Registry / serialization / lazy-imports

lazy-imports

JSON →
library1.2.0pypypi✓ verified 24d ago

lazy-imports is a Python library (current version 1.2.0) designed to facilitate lazy loading of modules and symbols, primarily to reduce application startup times. It provides decorators and functions to defer the actual import process until the imported object is first accessed. The library is actively maintained with updates released as needed.

pip install lazy-imports
INSTALL
IMPORT
SIG · LAZY-IMPORTS
L
lazy-imports
serializationpythonv1.2.0
Install
1.5s avg
Import
55ms
Disk
16MB
Pass rate
10/ 10
Env Coverage10 / 10
glibc
3.93.13
musl
3.93.13
Install & Compatibility
Where this runs
tested against v1.2.0 · pip install
no network on importno background threads
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
py 3.103.95 runs
installs and imports cleanly · install 0.0s · import 0.058s · 17.9MB
glibc
py 3.103.95 runs
installs and imports cleanly · install 1.5s · import 0.052s · 18MB
16MB installed
● package 16MB
Code
Verified usage

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

LazyImporter
from lazy_imports import LazyImporter
from lazy_imports import lazy_import
lazy_module
from lazy_imports import lazy_module
load
from lazy_imports import load

This example demonstrates how to lazily import a specific function (`loads` from `json`) using `lazy_import`. The `json` module is only loaded into memory when `loads` is first invoked, illustrating the startup performance benefit.

from lazy_imports import lazy_import # Defer import of 'json' module's 'loads' function # The 'json' module will only be loaded when 'loads' is first called. loads = lazy_import("json", "loads") print("json.loads not yet imported...") data = loads('{"key": "value"}') # The actual 'json' import happens here print(f"Data loaded: {data}") # Example with a module (using the decorator) # from lazy_imports import lazy_module # @lazy_module("os") # def get_path_sep(): # return os.path.sep # print(f"Path separator: {get_path_sep()}")
Debug
Known issues
gotchaLazy imports can interfere with IDE auto-completion, refactoring tools, and static analysis (e.g., MyPy), potentially leading to 'unresolved reference' warnings or missing type hints.
fix
Use type-checking comments (`if TYPE_CHECKING: import ...`) or stub files (`.pyi`) to provide type information for static analysis without triggering eager imports, or accept reduced IDE support.
affects: All versions
gotchaDebugging code with lazy imports can be challenging as the actual module import happens at the point of first access, not at the `lazy_import` definition, which can lead to unexpected exceptions or load delays at runtime.
fix
Be aware of the deferred loading mechanism. Temporarily replace lazy imports with direct imports for intense debugging sessions, or set breakpoints strategically where the lazy object is first used.
affects: All versions
gotchaWhile lazy imports can defer the *resolution* of circular dependencies, they do not fundamentally solve circular import *design* issues and can sometimes mask them, leading to runtime errors if not handled carefully.
fix
Prioritize refactoring to eliminate circular dependencies. Use lazy imports only as a last resort or for specific performance optimizations where a cycle is unavoidable and well-understood.
affects: All versions
gotchaLazy imports introduce a small, one-time runtime overhead when the imported object is first accessed, as the module must then be loaded. For very frequently accessed or extremely small modules, this overhead might outweigh startup time benefits.
fix
Profile your application to ensure that the performance benefits of lazy loading outweigh the first-access overhead in critical paths. Use lazy imports strategically for larger, less frequently accessed modules or for startup-critical paths.
affects: All versions
Upgrade
Version history
1.2.0latest on PyPI · released Dec 28, 2025
Audit
Dependencies

No dependency data recorded yet.

Agent activity
9 hits · last 30 days
node
8
Resources
lazy-imports — pip install lazy-imports · libregistry