Airspeed review

Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

Airspeed is an open-source Python templating engine for developers who want to render Velocity-style templates from Python. It can suit small teams prototyping with Velocity templates or replacing Java code that uses Velocity. Templates are rendered by calling the library from Python code, with support for variable interpolation, conditional and loop directives, macros, and template inclusion or parsing. Its logic-based syntax model makes it a fit for template work that needs these control structures rather than simple variable substitution alone.

The core feature set covers common template composition needs: #if conditionals, #foreach loops, #macro definitions, and #include and #parse directives. A caching file loader is included, and the project describes templates as Unicode-safe. Airspeed's compatibility with Velocity is substantial, but not complete; the project also notes that rendered whitespace does not fully match Velocity. That distinction matters for teams replacing existing templates, especially where output formatting depends on whitespace. It is better suited to projects that can accommodate compatibility differences than to a drop-in replacement requirement.

Airspeed is free and open source, so its pricing model does not introduce paid tiers to weigh against the feature set. The project describes compatibility with Python 2.7 and later, including Jython. That makes it relevant to Python applications or prototypes drawing on Velocity conventions, but the product is a library called from Python code rather than a broader template platform. Small teams seeking a lightweight, no-cost engine with familiar Velocity-style directives should consider it; teams requiring complete Velocity behavior or exact whitespace parity should look for an alternative.

Airspeed pros and cons

• Where it wins
  • Supports interpolation, conditionals, loops, and macros
  • Includes and parses templates, with a caching file loader
  • Unicode-safe templates and an open-source model
• Where it doesn't
  • Velocity compatibility is substantial but not complete
  • Rendered whitespace may differ from Velocity
  • Designed for Python rendering, not a broad platform ecosystem

Airspeed fact sheet, pricing and score →

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Last updated 29 Oct 2026 · How we research and update