Ship to GitHub Releases, S3, or any HTTP host — and to every major desktop store.

Once your installers are signed, you need somewhere to put them and an audience to reach. Nucleus wires three publishing backends into the same Gradle DSL — GitHub Releases, S3, and generic HTTP — and the resulting metadata feeds the auto-updater. For store channels, this page collects what each store wants: Mac App Store, Microsoft Store, Snapcraft, Flathub.

TL;DR

publish { github / s3 / generic } configures hosting for installers + update YAML.
PublishMode.Auto publishes from CI, skips locally — sane default.
Three release channels (Latest, Beta, Alpha) and three release types (Release, Draft, Prerelease).
Store submissions: each ecosystem has its own portal (Partner Center, App Store Connect, Snapcraft.io, Flathub PRs).

Install

Comes with the Gradle plugin.

Quickstart

nucleus {
    application {
        nativeDistributions {
            publish {
                publishMode = PublishMode.Auto

                github {
                    enabled = true
                    owner = "myorg"
                    repo = "myapp"
                    token = System.getenv("GITHUB_TOKEN")
                    channel = ReleaseChannel.Latest
                    releaseType = ReleaseType.Release
                }
            }
        }
    }
}

How it works

GitHub Releases (recommended)

A release ends up looking like this, with auto-update YAMLs alongside the installers:

v1.0.0 (Release)
├── MyApp-1.0.0-macos-arm64.dmg
├── MyApp-1.0.0-macos-universal.dmg
├── MyApp-1.0.0-windows-amd64.exe
├── MyApp-1.0.0-windows.msixbundle
├── MyApp-1.0.0-linux-amd64.deb
├── MyApp-1.0.0-linux-amd64.AppImage
├── latest-mac.yml
├── latest.yml
└── latest-linux.yml

The GITHUB_TOKEN needs contents: write — in GitHub Actions, set permissions: contents: write on the job.

S3

For self-hosted distribution with a CDN-backed bucket:

publish {
    s3 {
        enabled = true
        bucket = "my-updates-bucket"
        region = "us-east-1"
        path = "releases/myapp"
        acl = "public-read"
    }
}

Set AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY, AWS_REGION in the environment.

Generic HTTP

Any static host (Nginx, Caddy, Cloudflare R2, S3 with public access). The plugin generates YAML metadata configured for a base URL; you upload yourself.

publish {
    generic {
        enabled = true
        url = "https://updates.example.com/releases/"
        channel = ReleaseChannel.Latest
        useMultipleRangeRequest = true
    }
}

Channels and types

Channel	YAML	Tag pattern
`ReleaseChannel.Latest`	`latest-*.yml`	`v1.0.0`
`ReleaseChannel.Beta`	`beta-*.yml`	`v1.0.0-beta.1`
`ReleaseChannel.Alpha`	`alpha-*.yml`	`v1.0.0-alpha.1`

Type	Behavior
`ReleaseType.Release`	Public on the releases page
`ReleaseType.Draft`	Hidden until manually published
`ReleaseType.Prerelease`	Marked pre-release

Publish modes

PublishMode.Never — build only.
PublishMode.Auto — publish if on CI, skip locally.
PublishMode.Always — always publish.

`publish { }` only generates config

The block writes electron-builder publisher settings. The actual upload is performed by the CI workflow (gh release create for GitHub, aws s3 cp for S3, your own copy for generic). The release CI wires the standard path.

Store submissions

Mac App Store — submit the PKG via Transporter or xcrun altool. Provisioning profiles (sandboxing) and the App Store category (appCategory) are baked in at build time. Apple reviews; no notarization is needed for App Store builds.

Microsoft Store — upload the .msixbundle to Partner Center. Identity must match the reservation (identityName, publisher = CN=<GUID>, publisherDisplayName) — see Windows targets. MinVersion must be > 10.0.17134.0.

Snapcraft — snapcraft upload from CI. The Snap Store accepts strict and classic confinement; classic requires approval. See linux.snap { grade = SnapGrade.Stable }.

Flathub — submit a manifest PR to the Flathub repo. Your build's flatpak block already produces the right .flatpak bundle; Flathub builds from source via your manifest.

GitHub Releases / direct download — the default. Pair with auto-update for self-distributed apps.

Reference

publish { publishMode = … }
publish.github { enabled, owner, repo, token, channel, releaseType }
publish.s3 { enabled, bucket, region, path, acl }
publish.generic { enabled, url, channel, useMultipleRangeRequest }
enum class PublishMode { Never, Auto, Always }
enum class ReleaseChannel { Latest, Beta, Alpha }
enum class ReleaseType { Release, Draft, Prerelease }

Full reference: Gradle DSL reference.

Notes

Tip: base64-encode signing certs and store them as CI secrets, decode at build time. See code signing for the macOS and Windows playbooks.
The generic provider supports useMultipleRangeRequest for differential downloads — only useful if your HTTP server honors Range requests.
For 2.x prereleases, the convention is to cut tags from the nucleus-2.0 branch with v2.x.y-alpha-*, -beta-*, or -rc-* patterns. CI validates the tag points to a commit on that branch.

Publishing