalone)

Files: **/*.rs
Check: rustfmt --check --edition 2024 {{files}}
Check (list files): rustfmt --check --edition 2024 --files-with-diff {{files}}
Fix: rustfmt --edition 2024 {{files}}

Secrets

`betterleaks`

Pkl: Builtins.betterleaks

A Better Secrets Scanner built for configurability and speed

Files: text files
Check: betterleaks dir --redact --verbose --no-banner {{files}}

`gitleaks`

Pkl: Builtins.gitleaks

Secret scanner for repository working trees

Check: gitleaks dir --redact --verbose --no-banner .

`kingfisher`

Pkl: Builtins.kingfisher

Secret scanner with live validation and 1,000+ rules

Files: text files
Check: kingfisher scan {{files}} --no-update-check --no-validate --quiet

Shell

`shellcheck`

Pkl: Builtins.shellcheck

Shell script analyzer

Files: **/*.sh, **/*.bash; or sh, bash files
Check: shellcheck {{files}}
Check (diff): shellcheck --format=diff {{files}}
Options: batch = true, check_after_diff = true

`shellharden`

Pkl: Builtins.shellharden

The corrective bash syntax highlighter

Files: bash, sh files
Check: shellharden --check {{files}}
Check (diff): hk util format-diff --no-stdin {{files}} -- shellharden --transform '{}'
Fix: shellharden --replace {{files}}
Options: batch = true

`shfmt`

Pkl: Builtins.shfmt

Shell formatter

Files: **/*.sh, **/*.bash, **/*.mksh, **/*.bats, **/*.zsh; or sh, bash files
Check (diff): shfmt -d --apply-ignore {{ files }}

Check (list files):

files=$(shfmt -l --apply-ignore {{ files }})
if [ -n "$files" ]; then
echo "$files"
exit 1
fi

Fix: shfmt -w --apply-ignore {{ files }}
Options: batch = true

Special Purpose

`byte-order-marker`

Pkl: Builtins.byte_order_marker

Detect UTF-8 BOM

Files: text files
Check (diff): hk util check-byte-order-marker --diff {{files}}
Fix: hk util fix-byte-order-marker {{files}}

`check-added-large-files`

Pkl: Builtins.check_added_large_files

Prevent committing large files

Files: **/*
Check: hk util check-added-large-files {{files}}
Options: allow_binary = true

`check-case-conflict`

Pkl: Builtins.check_case_conflict

Detect case-insensitive filename conflicts

Files: **/*
Check: hk util check-case-conflict {{files}}
Options: allow_binary = true, allow_symlinks = true

`check-conventional-commit`

Pkl: Builtins.check_conventional_commit

Verify commit message matches conventional commits formatting

Check: hk util check-conventional-commit {{commit_msg_file}}

`check-executables-have-shebangs`

Pkl: Builtins.check_executables_have_shebangs

Verify executable files have shebang lines

Files: text files
Check: hk util check-executables-have-shebangs {{files}}

`check-merge-conflict`

Pkl: Builtins.check_merge_conflict

Detect merge conflict markers

Files: text files
Check: hk util check-merge-conflict --assume-in-merge {{files}}

`check-shebang-scripts-are-executable`

Pkl: Builtins.check_shebang_scripts_are_executable

Verify files with shebang lines are executable

Files: text files
Check: hk util check-shebang-scripts-are-executable {{files}}

`check-symlinks`

Pkl: Builtins.check_symlinks

Detect broken symlinks

Files: **/*
Check: hk util check-symlinks {{files}}
Options: allow_symlinks = true

`cocogitto-commit-msg`

Pkl: Builtins.cocogitto_commit_msg

Conventional commits linter

Check: cog --quiet verify --file {{commit_msg_file}}

`destroyed-symlinks`

Pkl: Builtins.destroyed_symlinks

Detect symlinks replaced by regular files holding their target path

Check: hk util destroyed-symlinks

`detect-private-key`

Pkl: Builtins.detect_private_key

Detect accidentally committed private keys

Files: text files
Check: hk util detect-private-key {{files}}

`fix-smart-quotes`

Pkl: Builtins.fix_smart_quotes

Replace smart quotes with regular quotes

Files: text files
Check (diff): hk util fix-smart-quotes --diff {{files}}
Fix: hk util fix-smart-quotes {{files}}

