envproof 0.1.0

Validate environment variables at startup with typed, clear error messages. Zero dependencies.

envguard

Validate environment variables at startup with typed, clear error messages. Zero dependencies.

from envguard import EnvGuard

class Env(EnvGuard):
    DATABASE_URL: str
    PORT: int = 8080
    DEBUG: bool = False
    ALLOWED_HOSTS: list = []

env = Env()
print(env.PORT)  # 8080 (int, not string)

If DATABASE_URL is missing, you get this instead of a cryptic KeyError somewhere deep in your app:

EnvGuardError:
Missing required environment variables:
  - DATABASE_URL (str): not set

Install

pip install envguard

Usage

Subclass style (recommended)

from envguard import EnvGuard

class Env(EnvGuard):
    # Required — raises if not set
    DATABASE_URL: str
    API_KEY: str

    # Optional — uses default if not set
    PORT: int = 8080
    DEBUG: bool = False
    LOG_LEVEL: str = "INFO"
    ALLOWED_HOSTS: list = []

env = Env()

One-liner style

from envguard import guard

env = guard(DATABASE_URL=str, PORT=int, DEBUG=bool)
print(env.DATABASE_URL)

Supported types

Type	Example env value	Python value
str	"hello"	"hello"
int	"8080"	8080
float	"3.14"	3.14
bool	"true", "1", "yes"	True
bool	"false", "0", "no"	False
list	"a,b,c"	["a", "b", "c"]

Error messages

All errors are collected and reported together — you won't fix one missing var only to discover another:

EnvGuardError:
Missing required environment variables:
  - DATABASE_URL (str): not set
  - API_KEY (str): not set

Invalid environment variable values:
  - PORT: expected int, got 'abc'
  - DEBUG: expected bool, got 'maybe'

Why not pydantic-settings?

pydantic-settings is great but pulls in Pydantic as a dependency (~2MB). envguard is a single file with zero dependencies — useful when you want validation without adding weight to your project.

License

MIT