Go Code Generation Patterns

Code generators produce Go source files from templates, AST manipulation, or a combination. The key principle: manipulate Go as a structured program, not as text.

When to Use

• Writing or editing a code generator or scaffold tool
• Authoring Go templates (*.go.tmpl)
• Designing a YAML-driven manifest or block schema
• Adding AST injection to a generator pipeline
• Writing golden-file tests for generated output
• Debugging injection failures or template rendering errors

AST Over String Edit

Never build generated Go source with strings.Replace or template string concatenation — it's fragile and breaks on formatting changes: