v1.18.30: every prompt fails with TypeError (undefined layer node in Effect layer assembly during SystemPrompt.environment) — works on v1.18.20

Description

Since upgrading to v1.18.30, every prompt fails with a TypeError during system-prompt assembly. The same config works perfectly on v1.18.20 (verified by A/B testing both binaries with an identical ~/.config/opencode/opencode.jsonc).

Error

TypeError: undefined is not an object (evaluating 'a.name')
    at resolve (/$bunfs/root/chunk-36bwgd4p.js:2:1659)
    at a (/$bunfs/root/chunk-36bwgd4p.js:2:936)
    at map (native:1:11)
    at <anonymous> (/$bunfs/root/chunk-36bwgd4p.js:2:1626)
    at a (/$bunfs/root/chunk-36bwgd4p.js:2:1166)
    at map (native:1:11)
    at <anonymous> (/$bunfs/root/chunk-36bwgd4p.js:2:1626)
    at a (/$bunfs/root/chunk-36bwgd4p.js:2:1166)
    at map (native:1:11)
    at <anonymous> (/$bunfs/root/chunk-36bwgd4p.js:2:1390)
    at SystemPrompt.environment (/$bunfs/root/chunk-n59f7cwr.js:50:13096)
    at SystemPrompt.environment (definition) (/$bunfs/root/chunk-n59f7cwr.js:4:14254)
    at SessionPrompt.run (/$bunfs/root/chunk-n59f7cwr.js:50:14576)
    ...

CLI output:

Error: {
  "name": "UnknownError",
  "data": { "message": "Unexpected server error. Check server logs for details.", "ref": "err_..." }
}

Analysis

• The crashing frame is Effect-TS layer-graph assembly. The bundled code contains resolve:(a)=>s.get(a.name)??a (layer-node resolution), and the crash means the visit callback received an undefined layer node — i.e. some service layer in 1.18.30 has an undefined entry in its dependencies.
• It happens during SystemPrompt.environment → location-service boot for the session directory. The log repeatedly shows booting location services.
• I could not reproduce any config dependency: the crash persists with (a) all plugins removed, (b) all MCP servers removed, (c) a fresh XDG_DATA_HOME/XDG_CONFIG_HOME, and (d) env -i with a minimal environment. This suggests the broken layer dependency is unconditional on this platform.

Reproduction

macOS 15 (Darwin 27.0.0, arm64, Homebrew install):

opencode run "say hi"   # v1.18.30 -> UnknownError; log shows the TypeError above
# same command with v1.18.20 binary -> works

Environment

• opencode 1.18.30 (Homebrew, 1.18.30_1), macOS arm64 (Apple Silicon)
• Provider: zai-coding-plan (GLM), 7 MCP servers configured
• Logs show sporadic one-off occurrences of the same error on earlier versions (~1/month since July), but v1.18.30 makes it 100% reproducible.

Happy to provide full logs or test a fix build.