Varlock

This skill helps securely manage env vars and secrets in your project using varlock.

Docs: https://varlock.dev Repo: https://github.com/dmno-dev/varlock

Varlock uses .env.schema (instead of .env.example) to provide a single source of truth for your project's env vars. Schema info is expressed using @decorator style comments. Sensitive values can be set in git-ignored .env.local files, passed in via the environment, or use functions to load from secure backends like 1Password, Vault, AWS, etc.

Basic .env.schema example:

# @defaultSensitive=false @defaultRequired=infer
# @currentEnv=$APP_ENV
# @generateTsTypes(path=env.d.ts)
# ---

# @type=enum(dev, staging, prod)
APP_ENV=dev

# @type=url
API_URL=https://api.example.com

# Description of this var
# @sensitive @required @type=string(startsWith=sk-)
# @docs(https://xyzapi.com/docs/auth)
XYZ_API_KEY=

Your .env.schema is committed to version control and safe for agents to read and update. The varlock CLI helps load and validate env vars while masking anything sensitive, and can securely inject env vars into commands.

NOTE: If varlock is installed locally via package.json (not as a standalone binary), invoke it via your package manager — e.g., pnpm exec varlock load, bunx varlock load, npm exec varlock load. Check the project's package manager before running CLI commands.

CRITICAL: Security rules

These rules are non-negotiable:

Do not expose secrets

# NEVER do these - exposes secrets to agent context
cat .env
cat .env.local
echo $SECRET_KEY
printenv | grep API

# SAFE alternatives
varlock load --agent    # JSON output, sensitive values redacted
varlock load            # human-readable, sensitive values masked
cat .env.schema         # schema only, no secret values

If the user needs to see a sensitive value, tell them to run varlock reveal VAR_NAME.

File access rules

• Safe to read and edit: .env.schema and any other git-committed .env files (usually env-specific files like .env.development)
• Do not read or edit: .env, .env.local, .env.[env].local, or other gitignored value/override files — these may contain unencrypted secrets
• Do not log or quote raw secret values in code, comments, or chat

Sensitivity rules

• Items marked @sensitive must not have that decorator removed without confirming with the user
• Ask the user to edit secret values in their local/gitignored env files or their secret provider (1Password, AWS, etc.) — never fill in secrets yourself

When the user asks to "show me the .env file"

Do not read .env or .env.local directly. Instead run varlock load to show masked values, or read .env.schema to show the schema. Explain that reading env files directly could expose secrets.

When the user asks to "update/set a secret"

Do not write secret values yourself. Tell the user to either:

1. Update it in their secret provider (1Password, AWS, etc.) and then help them wire it up
2. Edit the value in their .env.local file manually

• ideally encrypt it by using varlock(prompt) as the value, then run varlock load to be prompted

Then run varlock load --agent to validate.

File roles

Ensure .env.schema and tracked env-specific files are not gitignored (!.env.schema, !.env.production, etc. in .gitignore if needed).

Environment-specific files and precedence

When @currentEnv is set in .env.schema (e.g., @currentEnv=$APP_ENV), varlock automatically loads matching environment-specific files. Files are applied in increasing precedence order:

.env.schema < .env < .env.local < .env.[currentEnv] < .env.[currentEnv].local < process.env

For example, if APP_ENV=staging, then .env.staging and .env.staging.local will be loaded automatically if they exist. A value in .env.local overrides one in .env.schema, and process.env always wins.

A bare KEY= sets no value at all, so it does not override a value from a lower-precedence file. Use KEY="" to override with an empty string.

Schema syntax

Root decorators (file header)

Root decorators go in comment blocks at the top of the file, before the first item. A # --- divider usually separates the header from items.

• @defaultSensitive defaults to true — all items are sensitive unless explicitly marked @public or @sensitive=false. Set @defaultSensitive=false to flip the default.
• @defaultRequired=infer: items with a value in the schema are required, items without are optional. Without this decorator, items default to required
• varlock init writes @defaultRequired=infer and @defaultSensitive=false into the schema it generates, so most existing projects run with those rather than the absent-decorator behavior. Read the file header before assuming either
• Item defaults (@defaultRequired, @defaultSensitive) only apply to items defined in the same file. An item defined only in a .env.local or an imported file falls back to the built-in defaults (required, sensitive), no matter what the root schema sets
• @defaultSensitive=inferFromPrefix(PUBLIC_): items with keys starting with PUBLIC_ are not sensitive, all others are
• @import() accepts enabled=expr for conditional imports and allowMissing=true for optional imports

Item decorators

Decorators in comment lines directly preceding a config item are attached to that item. A blank line breaks the association.

