diff --git a/source/lib/code_annotation.h b/source/lib/code_annotation.h
index 24b312fa31..5e55570375 100644
--- a/source/lib/code_annotation.h
+++ b/source/lib/code_annotation.h
@@ -27,8 +27,9 @@
 #ifndef INCLUDED_CODE_ANNOTATION
 #define INCLUDED_CODE_ANNOTATION
 
-#include "lib/sysdep/compiler.h"
+#include "lib/code_generation.h"
 #include "lib/sysdep/arch.h"	// ARCH_AMD64
+#include "lib/sysdep/compiler.h"
 
 #include <cstddef>
 
diff --git a/source/maths/BoundingBoxAligned.cpp b/source/maths/BoundingBoxAligned.cpp
index 32bd8cec60..2c1e6c0371 100644
--- a/source/maths/BoundingBoxAligned.cpp
+++ b/source/maths/BoundingBoxAligned.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -23,12 +23,15 @@
 
 #include "BoundingBoxAligned.h"
 
+#include "lib/debug.h"
 #include "maths/BoundingBoxOriented.h"
 #include "maths/Brush.h"
 #include "maths/Frustum.h"
 #include "maths/Matrix3D.h"
+#include "maths/Plane.h"
 
 #include <limits>
+#include <utility>
 
 const CBoundingBoxAligned CBoundingBoxAligned::EMPTY = CBoundingBoxAligned(); // initializes to an empty bound
 
diff --git a/source/maths/BoundingBoxAligned.h b/source/maths/BoundingBoxAligned.h
index be01f6311d..861bd74475 100644
--- a/source/maths/BoundingBoxAligned.h
+++ b/source/maths/BoundingBoxAligned.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -23,11 +23,12 @@
 #define INCLUDED_BOUND
 
 #include "maths/Vector3D.h"
-#include "graphics/ShaderProgramPtr.h"
 
+#include <algorithm>
+
+class CBoundingBoxOriented;
 class CFrustum;
 class CMatrix3D;
-class CBoundingBoxOriented;
 
 // Basic axis aligned bounding box (AABB) class
 class CBoundingBoxAligned
diff --git a/source/maths/BoundingBoxOriented.cpp b/source/maths/BoundingBoxOriented.cpp
index 4332362ef1..75e7c5e74f 100644
--- a/source/maths/BoundingBoxOriented.cpp
+++ b/source/maths/BoundingBoxOriented.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2019 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -20,7 +20,8 @@
 #include "BoundingBoxOriented.h"
 #include "maths/BoundingBoxAligned.h"
 
-#include <float.h>
+#include <cfloat>
+#include <cmath>
 
 const CBoundingBoxOriented CBoundingBoxOriented::EMPTY = CBoundingBoxOriented();
 
diff --git a/source/maths/BoundingSphere.cpp b/source/maths/BoundingSphere.cpp
index c6bff5674f..a48fc70dd0 100644
--- a/source/maths/BoundingSphere.cpp
+++ b/source/maths/BoundingSphere.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2019 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -20,6 +20,9 @@
 #include "maths/BoundingBoxAligned.h"
 #include "maths/BoundingSphere.h"
 
+#include <algorithm>
+#include <cmath>
+
 CBoundingSphere CBoundingSphere::FromSweptBox(const CBoundingBoxAligned& bbox)
 {
 	float maxX = std::max(fabsf(bbox[0].X), fabsf(bbox[1].X));
diff --git a/source/maths/Brush.cpp b/source/maths/Brush.cpp
index 667e48191a..f233b987e8 100644
--- a/source/maths/Brush.cpp
+++ b/source/maths/Brush.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -19,8 +19,10 @@
 
 #include "Brush.h"
 
+#include "lib/debug.h"
 #include "maths/BoundingBoxAligned.h"
 #include "maths/Frustum.h"
+#include "maths/Plane.h"
 
 CBrush::CBrush() = default;
 
diff --git a/source/maths/Brush.h b/source/maths/Brush.h
index cbc9afe103..90e439d53b 100644
--- a/source/maths/Brush.h
+++ b/source/maths/Brush.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -24,6 +24,7 @@
 
