diff --git a/BUILDING.md b/BUILDING.md
index 6f5d067..fec8114 100644
--- a/BUILDING.md
+++ b/BUILDING.md
@@ -8,8 +8,8 @@ Scarf is a native macOS app built with Xcode. For contributor builds, use the lo
 
 Requirements:
 
-- macOS 26.2 or newer (the app's deployment target)
-- Xcode 26.2 or newer, selected by `xcode-select`
+- macOS 14.6 (Sonoma) or newer at runtime — that's the app's `MACOSX_DEPLOYMENT_TARGET`. Sonoma support is intentional and load-bearing; do not raise this without an explicit decision to drop Sonoma users
+- Xcode 16.0 or newer, selected by `xcode-select` (needed for Swift 6 strict-concurrency features the project uses)
 - Metal toolchain installed
 - Hermes installed at `~/.hermes/` (see the project README for setup)
 
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index d51b4ec..d26a238 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -5,8 +5,8 @@ Thanks for your interest in contributing to Scarf.
 ## Getting Started
 
 1. Fork and clone the repo
-2. Open `scarf/scarf.xcodeproj` in Xcode 26.3+
-3. Build and run (requires macOS 26.2+ and Hermes installed at `~/.hermes/`)
+2. Open `scarf/scarf.xcodeproj` in Xcode 16.0+
+3. Build and run (Scarf runs on macOS 14.6 Sonoma or newer; Hermes must be installed at `~/.hermes/`)
 
 For an unsigned command-line Debug build without an Apple Developer account, run [`./scripts/local-build.sh`](scripts/local-build.sh). See [BUILDING.md](BUILDING.md) for prerequisites.