diff --git a/Project.toml b/Project.toml
index 57b1baf2..8e55e4de 100644
--- a/Project.toml
+++ b/Project.toml
@@ -5,14 +5,12 @@ version = "0.5.0"
 
 [deps]
 Dualization = "191a621a-6537-11e9-281d-650236a99e60"
-IntervalArithmetic = "d1acc4aa-44c8-5952-acd4-ba5d80a2a253"
 JuMP = "4076af6c-e467-56ae-b986-b466b2749572"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 MathOptInterface = "b8f27783-ece8-5eb3-8dc8-9495eed66fee"
 
 [compat]
 Dualization = "0.5.4"
-IntervalArithmetic = "< 0.18.0"
 JuMP = "1.0"
 MathOptInterface = "1.0"
 julia = "1.6"
diff --git a/src/BilevelJuMP.jl b/src/BilevelJuMP.jl
index 8381e418..85840b54 100644
--- a/src/BilevelJuMP.jl
+++ b/src/BilevelJuMP.jl
@@ -6,7 +6,6 @@ const MOIU = MathOptInterface.Utilities
 using JuMP
 using Dualization
 using LinearAlgebra
-using IntervalArithmetic
 
 export
 BilevelModel,
@@ -15,6 +14,7 @@ DualOf, BilevelAffExpr, BilevelQuadExpr
 
 @enum Level LOWER_BOTH UPPER_BOTH LOWER_ONLY UPPER_ONLY DUAL_OF_LOWER
 
+include("intervals.jl")
 include("moi.jl")
 include("moi_utilities.jl")
 
diff --git a/src/intervals.jl b/src/intervals.jl
new file mode 100644
index 00000000..f8531d54
--- /dev/null
+++ b/src/intervals.jl
@@ -0,0 +1,74 @@
+# Function in this file are heavily inspired in IntervalArithmetic.jl,
+# which is licensed under the MIT "Expat" License:
+#
+# Copyright (c) 2014-2021: David P. Sanders & Luis Benet
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+import Base.:+, Base.:-, Base.:*
+
+struct Interval{T}
+    lo::T
+    hi::T
+end
+function Interval(lo::T, hi::T) where {T <: Real}
+    # if hi < lo <= hi + eps(T)
+    #     lo = hi
+    # end
+    @assert lo <= hi
+    Interval{T}(lo, hi)
+end
+
+function Base.iszero(a::Interval)
+    iszero(a.hi) && iszero(a.lo)
+end
+
++(a::Interval) = a
+-(a::Interval) = Interval(-a.hi, -a.lo)
+
+function +(a::Interval{T}, b::T) where {T<:Real}
+    Interval(a.lo + b, a.hi + b)
+end
++(b::T, a::Interval{T}) where {T<:Real} = a+b
+
+function -(a::Interval{T}, b::T) where {T<:Real}
+    Interval(a.lo - b, a.hi - b)
+end
+function -(b::T, a::Interval{T}) where {T<:Real}
+    Interval(b - a.hi, b - a.lo)
+end
+
+function +(a::Interval{T}, b::Interval{T}) where T<:Real
+    Interval(a.lo + b.lo, a.hi + b.hi)
+end
+
+function -(a::Interval{T}, b::Interval{T}) where T<:Real
+    Interval(a.lo - b.hi, a.hi - b.lo)
+end
+
+## Multiplication
+function *(x::T, a::Interval{T}) where {T<:Real}
+    (iszero(a) || iszero(x)) && return Interval(zero(T), zero(T))
+    if x ≥ 0.0
+        return Interval(a.lo*x, a.hi*x)
+    else
+        return Interval(a.hi*x, a.lo*x)
+    end
+end
+
+*(a::Interval{T}, x::T) where {T<:Real} = x*a
diff --git a/src/moi.jl b/src/moi.jl
index c95465de..0d98832f 100644
--- a/src/moi.jl
+++ b/src/moi.jl
@@ -907,18 +907,18 @@ function get_bounds(var, map, fallback_bound = Inf)
         # TODO deal with precision and performance
         lower = ifelse(info.lower != -Inf, info.lower, -fallback_bound)
         upper = ifelse(info.upper != +Inf, info.upper, +fallback_bound)
-        return IntervalArithmetic.interval(lower, upper)
+        return Interval(lower, upper)
     elseif 0.0 <= fallback_bound <= Inf
-        return IntervalArithmetic.interval(-fallback_bound, fallback_bound)
+        return Interval(-fallback_bound, fallback_bound)
     else
         error("variable $var has no finite bounds defined")
     end
 end
 
-function set_bound(inter::IntervalArithmetic.Interval, ::LT{T}) where T
+function set_bound(inter::Interval, ::LT{T}) where T
     return inter.hi
 end
-function set_bound(inter::IntervalArithmetic.Interval, ::GT{T}) where T
+function set_bound(inter::Interval, ::GT{T}) where T
     return inter.lo
 end