`forbid-submodules`

Pkl: Builtins.forbid_submodules

Forbid git submodules in the repository

Check: hk util forbid-submodules

`harper`

Pkl: Builtins.harper

Grammar checker for prose and documentation

Files: text files
Check: harper-cli lint {{files}}

`harper-commit-message`

Pkl: Builtins.harper_commit_message

Grammar checker for commit message

Check: harper-cli lint {{commit_msg_file}}

`hk-test`

Pkl: Builtins.hk_test

Run step-defined hk's tests

Files: hk.pkl, .config/hk.pkl
Check: hk test --quiet

`just-format`

Pkl: Builtins.just_format

Justfile formatter

Files: **/justfile, **/*.just

Fix:

xargs -d'
' -I {} -- just --fmt --unstable --justfile {}

`ls-lint`

Pkl: Builtins.ls_lint

Directory and filename naming linter

Files: **/*
Check: ls-lint
Options: allow_binary = true, allow_symlinks = true

`lychee`

Pkl: Builtins.lychee

Fast, async, stream-based link checker

Files: text files
Check: lychee --no-progress {{files}}

`lychee-extended`

Pkl: Builtins.lychee_extended

Flint's repository-aware link check (requires flint and lychee). See https://github.com/grafana/flint/blob/main/docs/linters/lychee.md

Files: text files
Check: flint checker lychee --files-from -

`mixed-line-ending`

Pkl: Builtins.mixed_line_ending

Detect and fix mixed line endings

Files: text files
Check (diff): hk util mixed-line-ending --diff {{files}}
Fix: hk util mixed-line-ending --fix {{files}}

`newlines`

Pkl: Builtins.newlines

Ensure files end with newline

Files: text files
Check (diff): hk util end-of-file-fixer --diff {{files}}
Fix: hk util end-of-file-fixer --fix {{files}}

`no-commit-to-branch`

Pkl: Builtins.no_commit_to_branch

Prevent direct commits to protected branches

Check: hk util no-commit-to-branch

`renovate-deps`

Pkl: Builtins.renovate_deps

Flint's repository-aware dependency check (requires flint and renovate). See https://github.com/grafana/flint/blob/main/docs/linters/renovate-deps.md

Files: **/*
Check: flint checker renovate-deps --files-from -
Fix: flint checker renovate-deps --fix --files-from -
Options: stage = List(".github/renovate-tracked-deps.json")

`textlint`

Pkl: Builtins.textlint

Pluggable natural language linter

Files: **/*.md, **/*.markdown, **/*.txt
Check: textlint {{files}}
Fix: textlint --fix {{files}}
Options: batch = true

`trailing-whitespace`

Pkl: Builtins.trailing_whitespace

Detect and remove trailing whitespace

Files: text files
Check (diff): hk util trailing-whitespace --diff {{files}}
Fix: hk util trailing-whitespace --fix {{files}}

`typos`

Pkl: Builtins.typos

Source code spell checker

Files: text files

Check (diff):

status=0
output=$(typos --force-exclude --diff {{files}}) || status=$?
[ -z "$output" ] && exit "$status"
printf "%s" "$output"
exit 1

Fix: typos --force-exclude --write-changes {{ files }}

`vale`

Pkl: Builtins.vale

Prose linter for markup and code comments

Files: text files
Check: vale sync && vale {{ files }}

Typst

`tinymist`

Pkl: Builtins.tinymist

Typst linter (requires tinymist 0.14.20 or newer)

Files: **/*.typ

Check:

code=0
for f in {{ files }}; do
  tinymist lint "$f" || code=$?
done
exit "$code"

