Syn-Syu is Synavera's conscious successor to pacman -Syu. A Bash orchestrator (syn-syu) works together with a Rust backend (synsyu_core) to build a manifest of the current system state (installed packages with source), build update plans from fresh sources, apply repo/AUR/app/firmware updates selectively, and produce detailed logs for review.

Syn-Syu is source-aware and tool-aware. Different channels may use different bounded recovery strategies; pacman mirror failover is not treated as a generic solution for AUR helpers, PKGBUILD sources, Flatpak, or fwupd.

• Coordinates pacman and AUR helpers with explicit include/exclude filters.
• Generates a JSON manifest via synsyu_core as the authoritative state, plus update plans from fresh sources (pacman, AUR, optional Flatpak/fwupd).
• Captures install metadata (install date, validation root, truncated package or firmware hashes) for audit-friendly manifests and plans without leaking full fingerprints.
• Configurable logging level with time and size-based log retention policies.
• Validates download, build, and install footprint before updates, applying a configurable free-space buffer.
• Applies source-aware bounded acquisition policy: pacman repos use mirror failover, AUR RPC/helper paths use transient retry where safe, and other channels remain tool-owned unless explicitly implemented.
• Optional application updates for Flatpak and firmware (fwupd) with dedicated commands or opt-in flags that now also seed the manifest and plan.
• Supports guided or advanced install workflows through optional tooling.
• Logs every action with timestamped entries to simplify auditing.
• Provides commands for sync, targeted updates, group operations, cleaning, and inspection, planning, and helper selection.

See docs/Syn-Syu_Overview.md for a deeper walkthrough of the architecture and CLI behaviour.

The repository ships with a ready-to-build PKGBUILD.

git clone https://github.com/Synavera-Discorporated/Syn-Syu.git
cd Syn-Syu
makepkg -sif

This installs:

• /usr/bin/syn-syu (Bash orchestrator)
• /usr/bin/synsyu_core (Rust backend)
• /usr/lib/syn-syu/*.sh (helper libraries)
• /usr/share/doc/syn-syu/ (documentation and examples)

If you prefer to install outside of pacman, use the helper script:

./tools/install_syn-syu.sh

The wizard can perform a guided install, build synsyu_core in release mode, and copy binaries and libraries into a prefix you choose. An accompanying tools/uninstall_syn-syu.sh script safely removes the same assets.

Syn-Syu looks for configuration at ~/.config/syn-syu/config.toml. An example file is provided at examples/config.toml. You can view the merged configuration with synsyu_core config [--json]; log retention pruning is available through synsyu_core logs --prune. Key options include:

• core.manifest_path – output path for the generated manifest.
• space.min_free_gb – reserved buffer that must remain free after updates.
• space.mode – "warn" (default) logs a warning if free space is below the buffer; "enforce" fails the plan when the buffer is not met.
• logging.level – choose from debug, info, warn, error, or none.
• logging.retention_days / logging.retention_megabytes – prune old logs by age or aggregate size.
• logging.directory – explicit log location (falls back to core.log_directory for compatibility).
• helpers.priority – ordered list of AUR helpers to try.
• aur.max_parallel_requests / aur.max_kib_per_sec – control how many AUR RPC calls run concurrently and optionally throttle each request in KiB/s.
• mirrors.enabled – enables mirror-aware repo acquisition failover.
• mirrors.mirrorlist_path / mirrors.pacman_conf_path – inputs used to read mirror candidates and build temporary pacman configs without editing system files.
• mirrors.probe, mirrors.probe_timeout_seconds, mirrors.max_candidates, and mirrors.max_sync_age_hours – bound mirror probing and stale-mirror filtering.
• mirrors.cache_ttl_hours / mirrors.cache_path – keep last-known probe outcomes so the next rebuild can choose better first candidates before it probes again.
• mirrors.max_failovers / mirrors.retry_delay_seconds – bound repo acquisition retries; attempts are limited to max_failovers + 1.
• acquisition.aur_rpc.* – bounded transient retry for direct AUR RPC calls used by synsyu_core.
• acquisition.aur_helper.* – bounded transient retry around AUR helper acquisition failures; build, dependency, signature, checksum, and PKGBUILD failures are terminal.
• applications.flatpak / applications.fwupd – defaults for including application/firmware updates in both manifest generation and sync (also exposed as commands and --with-* flags).
• snapshots.* – optional pre/post commands for snapshot integrations.
• safety.disk_check / safety.disk_extra_margin_mb – enable disk guards and define additional safety margin before installs proceed.

