diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 7ec564b4..1df3d9d8 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -22,7 +22,7 @@ jobs:
   build-macos:
     name: Build and Test (macOS)
     runs-on: macos-15
-    timeout-minutes: 30
+    timeout-minutes: 75
 
     steps:
       - name: Checkout code
@@ -59,7 +59,7 @@ jobs:
             --skip LargeBlock \
             --skip EndToEnd \
             --skip ClientServer
-        timeout-minutes: 20
+        timeout-minutes: 60
 
       - name: Build (release)
         run: swift build -c release
diff --git a/.github/workflows/code-quality.yml b/.github/workflows/code-quality.yml
index f4b72b27..56178c12 100644
--- a/.github/workflows/code-quality.yml
+++ b/.github/workflows/code-quality.yml
@@ -80,7 +80,7 @@ jobs:
   code-coverage:
     name: Code Coverage
     runs-on: macos-15
-    timeout-minutes: 30
+    timeout-minutes: 75
 
     steps:
       - name: Checkout code
@@ -103,7 +103,7 @@ jobs:
             --skip LargeBlock \
             --skip EndToEnd \
             --skip ClientServer
-        timeout-minutes: 20
+        timeout-minutes: 60
 
       - name: Generate coverage report
         run: |
diff --git a/.github/workflows/conformance.yml b/.github/workflows/conformance.yml
index 0653a118..731c0ce0 100644
--- a/.github/workflows/conformance.yml
+++ b/.github/workflows/conformance.yml
@@ -22,7 +22,7 @@ jobs:
   part1-conformance:
     name: Part 1 (Core) Conformance
     runs-on: macos-15
-    timeout-minutes: 30
+    timeout-minutes: 75
 
     steps:
       - name: Checkout code
@@ -61,7 +61,7 @@ jobs:
   part2-conformance:
     name: Part 2 (Extensions) Conformance
     runs-on: macos-15
-    timeout-minutes: 30
+    timeout-minutes: 75
 
     steps:
       - name: Checkout code
@@ -99,7 +99,7 @@ jobs:
   part3-part10-conformance:
     name: Part 3 (MJ2) and Part 10 (JP3D) Conformance
     runs-on: macos-15
-    timeout-minutes: 30
+    timeout-minutes: 75
 
     steps:
       - name: Checkout code
@@ -137,7 +137,7 @@ jobs:
   part15-conformance:
     name: Part 15 (HTJ2K) Conformance
     runs-on: macos-15
-    timeout-minutes: 30
+    timeout-minutes: 75
 
     steps:
       - name: Checkout code
@@ -175,7 +175,7 @@ jobs:
   part4-conformance:
     name: Part 4 (Conformance Final) Validation
     runs-on: macos-15
-    timeout-minutes: 30
+    timeout-minutes: 75
 
     steps:
       - name: Checkout code
@@ -213,7 +213,7 @@ jobs:
   jp3d-conformance:
     name: Part 10 (JP3D) Conformance
     runs-on: macos-15
-    timeout-minutes: 20
+    timeout-minutes: 75
 
     steps:
       - name: Checkout code
diff --git a/.github/workflows/dicomkit-downstream.yml b/.github/workflows/dicomkit-downstream.yml
index 48e81188..383cb122 100644
--- a/.github/workflows/dicomkit-downstream.yml
+++ b/.github/workflows/dicomkit-downstream.yml
@@ -31,7 +31,7 @@ jobs:
   dicomkit-build:
     name: DICOMKit builds against J2KSwift HEAD
     runs-on: macos-15
-    timeout-minutes: 25
+    timeout-minutes: 75
 
     steps:
       - name: Checkout J2KSwift (this PR / commit)
@@ -100,7 +100,7 @@ jobs:
         run: |
           cd DICOMKit
           swift build
-        timeout-minutes: 15
+        timeout-minutes: 30
 
       - name: Run DICOMKit curated test set
         # Excludes 9 pre-existing unrelated failures (see CROSS_CODEC_DICOM_REPORT.md):
@@ -119,5 +119,5 @@ jobs:
             --skip "DICOMXML" \
             --skip "test_allocateBlock_allocatesFirstBlock" \
             --skip "WorkitemBuilder/testRoundTripWithSequences"
-        timeout-minutes: 20
+        timeout-minutes: 60
         continue-on-error: true
diff --git a/.github/workflows/interactive-testing.yml b/.github/workflows/interactive-testing.yml
index 6f8c2e8d..5cf2add7 100644
--- a/.github/workflows/interactive-testing.yml
+++ b/.github/workflows/interactive-testing.yml
@@ -40,7 +40,7 @@ jobs:
   headless-tests:
     name: Headless Test Run (${{ github.event.inputs.playlist || 'Quick Smoke Test' }})
     runs-on: macos-15
-    timeout-minutes: 30
+    timeout-minutes: 75
 
     steps:
       - name: Checkout code
diff --git a/.github/workflows/jp3d-compliance.yml b/.github/workflows/jp3d-compliance.yml
index 2ce33fb3..a47a244d 100644
--- a/.github/workflows/jp3d-compliance.yml
+++ b/.github/workflows/jp3d-compliance.yml
@@ -30,7 +30,7 @@ jobs:
   jp3d-compliance:
     name: JP3D Part 4 Compliance Tests
     runs-on: macos-15
-    timeout-minutes: 20
+    timeout-minutes: 75
 
     steps:
       - name: Checkout code
diff --git a/.github/workflows/performance.yml b/.github/workflows/performance.yml
index f15aacf2..3b67df0e 100644
--- a/.github/workflows/performance.yml
+++ b/.github/workflows/performance.yml
@@ -22,7 +22,7 @@ jobs:
   benchmark-macos:
     name: Performance Benchmarks (macOS - Apple Silicon)
     runs-on: macos-15
-    timeout-minutes: 45
+    timeout-minutes: 75
 
     steps:
       - name: Checkout code
@@ -102,7 +102,7 @@ jobs:
   regression-detection:
     name: Performance Regression Detection
     runs-on: macos-15
-    timeout-minutes: 30
+    timeout-minutes: 75
     needs: [ benchmark-macos ]
     if: github.event_name == 'pull_request'
 
diff --git a/.github/workflows/swift-build-test.yml b/.github/workflows/swift-build-test.yml
index 1c2dee0b..83021f0f 100644
--- a/.github/workflows/swift-build-test.yml
+++ b/.github/workflows/swift-build-test.yml
@@ -19,7 +19,7 @@ jobs:
   test-macos:
     name: Test on macOS
     runs-on: macos-15
-    timeout-minutes: 30
+    timeout-minutes: 75
 
     steps:
       - name: Checkout code
@@ -48,7 +48,7 @@ jobs:
             --skip LargeBlock \
             --skip EndToEnd \
             --skip ClientServer
-        timeout-minutes: 20
+        timeout-minutes: 60
 
       - name: Build release
         run: swift build -c release -v