 #include "maths/Vector3D.h"
 
+#include <cstddef>
 #include <vector>
 
 class CBoundingBoxAligned;
diff --git a/source/maths/Fixed.cpp b/source/maths/Fixed.cpp
index e9e3c8cec8..eafbc77170 100644
--- a/source/maths/Fixed.cpp
+++ b/source/maths/Fixed.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2010 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -22,6 +22,7 @@
 #include "ps/CStr.h"
 
 #include <sstream>
+#include <string>
 
 template<>
 CFixed_15_16 CFixed_15_16::FromString(const CStr8& s)
diff --git a/source/maths/Fixed.h b/source/maths/Fixed.h
index 9364920285..81de7f6c24 100644
--- a/source/maths/Fixed.h
+++ b/source/maths/Fixed.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -18,9 +18,17 @@
 #ifndef INCLUDED_FIXED
 #define INCLUDED_FIXED
 
+#include "lib/debug.h"
+#include "lib/sysdep/compiler.h"
 #include "lib/types.h"
 #include "maths/Sqrt.h"
-#include "ps/CStrForward.h"
+
+#include <algorithm>
+#include <cmath>
+#include <limits>
+
+class CStr8;
+class CStrW;
 
 #ifndef NDEBUG
 #define USE_FIXED_OVERFLOW_CHECKS
@@ -312,7 +320,7 @@ public:
 		return CFixed(t);
 	}
 
-	constexpr CFixed Absolute() const { return CFixed(abs(value)); }
+	constexpr CFixed Absolute() const { return CFixed(std::abs(value)); }
 
 	/**
 	 * Multiply by a CFixed. Likely to overflow if both numbers are large,
diff --git a/source/maths/FixedVector2D.h b/source/maths/FixedVector2D.h
index 100c42597e..5906c8a61f 100644
--- a/source/maths/FixedVector2D.h
+++ b/source/maths/FixedVector2D.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2020 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -18,6 +18,7 @@
 #ifndef INCLUDED_FIXED_VECTOR2D
 #define INCLUDED_FIXED_VECTOR2D
 
+#include "lib/types.h"
 #include "maths/Fixed.h"
 #include "maths/Sqrt.h"
 
diff --git a/source/maths/FixedVector3D.h b/source/maths/FixedVector3D.h
index ad47c60b38..e4fbc9ed6a 100644
--- a/source/maths/FixedVector3D.h
+++ b/source/maths/FixedVector3D.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2020 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -18,6 +18,7 @@
 #ifndef INCLUDED_FIXED_VECTOR3D
 #define INCLUDED_FIXED_VECTOR3D
 
+#include "lib/types.h"
 #include "maths/Fixed.h"
 #include "maths/Sqrt.h"
 
diff --git a/source/maths/Frustum.cpp b/source/maths/Frustum.cpp
index b104b821d3..62f60d9d30 100644
--- a/source/maths/Frustum.cpp
+++ b/source/maths/Frustum.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -25,8 +25,8 @@ portal rendering, where a portal may have 3 or more edges.
 
 #include "Frustum.h"
 
+#include "lib/debug.h"
 #include "maths/BoundingBoxAligned.h"
-#include "maths/MathUtil.h"
 #include "maths/Matrix3D.h"
 
 CFrustum::CFrustum()
diff --git a/source/maths/Frustum.h b/source/maths/Frustum.h
index 66152c3bff..4f2ce6c78d 100644
--- a/source/maths/Frustum.h
+++ b/source/maths/Frustum.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -28,8 +28,11 @@ portal rendering, where a portal may have 3 or more edges.
 #ifndef INCLUDED_FRUSTUM
 #define INCLUDED_FRUSTUM
 
+#include "maths/Vector3D.h"
 #include "maths/Plane.h"
 
+#include <cstddef>
+
 class CBoundingBoxAligned;
 class CMatrix3D;
 
diff --git a/source/maths/MD5.h b/source/maths/MD5.h
index f1c0039faa..fc84607e5e 100644
--- a/source/maths/MD5.h
+++ b/source/maths/MD5.h
@@ -18,6 +18,9 @@
 #ifndef INCLUDED_MD5
 #define INCLUDED_MD5
 