Decorator values can use resolver functions: @required=forEnv(prod), @sensitive=not(forEnv(dev)).

Common data types (@type=)

string(startsWith=X), string(matches=/regex/), number, boolean, url, email, port, enum(a, b, c), ipAddress, semver

Plain string is the default — do not add @type=string, just omit @type entirely. Only use @type when you need a specific type or string constraints. See https://varlock.dev/reference/data-types/

Resolver functions (values)

Instead of static values, items can use resolver functions:

# Reference another item ($VAR and ${VAR} are shorthand for ref(VAR))
FULL_URL=${API_URL}/v2/users

# Execute a CLI command
SECRET=exec(`op read "op://vault/item/field"`)

# Conditional logic
API_URL=if(eq($APP_ENV, prod), https://api.example.com, http://localhost:3000)

# First non-empty value
FALLBACK_VAR=fallback($PRIMARY, $SECONDARY, "default")

# Map one value to another
APP_ENV=remap($CI_BRANCH, "main", production, /.*/, preview, undefined, development)

# Check environment (based on @currentEnv)
# @required=forEnv(prod, staging)
PROD_ONLY_KEY=

Key functions: ref(), concat(), exec(), fallback(), if(), eq(), not(), isEmpty(), ifs(), remap(), forEnv()

See https://varlock.dev/reference/functions/

Setting sensitive values

There are two main approaches — they can be used together.

Approach 1: Plugins (version-controlled secret references)

Varlock plugins let you declaratively reference secrets from external providers directly in your .env.schema. The references are safe to commit — actual values are fetched at load time.

# @plugin(@varlock/1password-plugin)
# @initOp(token=$OP_TOKEN, allowAppAuth=forEnv(dev))
# ---
# @sensitive @type=opServiceAccountToken
OP_TOKEN=
# @sensitive
MY_SECRET=op(op://my-vault/item-name/field-name)

Each plugin provides its own resolver functions (e.g., op() for 1Password, awsSecret() for AWS). See Plugins below for the full list and https://varlock.dev/guides/plugins/ for setup details.

Approach 2: Local encryption with varlock() (git-ignored files)

For secrets stored locally in git-ignored files like .env.local, use the varlock() function for device-local encryption so nothing is stored in plaintext:

# Encrypted value — decrypted automatically at load time
API_KEY=varlock("local:<encrypted-payload>")

# Prompt mode — on next `varlock load`, user is prompted to enter the value
# which is encrypted and written back to this file automatically
NEW_SECRET=varlock(prompt)

How to encrypt values:

• Interactive prompt: Set the value to varlock(prompt) and run varlock load — the user will be prompted securely, and the encrypted value replaces the placeholder automatically
• Encrypt in bulk: varlock encrypt --file .env.local encrypts all sensitive plaintext values in-place
• Encrypt a single value: varlock encrypt prompts for a value and prints the encrypted result to copy/paste
• Pipe via stdin: To encrypt a value without exposing it in your context (e.g., a generated key or a value read from another tool), pipe it into varlock encrypt:

  some-cli-that-outputs-secret | varlock encrypt
  # prints: SOME_SENSITIVE_KEY=varlock("local:<encrypted>")
  

  This keeps the plaintext secret out of shell history and agent context.

Encryption is hardware-backed on macOS (Secure Enclave + Touch ID), Windows (DPAPI + Windows Hello), and Linux (TPM2), with a file-based fallback on all platforms. On macOS, keychain() is also available as a built-in alternative that stores values in the system keychain.

See https://varlock.dev/guides/local-encryption/

Organization

Ask the user how their repo is structured before designing the env layout.

Single project: one .env.schema at the repo root is usually enough.

Monorepo / multi-app: use @import() to share common config:

# Import shared config from root (directory form: also loads root .env / .env.local)
# @import(../../)
# Import from a sibling service (specific keys only)
# @import(../api/.env.schema, pick=[SHARED_API_URL, SHARED_DB_HOST])
# ---
APP_PUBLIC_URL=http://localhost:3000

• Root schema — shared service URLs, org-wide defaults, common keys
• Per-app schemas — app-specific items, importing what they need from root/siblings
• Keep imports explicit; avoid circular imports

Discuss with the user: which values belong at the root vs per-package, which environments they use.

