jinja2-fragments

What it is and what it does

Jinja2 Fragments extends Jinja2 to render individual named blocks from templates as standalone HTML fragments, rather than forcing you to split templates into separate files. This solves the locality-of-behavior problem: you keep a single template file containing both the full page and its reusable blocks, then render just the block you need at runtime.

The package provides framework-specific integrations for Flask, Quart, Starlette, FastAPI, Sanic, and Litestar, each exposing a `render_block()` function or wrapper class that fits naturally into that framework's template API. It also supports rendering multiple blocks at once and concatenating them, which is useful for HTMX out-of-band updates. The core dependency is jinja2 alone.

Use it for:

• Serve partial HTML updates via HTMX without maintaining separate template files for fragments.
• Render individual page sections (header, content, footer) on demand in a single-file template structure.
• Enable out-of-band updates in HTMX by rendering and returning multiple blocks in one response.
• Build dynamic web UIs where different endpoints return different template blocks with shared context.
• Simplify template organization by keeping related block definitions in one file instead of scattered includes.

Worth the install?

AI-flagged interpretation of the facts on this page — verify before relying

Renders individual Jinja2 template blocks as HTML fragments instead of full pages, enabling partial template rendering for HTMX and other dynamic HTML patterns.

Yes. This is a focused, low-friction tool that solves a real problem for HTMX-based and fragment-driven web architectures. It has no security issues, minimal dependencies, active maintenance, and framework integrations that fit naturally into Flask, FastAPI, and other common stacks. Install it if you're already using Jinja2 and need to render template fragments.

Install

jinja2-fragments on PyPI

pip install jinja2-fragments

uv add jinja2-fragments

poetry add jinja2-fragments

Installing jinja2-fragments

Before you install

Low friction: pure Python package with only jinja2 as a runtime dependency, distributed as a wheel. Actively maintained with recent releases and no known vulnerabilities.

License in practice

MIT license permits unrestricted use, modification, and distribution with minimal obligations—suitable for both open-source and commercial projects.

Quickstart

from jinja2 import Environment, FileSystemLoader, select_autoescape
from jinja2_fragments import render_block

environment = Environment(
    loader=FileSystemLoader("my_templates"),
    autoescape=select_autoescape(("html", "jinja2")),
)
rendered_html = render_block(
    environment, "page.html.jinja2", "content", magic_number=42
)

Requires Python 3.9 or later.

Verify before relying

• Performance characteristics when rendering many blocks from large templates.
• Compatibility with custom Jinja2 extensions or filters beyond standard Jinja2.
• Whether nested block rendering or conditional block selection is supported.

Package facts

Evidence: jinja2_fragments-1.12.0-py3-none-any.whl

Tags

More Dynamic Content packages