+#include "lib/code_annotation.h"
+#include "lib/types.h"
+
 #include <cstring>
 
 /**
diff --git a/source/maths/Matrix3D.cpp b/source/maths/Matrix3D.cpp
index 4d26f05ff8..5a17b96078 100644
--- a/source/maths/Matrix3D.cpp
+++ b/source/maths/Matrix3D.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2019 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -23,8 +23,10 @@
 #include "precompiled.h"
 
 #include "Matrix3D.h"
-#include "Quaternion.h"
-#include "Vector4D.h"
+
+#include "maths/Quaternion.h"
+
+#include <cmath>
 
 //Sets the identity matrix
 void CMatrix3D::SetIdentity ()
diff --git a/source/maths/Matrix3D.h b/source/maths/Matrix3D.h
index 8e8523c141..e2db5947d7 100644
--- a/source/maths/Matrix3D.h
+++ b/source/maths/Matrix3D.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -27,6 +27,8 @@
 #include "maths/Vector4D.h"
 #include "ps/containers/Span.h"
 
+#include <cstddef>
+
 class CQuaternion;
 
 // CMatrix3D: a 4x4 matrix class for common operations in 3D
diff --git a/source/maths/NUSpline.cpp b/source/maths/NUSpline.cpp
index a30f8ed222..4b7d04a535 100644
--- a/source/maths/NUSpline.cpp
+++ b/source/maths/NUSpline.cpp
@@ -17,10 +17,15 @@
 
 #include "precompiled.h"
 
-#include <algorithm>
-
 #include "NUSpline.h"
-#include "Matrix3D.h"
+
+#include "lib/debug.h"
+#include "maths/FixedVector3D.h"
+#include "maths/Matrix3D.h"
+#include "maths/Vector3D.h"
+
+#include <utility>
+
 
 //Note: column major order!  Each set of 4 constitutes a column.
 CMatrix3D HermiteSpline(2.f, -3.f, 0.f, 1.f,
diff --git a/source/maths/NUSpline.h b/source/maths/NUSpline.h
index 4e324c2b58..7fe7149f66 100644
--- a/source/maths/NUSpline.h
+++ b/source/maths/NUSpline.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2020 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -26,8 +26,9 @@
 
 #define MAX_SPLINE_NODES 128
 
-#include "FixedVector3D.h"
-#include "Vector3D.h"
+#include "maths/Fixed.h"
+#include "maths/FixedVector3D.h"
+#include "maths/Vector3D.h"
 
 #include <vector>
 
diff --git a/source/maths/Plane.cpp b/source/maths/Plane.cpp
index 04f0fe9a9b..267c1b9d52 100644
--- a/source/maths/Plane.cpp
+++ b/source/maths/Plane.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -25,7 +25,9 @@
 #include "precompiled.h"
 
 #include "Plane.h"
-#include "MathUtil.h"
+
+#include "maths/MathUtil.h"
+#include "maths/Vector3D.h"
 
 const float CPlane::m_EPS = 0.001f;
 
diff --git a/source/maths/Quaternion.cpp b/source/maths/Quaternion.cpp
index 1aac49b6fa..4d0a040523 100644
--- a/source/maths/Quaternion.cpp
+++ b/source/maths/Quaternion.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -19,8 +19,11 @@
 
 #include "Quaternion.h"
 
-#include "MathUtil.h"
-#include "Matrix3D.h"
+#include "maths/MathUtil.h"
+#include "maths/Matrix3D.h"
+#include "maths/Vector3D.h"
+
+#include <cmath>
 
 const float EPSILON=0.0001f;
 
diff --git a/source/maths/Rect.cpp b/source/maths/Rect.cpp
index ca23057255..b430e7a041 100644
--- a/source/maths/Rect.cpp
+++ b/source/maths/Rect.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2024 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -22,6 +22,8 @@
 #include "maths/Size2D.h"
 #include "maths/Vector2D.h"
 
