Kida Template Engine

Template engine with unified block endings, pattern matching, pipelines, and automatic caching

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Bengal's default template engine. Kida renders templates faster than Jinja2, supports free-threaded Python, and caches site-scoped blocks automatically.

Performance: Single-threaded, Kida is 3.4x faster on minimal templates. Under concurrent workloads (8 workers), Kida is 1.81x faster than Jinja2 due to its thread-safe, GIL-independent design.

{% let posts = site.pages |> where('type', 'blog') |> take(5) %}

{% for post in posts %}
  <article>
    <h2>{{ post.title }}</h2>
    <time>{{ post.date | dateformat('%B %d, %Y') }}</time>
  </article>
{% end %}

Jinja2 compatibility: Most Jinja2 templates work without changes. Kida parses both Jinja2 syntax ({% endif %},{% endfor %}, etc.) and Kida-native syntax ({% end %},|>,?.,??). However, Kida does not support all Jinja2 features—notably,{% macro %}is not supported (use{% def %}instead). If you need full Jinja2 compatibility, you can use the Jinja2 engine by settingtemplate_engine: jinja2in your config.

Key Features

Feature Benefit Example
Unified endings {% end %}for all blocks {% if %}...{% end %}instead of{% endif %}
Pattern matching {% match %}...{% case %}replacesif/elifchains Cleaner branching logic
Pipeline operator |>for left-to-right filter chains items |> filter() |> sort() |> take(5)
Optional chaining ?.for safe navigation user?.profile?.namereturnsNoneif any part is missing
Null coalescing ??for concise fallbacks page.subtitle ?? page.titleuses subtitle if available
Scope-aware functions {% def %}functions access outer variables No need to passsiteorconfigas parameters
Automatic caching Site-wide blocks render once per build Navigation, footer cached automatically

Topics

Syntax
Kida template syntax reference
Caching
Automatic and manual template caching
Migration
Migrating to Kida from Jinja2

Standalone Pages

Create a Custom Template
Build a custom template from scratch using Kida syntax
Kida Architecture
Compilation pipeline, AST structure, and rendering implementation
Add a Custom Filter
Extend Kida with your own template filters
Kida Performance
Automatic caching, free-threading, and optimization strategies

Quick Syntax Reference

Feature Kida Jinja2 Notes
Block endings {% end %} {% endif %},{% endfor %}, etc. Unified syntax for all blocks
Template variables {% let x = ... %} {% set x = ... %} Template-scoped assignment
Pattern matching {% match %}...{% case %} {% if %}...{% elif %} Replaces long if/elif chains
Pipeline operator |> Not available Left-to-right filter chains
Optional chaining ?.,?[ Not available Safe navigation:obj?.attr,obj?['key']
Null coalescing ?? | default() Fallback operator:value ?? default
Fragment caching {% cache key %}...{% end %} Extension required Built-in caching directive
Functions {% def %}(lexical scope) {% macro %}(isolated) Functions see outer variables
Range literals 1..10 range(1, 11) Inclusive range syntax

Learn More

Kida Documentation

Kida is developed as a standalone template engine. For comprehensive documentation including API reference, extending the engine, and standalone usage: