[youfun]

Follows the plan in build_system_migration.md: the 0.17.0-dev.269+ebff43698 nightly existed because Zig 0.15.x could not link on the macOS 26 SDK. 0.17.0 is that stable.

This is one change across three repos (same branch name zig-0.17.0):

• mob (this PR): pin + std.fmt.bufPrintZ → bufPrintSentinel in android/jni/mob_nif.zig
• mob_dev: pin in MobDev.Toolchain + doctor fails stale iOS b.build_root
• mob_new: pin + iOS templates glob Swift with std.Io.Dir.openDirAbsolute

mix mob.doctor still requires an exact zig version match (mise install zig@0.17.0).

What was verified on host (Zig 0.17.0)

• zig ast-check on Mob Zig sources
• zig build-obj -target aarch64-linux-android.24 for mob_nif.zig after the bufPrintSentinel change (and several sibling files that needed no edits)
• zig build --help configure of current Android build.zig and of the updated iOS sim/device templates
• Unfixed iOS templates fail configure with no field named 'build_root'

Not verified

• Full native-lib / iOS binary link (no NDK sysroot / OTP tarball / device SDK in this run)
• mix mob.deploy --native on Android or iOS
• Runtime on a device or simulator

Existing apps must upgrade mob + mob_dev + app-owned iOS build.zig together. Android build.zig from current templates already configures on 0.17.0.

No Linear MOB-N (no API access from this contributor).

[youfun]

Companion PRs: GenericJam/mob_dev#146 and GenericJam/mob_new#107

[GenericJam]

Maintainer update. I rebased this onto current master and added commits on top; thanks @youfun.

Added on top of the original change

• Rebased over the OTP 29.1.2 release; .tool-versions keeps erlang 29.1.2.
• Further 0.17.0 API fixes: std.mem.printSentinel (the stdlib marks bufPrintSentinel deprecated) and dupeSentinel in place of the removed dupeZ in mob_stored_queue.zig.
• iOS templates: the Swift glob now calls b.dependOnDirectoryContents on mob/ios. Zig 0.17.0 caches the configure step, so without that a Swift file mob adds is missed until the Zig cache is cleared. I reproduced this; a regression test now builds twice with one cache.
• mob.doctor: fails a glob that still uses b.build_root and warns when the glob is not tracked. It ignores comments and strings.
• CI runs the pinned Zig, read from .tool-versions or priv/zig-version:
  • mob compiles mob_nif.zig for Android and runs every Android Zig test.
  • mob_dev has a macOS job for :requires_zig.
  • mob_new has a macOS job for the generated build.zig link tests.
• CHANGELOG upgrade steps: mise use zig@0.17.0 in each app, and the iOS glob block.

Checked on real devices with Zig 0.17.0, using an app generated from the three branches. mix mob.deploy --native worked on all three: the Moto G (Android arm64) and the iPhone 17 simulator booted and rendered the home screen, and the physical iPhone SE built and launched.

Review

• Codex rounds 1–3: DO NOT SHIP. Every finding is fixed.
• Round 4 went to a reviewer subagent, because Codex was usage-limited: SHIP. Its nitpicks are fixed.