+#include <algorithm>
+
 CRect::CRect() :
 	left(0.f), top(0.f), right(0.f), bottom(0.f)
 {
diff --git a/source/maths/Sqrt.h b/source/maths/Sqrt.h
index 8db047123c..6685e08626 100644
--- a/source/maths/Sqrt.h
+++ b/source/maths/Sqrt.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2010 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -18,6 +18,8 @@
 #ifndef INCLUDED_MATH_SQRT
 #define INCLUDED_MATH_SQRT
 
+#include "lib/types.h"
+
 /**
  * 64-bit integer square root.
  * Returns r such that r^2 <= n < (r+1)^2, for the complete u64 range.
diff --git a/source/maths/Vector2D.h b/source/maths/Vector2D.h
index 1e9db33f65..dd118b4a19 100644
--- a/source/maths/Vector2D.h
+++ b/source/maths/Vector2D.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -20,7 +20,8 @@
 
 #include "ps/containers/Span.h"
 
-#include <math.h>
+#include <cmath>
+#include <cstddef>
 
 class CSize2D;
 
diff --git a/source/maths/Vector3D.h b/source/maths/Vector3D.h
index d5a75df090..0b8440cda0 100644
--- a/source/maths/Vector3D.h
+++ b/source/maths/Vector3D.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -25,6 +25,8 @@
 
 #include "ps/containers/Span.h"
 
+#include <cstddef>
+
 class CFixedVector3D;
 
 class CVector3D
diff --git a/source/maths/Vector4D.h b/source/maths/Vector4D.h
index 3a5686e74a..ec8189b041 100644
--- a/source/maths/Vector4D.h
+++ b/source/maths/Vector4D.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -25,7 +25,7 @@
 
 #include "ps/containers/Span.h"
 
-#include <math.h>
+#include <cstddef>
 
 class CVector4D
 {
diff --git a/source/maths/tests/test_Bound.h b/source/maths/tests/test_Bound.h
index ac562a3aa9..14c4c02d05 100644
--- a/source/maths/tests/test_Bound.h
+++ b/source/maths/tests/test_Bound.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2019 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,10 +17,12 @@
 
 #include "lib/self_test.h"
 
-#include "lib/posix/posix.h"
 #include "maths/BoundingBoxAligned.h"
 #include "maths/BoundingBoxOriented.h"
 #include "maths/Matrix3D.h"
+#include "maths/Vector3D.h"
+
+#include <cmath>
 
 #define TS_ASSERT_VEC_DELTA(v, x, y, z, delta) \
 	TS_ASSERT_DELTA(v.X, x, delta); \
diff --git a/source/maths/tests/test_BoundingSphere.h b/source/maths/tests/test_BoundingSphere.h
index 58bc0c5274..3663215798 100644
--- a/source/maths/tests/test_BoundingSphere.h
+++ b/source/maths/tests/test_BoundingSphere.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2019 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -19,8 +19,10 @@
 
 #include "maths/BoundingBoxAligned.h"
 #include "maths/BoundingSphere.h"
+#include "maths/Vector3D.h"
 
 #include <cmath>
+#include <cstddef>
 
 class TestBoundingSphere : public CxxTest::TestSuite
 {
diff --git a/source/maths/tests/test_Brush.h b/source/maths/tests/test_Brush.h
index 4b13f371b0..7a0b8c0231 100644
--- a/source/maths/tests/test_Brush.h
+++ b/source/maths/tests/test_Brush.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2021 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,9 +17,18 @@
 
 #include "lib/self_test.h"
 
