Only the latest release is supported. Older releases receive no security updates — download the newest OpencodePortable.exe from Releases.

• This launcher isolates files (config, cache, temp, binary) and cleans them up on exit. It is not a sandbox: opencode runs with your user permissions and can execute shell commands in the workspace.
• Use trusted workspaces only: local folders, not shared/synced/untrusted locations. Anyone who can write the workspace can influence what runs.
• The per-run root inherits the workspace ACLs: on a shared drive or a synced folder, other people may read live credentials. Never use shared/synced locations for sessions with secrets; prefer a local, single-user folder.
• --clean-host removes our WER/watchdog/crash/update leftovers but may need admin for %ProgramData% archives; a standard user can only clean their own profile. Exit code stays 0 with a skipped count — read the output. It never touches the opt-in <exe>/auth/ dir: credentials are never deleted silently, use --forget-auth for explicit logout.
• Self-updater: explicit --check-update / --update only; normal runs never use the network. Updates check our own portable releases over HTTPS, verify the release .sha256 fail-closed (missing/mismatch aborts), never send tokens in argv, stage .new.exe for a detached replace (the running exe is locked on Windows). Review the output before restarting.
• Persistent auth (--persist-auth) is bearer tokens at rest next to the exe: BitLocker-encrypt portable drives; a lost stick means lost credentials until you revoke the key from opencode.ai/console. --forget-auth wipes it.
• Lost or stolen media means lost credentials: BitLocker-encrypt portable drives and dismount them; EFS is not portable across machines.
• "Cleanup" removes application files and known runtime artifacts (see README checklist). It is not forensic anti-tracking: OS and security telemetry (Prefetch, Defender/SmartScreen, USN Journal, shell history, antivirus logs) cannot be removed by any portable app.
• No login or credentials are stored by the launcher itself, except the explicit opt-in <exe>/auth/ (--persist-auth) and the scripts' data/ (which persists opencode auth login state by design). Provider API keys stay per-session via env (e.g. OPENCODE_API_KEY); never share data/, .opencode-portable-*/ or <exe>/auth/ folders. Lost media = revoke the key from opencode.ai/console and rotate.
• External providers (NVIDIA, Anthropic, OpenAI, …) are untested with this project. No warranty on provider setups.

Do not open a public issue for security problems. Instead:

1. Go to the repository → Security tab → Report a vulnerability (private security advisory, visible only to maintainers), and describe:
   • affected version / commit
   • steps to reproduce
   • what an attacker could achieve (what data, whose machine)
   • whether it needs local access, a malicious workspace, or network
2. Expect an acknowledgement (best effort — this is a personal project, no SLA, no bug bounty). Critical issues affecting the current release (arbitrary deletion outside the workspace, silent execution of untrusted binaries) are prioritised: fix + new release + CHANGELOG entry.
3. Out of scope (will be closed as such): upstream opencode vulnerabilities (report to upstream), SmartScreen warnings on the unsigned build, missing Authenticode signature, social-engineering scenarios, physical access.

if ((Get-FileHash OpencodePortable.exe -Algorithm SHA256).Hash.ToLower() -ne (Get-Content OpencodePortable.exe.sha256)) { throw 'hash mismatch' }

The .sha256 is published next to the .exe in every release. This proves the download is intact — not authorship (no Authenticode signature yet).