Dagger Codegen

When to Load This Skill

• Editing dagger.gen.go or internal/dagger/dagger.gen.go output
• Modifying Go templates in cmd/codegen/generator/go/templates/
• Changing SDK interfaces in core/sdk.go
• Working on dagger develop, dagger call, or dagger client install
• Debugging why generated code looks wrong

Critical Concepts

"Codegen" means 4 different things in Dagger:

| # | Name | Trigger | Key Files | |---|------|---------|-----------| | 1 | In-Module Bindings | dagger develop | cmd/codegen/generator/go/templates/ | | 2 | Runtime Dispatch | Module startup | cmd/codegen/generator/go/templates/modules.go:140 | | 3 | SDK Libraries | go generate | sdk/go/generate.go | | 4 | Generated Clients | dagger client install | _dagger.gen.go/client.go.tmpl |

Know which one you're dealing with before editing.

Key Entry Points

| To change... | Edit | |--------------|------| | Generated method signatures | cmd/codegen/generator/go/templates/src/_types/object.go.tmpl | | Generated type definitions | cmd/codegen/generator/go/templates/src/_types/*.go.tmpl | | Module invoke() dispatch | cmd/codegen/generator/go/templates/modules.go:140 | | Standalone client Connect() | cmd/codegen/generator/go/templates/src/_dagger.gen.go/client.go.tmpl | | Template functions | cmd/codegen/generator/go/templates/functions.go:54 | | SDK interfaces | core/sdk.go:20 (ClientGenerator), :93 (CodeGenerator) | | Built-in SDK list | core/sdk/consts.go | | Python output | sdk/python/codegen/src/codegen/generator.py |

Reference Files

Load based on specific need:

| Need | Load | |------|------| | Understanding the 4 codegen types | codegen-types.md | | SDK architecture, interfaces, Go special case | sdk-architecture.md | | Go template conditionals, two-pass generation | go-templates.md | | dagger client install internals | generated-clients.md |