diff --git a/src/maths.go b/src/maths.go
new file mode 100644
index 0000000..e375c79
--- /dev/null
+++ b/src/maths.go
@@ -0,0 +1,64 @@
+package main
+
+import (
+	"github.com/wadey/go-rounding"
+)
+
+var maths = ArMap{
+	"round": builtinFunc{"round", func(a ...any) (any, ArErr) {
+		if len(a) == 0 {
+			return nil, ArErr{TYPE: "round", message: "round takes 1 argument",
+				EXISTS: true}
+		}
+		precision := newNumber()
+		if len(a) > 1 {
+			switch x := a[1].(type) {
+			case number:
+				if !x.IsInt() {
+					return nil, ArErr{TYPE: "TypeError", message: "Cannot round to '" + typeof(a[1]) + "'", EXISTS: true}
+				}
+				precision = x
+			default:
+				return nil, ArErr{TYPE: "TypeError", message: "Cannot round to '" + typeof(a[1]) + "'", EXISTS: true}
+			}
+		}
+
+		switch x := a[0].(type) {
+		case number:
+			return rounding.Round(newNumber().Set(x), int(precision.Num().Int64()), rounding.HalfUp), ArErr{}
+		}
+		return nil, ArErr{TYPE: "TypeError", message: "Cannot round '" + typeof(a[0]) + "'", EXISTS: true}
+	}},
+	"floor": builtinFunc{"floor", func(a ...any) (any, ArErr) {
+		if len(a) == 0 {
+			return nil, ArErr{TYPE: "floor", message: "floor takes 1 argument",
+				EXISTS: true}
+		}
+		switch x := a[0].(type) {
+		case number:
+			n := newNumber().Set(x)
+			if n.Sign() < 0 {
+				return rounding.Round(n, 0, rounding.Up), ArErr{}
+			}
+			return rounding.Round(n, 0, rounding.Down), ArErr{}
+		}
+		return nil, ArErr{TYPE: "TypeError", message: "Cannot floor '" + typeof(a[0]) + "'", EXISTS: true}
+	}},
+	"ceil": builtinFunc{"ceil", func(a ...any) (any, ArErr) {
+		if len(a) == 0 {
+			return nil, ArErr{TYPE: "ceil", message: "ceil takes 1 argument",
+				EXISTS: true}
+		}
+
+		switch x := a[0].(type) {
+		case number:
+			n := newNumber().Set(x)
+			if n.Sign() < 0 {
+				return rounding.Round(n, 0, rounding.Down), ArErr{}
+			}
+			return rounding.Round(n, 0, rounding.Up), ArErr{}
+		}
+		return nil, ArErr{TYPE: "TypeError", message: "Cannot ceil '" + typeof(a[0]) + "'", EXISTS: true}
+	}},
+	"sqrt": builtinFunc{"sqrt", ArgonSqrt},
+}