-#include "maths/Brush.h"
 #include "maths/BoundingBoxAligned.h"
-#include "maths/Frustum.h"
+#include "maths/Brush.h"
+#include "maths/Plane.h"
+#include "maths/Vector3D.h"
+#include "maths/Vector4D.h"
+
+#include <algorithm>
+#include <cmath>
+#include <cstdarg>
+#include <cstddef>
+#include <iterator>
+#include <vector>
 
 class TestBrush : public CxxTest::TestSuite
 {
diff --git a/source/maths/tests/test_Fixed.h b/source/maths/tests/test_Fixed.h
index 32895ef2fe..d48e0bed47 100644
--- a/source/maths/tests/test_Fixed.h
+++ b/source/maths/tests/test_Fixed.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2022 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -22,8 +22,14 @@
 # pragma warning(push, 1)
 # pragma warning(disable: 4724)
 #endif
+
+#include "lib/types.h"
 #include "maths/Fixed.h"
-#include "maths/MathUtil.h"
+#include "ps/CStr.h"
+
+#include <algorithm>
+#include <cmath>
+#include <limits>
 
 class TestFixed : public CxxTest::TestSuite
 {
diff --git a/source/maths/tests/test_FixedVector2D.h b/source/maths/tests/test_FixedVector2D.h
index d1e0b3c721..f90b38f992 100644
--- a/source/maths/tests/test_FixedVector2D.h
+++ b/source/maths/tests/test_FixedVector2D.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2020 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,8 +17,12 @@
 
 #include "lib/self_test.h"
 
+#include "lib/types.h"
+#include "maths/Fixed.h"
 #include "maths/FixedVector2D.h"
 
+#include <cmath>
+
 #define TS_ASSERT_VEC_EQUALS(v, x, y) \
 	TS_ASSERT_EQUALS(v.X.ToDouble(), x); \
 	TS_ASSERT_EQUALS(v.Y.ToDouble(), y);
diff --git a/source/maths/tests/test_FixedVector3D.h b/source/maths/tests/test_FixedVector3D.h
index e4cb0b259b..d2515f0d09 100644
--- a/source/maths/tests/test_FixedVector3D.h
+++ b/source/maths/tests/test_FixedVector3D.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2010 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,8 +17,12 @@
 
 #include "lib/self_test.h"
 
+#include "lib/types.h"
+#include "maths/Fixed.h"
 #include "maths/FixedVector3D.h"
 
+#include <cmath>
+
 #define TS_ASSERT_VEC_EQUALS(v, x, y, z) \
 	TS_ASSERT_EQUALS(v.X.ToDouble(), x); \
 	TS_ASSERT_EQUALS(v.Y.ToDouble(), y); \
diff --git a/source/maths/tests/test_MD5.h b/source/maths/tests/test_MD5.h
index 7bce6ed0ad..ae36c3f0ed 100644
--- a/source/maths/tests/test_MD5.h
+++ b/source/maths/tests/test_MD5.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2018 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,9 +17,13 @@
 
 #include "lib/self_test.h"
 
+#include "lib/types.h"
 #include "maths/MD5.h"
 #include "ps/Util.h"
 
+#include <cstring>
+#include <string>
+
 class TestMD5 : public CxxTest::TestSuite
 {
 public:
diff --git a/source/maths/tests/test_Matrix3d.h b/source/maths/tests/test_Matrix3d.h
index 5a4c68d1ac..b4b8020bbe 100644
--- a/source/maths/tests/test_Matrix3d.h
+++ b/source/maths/tests/test_Matrix3d.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2024 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,11 +17,12 @@
 
 #include "lib/self_test.h"
 
+#include "lib/lib.h"
 #include "maths/Matrix3D.h"
 #include "maths/Quaternion.h"
+#include "maths/Vector3D.h"
 
 #include <cmath>
-#include <cstdlib>
 #include <random>
 
 class TestMatrix : public CxxTest::TestSuite
diff --git a/source/maths/tests/test_Sqrt.h b/source/maths/tests/test_Sqrt.h
index 702244b9cd..542cc38e5f 100644
--- a/source/maths/tests/test_Sqrt.h
+++ b/source/maths/tests/test_Sqrt.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2019 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -17,11 +17,14 @@
 
 #include "lib/self_test.h"
 
+#include "lib/types.h"
 #include "maths/Sqrt.h"
 
 #include <boost/random/mersenne_twister.hpp>
 #include <boost/random/uniform_int_distribution.hpp>
 #include <boost/random/variate_generator.hpp>
+#include <cmath>
+#include <cstddef>
 
 class TestSqrt : public CxxTest::TestSuite
 {