Real CLI proof: built each checkout using vp i and vp run build:bundle in apps/server. Run: python3 prove-proxy.py BASE_CHECKOUT HEAD_CHECKOUT NEW_OUTPUT_DIRECTORY
Linux user+mount+network namespaces isolate all network changes. A Unix-socket relay connects a namespace HTTP proxy to real GitHub. /etc/hosts overrides are namespace-only. Direct GitHub TLS sockets receive TCP resets in the primary comparison. TLS is never intercepted; archive checksums and the downloaded executable are validated by the real CLI.
Primary comparison: HTTPS_PROXY alone; HTTP_PROXY, NODE_OPTIONS, NODE_USE_ENV_PROXY and lower-case proxy variables unset. NO_PROXY=unrelated.invalid. Both use a fresh isolated T3 home. The real nightly release is newer than 0.1.8.
Additional head-only cases: NO_PROXY=github.com permits direct GitHub sockets through a separately labeled transport bridge; the asset redirect remains proxied. Loopback case sets HTTP_PROXY too and points the supported release mirror variable at a loopback redirect server; its two HTTP requests are observed directly.
PNG and MP4 files are rendered terminal playbacks from timestamped captured stdout/network observations, not screenshots of a GUI. CAST files preserve the timestamped text. Route logs are appended after each command completes. Private checkout and home paths were replaced with placeholders. All four final outputs and video contact sheets were visually inspected.
Initial attempts downloaded successfully but extraction failed because tar tried to restore archive ownership inside a user namespace. All final runs use TAR_OPTIONS=--no-same-owner identically.
No tests were used as proof. No provider turns or background-service restarts were performed.
AI-assisted; verified with the tests and tools listed above.

Final primary comparison and NO_PROXY case use run 04; final loopback case uses run 05 with the exact discovered release version, avoiding unrelated release-index availability. A transient release-list failure in run 04 supplemental loopback is retained in the raw log. Final recorder queries Node from the CLI checkout; earlier recorder metadata reported its launcher Node instead.
