apple/swift-log

This system is the swift-log library, a logging framework for Swift that provides core logging APIs, an in-memory handler for testing, and CMake build support. It enables compile-time log level elimination to reduce binary size and overhead, while offering comprehensive benchmarking infrastructure to measure performance impacts of features like task-local loggers and metadata handling.

The build system now includes CMake modules to support Swift targets. This adds infrastructure for detecting the Swift compiler, determining the module triple, and installing Swift modules and documentation files alongside C++ artifacts, enabling users to build and install Swift components using CMake.

cmake · high confidence

A new Swift code snippet demonstrating how to import the Logging API, create a logger with a label, and log an informational message has been added to the documentation resources.

Snippets · high confidence

Added new benchmarking utilities in Benchmarks/Sources to measure logging performance. This includes a MakeBenchmark helper that configures benchmark runs with instruction and object allocation metrics, and a NoOpLogHandler that implements the LogHandler protocol to capture LogEvent and metadata attributes without producing output, enabling accurate performance measurement of logging operations.

Benchmarks/Sources · high confidence

The library now includes an InMemoryLogHandler in the InMemoryLogging module, allowing tests to capture and inspect log entries without process-wide bootstrapping. CMake build files have been added for both the Logging and InMemoryLogging modules to support CMake-based builds.

Sources · high confidence

SwiftLog introduces new package traits (MaxLogLevelDebug through MaxLogLevelNone) that allow developers to eliminate unused log levels at compile time, reducing binary size and overhead. This feature is available starting with Swift 6.1 and is configured via the [e-mail redacted] manifest, enabling users to tailor logging verbosity to their specific needs without runtime cost.

(repo-wide) · high confidence

Add benchmark suite for MaxLogLevelNone optimization; Added benchmarks for task-local loggers and metadata sensitivity; Added tests for InMemoryLogHandler; Added tests for the new Swift Testing framework migration and logging API compatibility.

The package now requires Swift 6.2 and introduces compile-time log level traits (MaxLogLevelNone through MaxLogLevelDebug) that allow users to strip unused log levels from the binary at build time. The package name has changed to swift-log, exposing Logging and InMemoryLogging products, and enables strict concurrency and upcoming compiler features for improved type safety.

(dependencies) · high confidence

Written by watchdog.canine.dev from the codebase's own history, inside the signed delivery this page is composed from.

• CAI 65 → 63 (-1.7)
• Rubric changed (rubric-2026.09.11 → rubric-2026.09.18) — scores are not directly comparable.

• Code Health 98 → 98 (-0.6)
• Architecture 100 → 96 (-3.7)
• Maturity 58 → 57 (-0.4)
• Readiness 61 → 65 (+4.1)
• Security 61 → 61 (+0.0)
• Performance 73 (new)

• Documentation: no installation or build instructions (README.md)
• Documentation: no usage examples (README.md)
• Off-boarding risk: anonymized user #1

• Dependency hygiene PARTLY measured — SwiftPM pinning read, dependency currency NOT established
• MultiplexLogHandler.metadataProvider (cognitive 21) (Sources/Logging/Handlers/MultiplexLogHandler.swift)
• No Package.resolved committed (Benchmarks/MaxLogLevelNone/Package.swift)
• No Package.resolved committed (Benchmarks/MaxLogLevelWarning/Package.swift)
• No Package.resolved committed (Benchmarks/NoTraits/Package.swift)
• Off the main sequence: Logging
• Off-boarding risk: anonymized user #1
• Redundant logging entry points: The LogHandler protocol exposes both a high-level 'event' based method and a low-level parameterized method. While this allows flexibility, it creates ambiguity for implementers (e.g., InMemoryLogHandler, StreamLogHandler) who must implement both, often leading to code duplication or delegation patterns that are not explicitly enforced by the protocol structure.
• Verbosity vs. Convenience: The Logger exposes both a generic 'log(level:)' method and specific convenience methods for each log level. While this is a common pattern, it duplicates the intent of 'logging a message' across 9 different method names. For API consistency, users must choose between using the generic method with an enum or the specific methods, which can lead to inconsistent usage patterns within a codebase.

• 3 commits — 2 feature/other, 1 fixes

• (root) — 2 commits
• Benchmarks/NoTraits — 1 commit

• fix: Fix nested metadata values handling (#516)
• change: Remove invalid exclude statements from testTarget (#514)
• change: Update stale package names and broken ordo-one/benchmark documentation links (#511)

Written by watchdog.canine.dev from the codebase's own history, inside the signed delivery this page is composed from.

apple/swift-log was measured the same way every project in this corpus was: the same rubric, at a pinned commit, with the result published in full. Point a surveyor at a repository you know and see whether you agree with it.