Options: batch = true, shell = "sh -c"

`typstyle`

Pkl: Builtins.typstyle

Typst formatter

Files: **/*.typ
Check (diff): typstyle --diff {{files}}
Fix: typstyle --inplace {{files}}

YAML

`ryl`

Pkl: Builtins.ryl

Re-implementation of yamllint in Rust

Files: yaml files
Check: ryl check {{files}}
Check (diff): ryl check --diff {{files}}
Check (list files): ryl check --list-files {{files}}
Fix: ryl check --fix {{files}}
Options: check_after_diff = true

Bring a tool of yer own aboard

If there's no builtin for yer tool, define a step with glob, check, and an optional fix command. Only enable batching if the tool can process independent subsets of the files correctly.

See custom steps for a complete example. And, as the song goes, all you hands who would sign aboard: see contributing to add a reusable definition to the standing crew.

agent

config

migrate

run

util

The standing crew: built-in linters ​

Muster a builtin ​

Refit a builtin ​

Utilities hk carries aboard ​

Tools on hand ​

The crew roster ​

.NET ​

dotnet-format ​

AsciiDoc ​

asciidoctor ​

Build Systems ​

buildifier-format ​

buildifier-lint ​

CSS ​

stylelint ​

Configuration ​

sort-package-json ​

Data Formats ​

buf-format ​

buf-lint ​

jq ​

sql-fluff ​

taplo ​

taplo-format ​

tombi ​

tombi-format ​

xmllint ​

yamlfmt ​

yamllint ​

yq ​

EditorConfig ​

editorconfig-checker ​

Elixir ​

mix-compile ​

mix-fmt ​

mix-test ​

Go ​

err-check ​

go-fix ​

go-fmt ​

go-fumpt ​

go-imports ​

go-lines ​

go-sec ​

go-vet ​

go-vuln-check ​

golangci-lint ​

golangci-lint-fmt ​

gomod-tidy ​

revive ​

staticcheck ​

Infrastructure ​

actionlint ​

dclint ​

droast ​

ghalint-action ​

ghalint-workflow ​

hadolint ​

hclfmt ​

jactionlint ​

kube-linter ​

kubeconform ​

mise ​

pinact ​

pinact-update ​

terraform ​

terraform-docs ​

terraform-validate ​

terragrunt-hcl-fmt ​

terragrunt-hcl-validate ​

tf-lint ​

tofu ​

zizmor ​

Java ​

google-java-format ​

The standing crew: built-in linters

Muster a builtin

Refit a builtin

Utilities hk carries aboard

Tools on hand

The crew roster

.NET

`dotnet-format`

AsciiDoc

`asciidoctor`

Build Systems

`buildifier-format`

`buildifier-lint`

CSS

`stylelint`

Configuration

`sort-package-json`

Data Formats

`buf-format`

`buf-lint`

`jq`

`sql-fluff`

`taplo`

`taplo-format`

`tombi`

`tombi-format`

`xmllint`

`yamlfmt`

`yamllint`

`yq`

EditorConfig

`editorconfig-checker`

Elixir

`mix-compile`

`mix-fmt`

`mix-test`

Go

`err-check`

`go-fix`

`go-fmt`

`go-fumpt`

`go-imports`

`go-lines`

`go-sec`

`go-vet`

`go-vuln-check`

`golangci-lint`

`golangci-lint-fmt`

`gomod-tidy`

`revive`

`staticcheck`

Infrastructure

`actionlint`

`dclint`

`droast`

`ghalint-action`

`ghalint-workflow`

`hadolint`

`hclfmt`

`jactionlint`

`kube-linter`

`kubeconform`

`mise`

`pinact`

`pinact-update`

`terraform`

`terraform-docs`

`terraform-validate`

`terragrunt-hcl-fmt`

`terragrunt-hcl-validate`

`tf-lint`

`tofu`

`zizmor`

Java

`google-java-format`

JavaScript/TypeScript

`biome`

`deno`

`deno-check`

`eslint`