evp-ts

library1.1.1jsnpmunverified

Lightweight environment variable parser for TypeScript, inspired by Zod and Haskell's EVP. Current stable version 1.1.1 is actively maintained with regular releases. Supports nested object parsing, type inference, secret masking, default values, optional fields, and dotenv-style help generation. Key differentiators: low dependency footprint, comprehensive error reporting that continues parsing all variables, and explicit logging with secret hashing. Alternative to dotenv with stronger typing and validation, but less mature ecosystem.

http-networking

npm install evp-ts

github ↗package ↗

INSTALL

IMPORT

SIG · EVP-TS

evp-ts

http-networkingjavascriptv1.1.1

Install

—

Import

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Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

EVP

✓ import { EVP } from 'evp-ts'

✗ const EVP = require('evp-ts')

ESM-only. No CommonJS support.

EVP.infer

✓ type Config = EVP.infer<typeof parser>

✗ type Config = Infer<typeof parser>

EVP.infer is a type utility on the imported EVP namespace, not a separate export.

EVP.string

✓ import { EVP } from 'evp-ts'; const s = EVP.string()

✗ import { string } from 'evp-ts'

All parsers are methods on the EVP object, not named exports.

Shows parsing environment variables with types, defaults, secret masking, and custom env names.

import { EVP } from 'evp-ts'; const parser = EVP.object({ API_ENDPOINT: EVP.string(), API_TOKEN: EVP.string().secret(), HTTP_PORT: EVP.number(), DEBUG_MODE: EVP.boolean().default(false), DB_HOST: EVP.string().default('localhost').env('MYSQL_HOST'), DB_PORT: EVP.number().default(3306).env('MYSQL_PORT'), }); type Config = EVP.infer<typeof parser>; const config: Config = parser.parse(); console.log(config.API_ENDPOINT); // => string console.log(config.HTTP_PORT); // => number console.log(config.DEBUG_MODE); // => false (default)

Debug

Known issues

breakingEVP.infer changed from returning a tuple to a single type in v1.0.0

fix

Update usage to align with v1.x: EVP.infer<typeof parser> now returns the inferred config object type directly.

affects: <1.0.0

deprecatedEVP.boolean() accepts 'yes'/'no' as truthy/falsy; this is unconfigurable and may not match all locales

fix

Use EVP.string() with custom validation if you need other truthy/falsy strings.

affects: >=1.0.0

gotchaparse() does not throw on missing optional fields; it returns undefined for those keys

fix

Check for undefined or use .default() to ensure a value.

affects: >=1.0.0

gotchaSecret values are hashed with SHA-256 in logs; only the hash is shown, but the actual value is still accessible in code

fix

Be careful not to log the config object directly in production.

affects: >=1.0.0

Errors

Common errors & fixes

TypeError: EVP.infer is not a function

EVP.infer is a type-level utility, not a runtime function. It cannot be used in JavaScript files or at runtime.

fix

Only use EVP.infer in TypeScript type annotations: type T = EVP.infer<typeof parser>

Cannot find module 'evp-ts' or its corresponding type declarations.

Missing @types/evp-ts or not installed with TypeScript (but package ships types). Possibly bundler misconfiguration.

fix

Ensure tsconfig.json has 'strict' or 'esModuleInterop' enabled. Try reinstalling: npm install evp-ts

ReferenceError: EVP is not defined

Using CommonJS require without destructuring correctly, or running in a non-ESM environment without transpilation.

fix

Use the ESM import syntax: import { EVP } from 'evp-ts'

Error: Environment variable API_TOKEN is missing and no default provided

Required environment variable not set and no default with .default() or .optional().

fix

Set the variable or add .default(value) or .optional() to the parser definition.

Upgrade

Version history

1.1.1latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

22 hits · last 30 days

node

Amazon

OpenAI (training)

Resources

githubhttps://github.com/fumieval/evp-ts ↗

packagehttps://www.npmjs.com/package/evp-ts ↗