Nebula 3.0.0-alpha.5

Nebula 3.0.0-alpha.5

Nebula 3.0.0-alpha.5 supersedes the unpublished alpha.2, alpha.3, and alpha.4
candidates. It narrows the protected release surface to Linux x86_64 while the
macOS distribution path is redesigned and validated independently.

Changes since alpha.1

• The protected release workflow now produces Linux x86_64 artifacts only.
• The direct AppImage includes signed updater metadata and rejects tampered
  artifacts during release validation.
• The managed DEB omits the direct updater and is tested on clean Ubuntu 24.04,
  Debian 12, and Kali rolling containers.
• Release draft creation validates the preparation run, embedded commit,
  version, target, distribution channel, artifact set, SBOMs, and checksums.
• The packaged desktop self-test gives Nebula Core a bounded graceful-shutdown
  window before falling back to process-group signals.
• Tall terminal screenshots can fit completely inside the image editor at zoom
  levels below ten percent without enlarging smaller images.
• Diagnostics, container-terminal, and UI release tests synchronize on
  observable state and use bounded timeouts.

There are no intentional engagement-data format changes from alpha.1. No
alpha.2, alpha.3, or alpha.4 release was published.

Native packages

The release workflow stages the following artifacts for manual review:

• a Linux x86_64 AppImage for direct distribution; and
• a Linux x86_64 DEB for managed distribution.

Direct builds can consume Nebula's signed updater channel. Managed builds omit
the direct updater so deployment remains under administrator control. macOS,
Windows, and Linux arm64 packages are not included in this alpha.

Docker or Podman is required for terminal and automation features. A model
provider is optional; the human terminal, evidence workflow, notes, findings,
and reports remain usable without one.

Alpha limitations

• This is a prerelease and may contain compatibility defects or incomplete UX.
• Engagement bundle export is integrity-manifested, but this alpha does not yet
  provide a bundle restore path.
• Terminal and automation availability depends on a compatible local container
  runtime and its networking configuration.
• Local and hosted model capabilities vary. Nebula enables structured tools
  only after the selected provider/model passes its verification contract.

After installation

Launch the desktop with nebula. Confirm the bundled Core and local runtime
boundary before beginning an engagement:

nebula-core doctor --json

Report defects with the exact version, platform, failed action, correlation ID,
and a Diagnostics support bundle after reviewing it for sensitive engagement
data.