CLI flags such as --config, --include, --exclude, --dry-run, --no-aur, --no-repo, --mirrors, --no-mirrors, and --min-free-gb override configuration on demand.

Mirror failover does not replace pacman trust, signature, dependency, or transaction checks. Syn-Syu only cycles mirrors after retrieval-style failures such as timeouts or failed downloads. Signature, integrity, keyring, dependency, lock, disk, and conflict errors stop the mirror loop and are surfaced as final failures. Known-fresh mirrors are ranked ahead of mirrors whose freshness cannot be checked; stale mirrors are excluded from failover candidates. Syn-Syu creates temporary pacman config files for each attempt and does not permanently modify your system mirrorlist. Mirror status output includes a short outcome code such as ready, stale, timeout, connect_failed, or http_error.

Syn-Syu is source-aware and tool-aware. Pacman mirror failover is pacman-specific. AUR RPC retry covers transient HTTP/network failures in Rust state generation. AUR helper retry covers clearly transient helper fetch/clone/download failures in Bash execution. PKGBUILD upstream source fallback, Flatpak retry policy, and fwupd retry policy are not implemented as Syn-Syu strategies yet; those channels remain separate future extension points or tool-owned behavior. For AUR RPC, [acquisition.aur_rpc].max_retries wins when set; legacy [aur].max_retries is used only when the new acquisition key is absent.

Common entry points (both syn-syu and synsyu work):

synsyu            # Sync repo metadata, rebuild manifest, prompt for updates
synsyu --dry-run  # Preview updates without making changes
synsyu plan       # Build an update plan JSON (no installs)
synsyu update <pkg>...
synsyu group <name>
synsyu clean
synsyu aur        # AUR-only updates
synsyu repo       # Repo-only updates
synsyu apps       # Run flatpak + fwupd update flows together
synsyu core --with-flatpak --with-fwupd  # record Flatpak/firmware intent in manifest
synsyu flatpak    # Apply Flatpak updates (or dry-run list)
synsyu fwupd      # Apply firmware updates via fwupdmgr
synsyu sync --with-flatpak --with-fwupd  # include app/firmware updates in one sweep
synsyu helpers    # List detected AUR helpers
synsyu helper <name>  # Set helper for this session (or persist with helpers.sh)
synsyu self-update # Clone GitHub and reinstall Syn-Syu via makepkg
synsyu mirrors    # Show ranked mirror candidates recorded in the manifest
synsyu acquisition # Show source-aware bounded acquisition policy
synsyu config     # Show config path info
synsyu groups-edit  # Open groups.toml in $EDITOR
synsyu log        # Show log directory/retention info
synsyu version    # Show version/build info
synsyu help       # Usage help

Common aliases are available for frequent flags: -v for --verbose, -c for --confirm, -nc for --noconfirm, -w-fp for --with-flatpak, and -w-fw for --with-fwupd.

Use syn-syu --help for the full command set, including manifest inspection, logging, and AUR-only or repo-only operations.

Until Syn-Syu is published through a package repository, syn-syu self-update can update Syn-Syu from GitHub. It clones https://github.com/Synavera-Discorporated/Syn-Syu.git into a temporary build directory and runs the repository PKGBUILD with makepkg -sif, preserving pacman ownership instead of overwriting installed files directly. Use syn-syu self-update --dry-run to preview the operation. Advanced testers can override the source with SYN_SYU_SELF_UPDATE_REPO and SYN_SYU_SELF_UPDATE_REF.

The Rust binary is also available directly:

synsyu_core --manifest ~/.config/syn-syu/manifest.json --with-fwupd --offline
synsyu_core plan --manifest ~/.config/syn-syu/manifest.json --plan ~/.config/syn-syu/plan.json --json --strict
synsyu_core mirrors --no-probe --json

The Rust backend lives in synsyu_core/ and is vendored directly into this repository. Useful commands:

cargo fmt
cargo clippy --all-targets --all-features
cargo test
cargo build --release

Bash code follows the Synavera Script Etiquette guidelines (see docs/). Contributions should include appropriate logging and remain shellchecked where possible.

For a formal description of Syn-Syu’s capabilities and safety guarantees, see docs/synspek.yaml (capabilities) and docs/synspek_checks.yaml (test charter).

Apache License 2.0. Arch packages use the common license from the licenses package. See your system’s common licenses directory or the official text: https://www.apache.org/licenses/LICENSE-2.0