[antoinetoussaint-byte]

Go service bases are hardcoded in the emitted Dockerfile, so an environment cannot select approved replacement content. Implement Core's optional base-image-bindings/v1 contract: advertise frontend, builder and runtime roles from loaded settings; validate immutable bindings; render the selected references through the existing template.

Static and native services expose the same runtime image input, so one type-wide default covers both. Static services use that input for assembly and keep scratch final stages. CGO or runtime packages retain the Alpine/musl final recipe. Unsupported roles/variants refuse. The default Go builder pin moves from 895e5fea to current upstream 8a504649; runtime Alpine remains pinned 3.23.7/ff7f0c. No owner release, service pin, installed agent or deployed image changes.

Fix at the owner: reuses live BuildCapabilities, Core binding validation, the template, Build RPC and maintained packaging test. Core source dependency is normally pinned from codefly-dev/core#874 using codefly agent deps --pin, including owned factory/base locks. CLI support is codefly-dev/cli#1232. Related existing plan: obin-ai/infra-base#1485.

Docs: templates/agent/README.md.tmpl explains roles, precedence, native compatibility and qualification limits; docs/service-protocol.md records the gateway dependency compatibility change.

Validation: focused template/recipe/binding race tests and real Build gRPC test pass; vet and factory-lock check pass. Maintained packaging CI adds selected-static and selected-native cases to the existing four-case native amd64/arm64 matrix; these execute digest-only bindings through the production Build RPC, retain archives and Syft inventory, and preserve strict runtime/temp/home/native checks and exact owned cleanup. Both native packaging jobs pass at final 520c8bc in run 40905091378 (six cases each); artifact IDs 12912075288 (arm64) and 12910677836 (amd64) retain archives/inventories. Real CLI consumer builds also pass with type and service overrides, runtime execution, cache invalidation/reuse and incompatible-variant refusal. All five final agent checks pass, including the full general suite.

The Core dependency update selects grpc-gateway 2.33, whose secure default no longer forwards arbitrary Grpc-Metadata-* headers. The proxy regression initially failed against that default; its fixture now explicitly maps only X-Caller through the existing ServeMuxOptions seam. The same generated-service adapter suite passes without restoring legacy header matching. Native candidate scan retains two unpatched Docker HIGH findings; no release or universal CVE clearance claim.