rules_ios is a Bazel rule set for building Apple platform applications (iOS, macOS, tvOS, watchOS). It provides rules for creating apps, frameworks, extensions, app clips, tests, and handling Apple-specific complexities like code signing, resource bundling, and multi-architecture support. The repository integrates with rules_apple and rules_swift, offering a Bazel-native alternative to Xcode builds. Key features include automatic handling of Apple Silicon compatibility via import_middleman, VFS overlays for faster builds, and comprehensive test generation. The tooling directory contains utilities like arm64-to-sim for running arm64 binaries in x86_64 simulators and SSH password helpers for VM-based testing.