See https://varlock.dev/guides/import/

Plugins

Plugins add resolver functions, data types, and decorators for external secret providers. Install with @plugin() in your .env.schema:

# @plugin(@varlock/1password-plugin)

In JS projects, also install the npm package. With the standalone binary, pin a version: @plugin(@varlock/1password-plugin@1.2.3).

Available plugins: 1Password, AWS Secrets Manager, Azure Key Vault, Bitwarden, Dashlane, Doppler, Google Secret Manager, HashiCorp Vault, Infisical, Akeyless, KeePass, Keeper, Passbolt, Proton Pass, Pass, macOS Keychain (built-in).

See https://varlock.dev/plugins/overview/ for setup details for each plugin.

Integrations (frameworks / runtimes)

Pick the official integration for the project's framework — do not guess. Check https://varlock.dev/integrations/overview/ for the specific guide (Next.js, Vite, Astro, SvelteKit, Bun, Cloudflare, Expo, etc.).

Typical steps:

1. Confirm varlock is installed (varlock init --agent or existing dependency)
2. Follow the integration guide for build/dev wiring, generated types, and any required config
3. Prefer the integration's recommended entry point (varlock/auto-load, Vite plugin, etc.) over ad-hoc process.env usage

When a framework integration is active, it handles loading and injecting env vars automatically — varlock run is not needed for the framework's own dev/build commands. Only use varlock run -- <cmd> for other scripts or tools that the integration doesn't cover (e.g., one-off migrations, CLI tools, non-JS commands).

Migrating from dotenv: replace dotenv/config or dotenvx run with the varlock equivalent — see https://varlock.dev/guides/migrate-from-dotenv/

Non-JS apps/services: use varlock run or pipe varlock load --format shell — see https://varlock.dev/integrations/other-languages/

Setup

Installing varlock:

• JS projects: Install as a dev dependency — npm install -D varlock (or bun add -D varlock, pnpm add -D varlock)
• Standalone binary (non-JS or global use): See https://varlock.dev/getting-started/installation/

Getting started:

1. Run varlock init --agent to auto-generate an initial .env.schema from existing .env / .env.example files
2. Review the generated schema with the user — init heuristics are a draft, not final
3. Optionally install this skill:
   • skills (recommended): npx skills add dmno-dev/varlock — update with npx skills update varlock
   • GitHub CLI (v2.90+): gh skill install dmno-dev/varlock varlock — update with gh skill update varlock

Schema checklist

After init or when editing .env.schema:

1. Review auto-generated items — heuristics are not final
2. Add description comments where names are not self-explanatory
3. Set @type only when not a plain string (omit @type=string)
4. Mark @required / @optional as needed (or adjust root @defaultRequired)
5. Confirm @sensitive on secrets, keys, tokens, and credentials with the user
6. Move useful values to @example; delete dummy placeholders
7. Add @docs() links where helpful
8. Remove redundant values from other .env files after defaults move into the schema

Validation loop

After schema changes:

varlock load --agent

Fix schema and tracked env files based on validation errors. Do not patch gitignored .local value files to silence schema errors — ask the user to update secrets locally.

CLI quick reference

Run varlock --help or varlock <command> --help for full flags and options.

Updating an existing project

Keep .env.schema as the source of truth. Edit schema and tracked .env.[env] files only — not gitignored .local files.

1. Schema changes — add/remove/rename items in .env.schema, update code to match, then varlock load --agent
2. Secrets — leave sensitive values empty in schema; ask the user to set them locally or in their secret provider
3. Plugins — add @plugin() in the header and prefer plugin resolvers over raw exec() when available
4. Codegen — @generateTsTypes (and the other @generate*Env decorators) run on load by default; use auto=false and varlock codegen if you need explicit control
5. Before commit — varlock load --agent, then varlock scan --staged; run varlock audit if you renamed keys or suspect drift

See Schema, Secrets, and Monorepos for deeper patterns.

Advanced

• Multiple environments: https://varlock.dev/guides/environments/
• Split large schemas with @import: https://varlock.dev/guides/import/
• Device-local encryption: https://varlock.dev/guides/local-encryption/
• package.json config (varlock.loadPath): https://varlock.dev/reference/cli-commands/
• Built-in variables ($VARLOCK_ENV for auto-detecting environment): https://varlock.dev/reference/builtin-variables/

Docs

For details beyond this skill, use the Varlock Docs MCP tool if installed in your AI tool, or refer to https://varlock.dev/guides/schema as a starting point.