diff --git a/Project.toml b/Project.toml
index 3618f7c..1a2f328 100644
--- a/Project.toml
+++ b/Project.toml
@@ -7,18 +7,22 @@ LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 LinearOperators = "5c8ed15e-5a4c-59e4-a42b-c7e8811fb125"
 NLPModels = "a4795742-8479-5a88-8948-cc11e1c8c1a6"
 NLPModelsModifiers = "e01155f1-5c6f-4375-a9d8-616dd036575f"
-Requires = "ae029012-a4dd-5104-9daa-d747884805df"
 SolverCore = "ff4d7338-4cf1-434d-91df-b86cb86fb843"
 SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 SparseMatricesCOO = "fa32481b-f100-4b48-8dc8-c62f61b13870"
 
+[weakdeps]
+QPSReader = "10f199a5-22af-520b-b891-7ce84a7b1bd0"
+
+[extensions]
+QuadraticModelsQPSReaderExt = "QPSReader"
+
 [compat]
-LinearAlgebra = "1.6"
-LinearOperators = "2.2.2, 2.3"
-NLPModels = "0.18, 0.19, 0.20, 0.21"
-NLPModelsModifiers = "0.6, 0.7"
-Requires = "0.3, 0.4, 0.5, 1.0"
+LinearAlgebra = "1.10"
+LinearOperators = "2.3"
+NLPModels = "0.21.4"
+NLPModelsModifiers = "0.7"
 SolverCore = "0.3"
-SparseArrays = "1.6"
-SparseMatricesCOO = "0.1.1, 0.2"
-julia = "1.6"
+SparseArrays = "1.10"
+SparseMatricesCOO = "0.2.3"
+julia = "1.10"
diff --git a/README.md b/README.md
index 8f91003..9899d2a 100644
--- a/README.md
+++ b/README.md
@@ -13,7 +13,7 @@ The problems represented have the form
 <p align="center">
 optimize &nbsp; c₀ + cᵀ x + ½ xᵀ Q x
 &nbsp;&nbsp;
-subject to &nbsp; L ≤ Ax ≤ U and ℓ ≤ x ≤ u,
+subject to &nbsp; L ≤ Ax ≤ U and ℓ ≤ x ≤ u,
 </p>
 
 where the square symmetric matrix Q is zero for linear optimization problems.
diff --git a/src/qps.jl b/ext/QuadraticModelsQPSReaderExt.jl
similarity index 55%
rename from src/qps.jl
rename to ext/QuadraticModelsQPSReaderExt.jl
index e80a1e7..c1a721b 100644
--- a/src/qps.jl
+++ b/ext/QuadraticModelsQPSReaderExt.jl
@@ -1,7 +1,10 @@
-using .QPSReader
+module QuadraticModelsQPSReaderExt
 
-function QuadraticModel(qps::QPSData, x0 = zeros(qps.nvar))
-  QuadraticModel(
+import QuadraticModels
+import QPSReader
+
+function QuadraticModels.QuadraticModel(qps::QPSReader.QPSData, x0 = zeros(qps.nvar))
+  QuadraticModels.QuadraticModel(
     qps.c,
     qps.qrows,
     qps.qcols,
@@ -17,3 +20,5 @@ function QuadraticModel(qps::QPSData, x0 = zeros(qps.nvar))
     x0 = x0,
   )
 end
+
+end
diff --git a/src/QuadraticModels.jl b/src/QuadraticModels.jl
index f0a7c1b..4dfca2c 100644
--- a/src/QuadraticModels.jl
+++ b/src/QuadraticModels.jl
@@ -6,9 +6,6 @@ using LinearAlgebra, SparseArrays
 # our packages
 using LinearOperators, NLPModels, NLPModelsModifiers, SolverCore, SparseMatricesCOO
 
-# auxiliary packages
-using Requires
-
 import NLPModels:
   objgrad,
   objgrad!,
@@ -36,8 +33,4 @@ include("linalg_utils.jl")
 include("qpmodel.jl")
 include("presolve/presolve.jl")
 
-function __init__()
-  @require QPSReader = "10f199a5-22af-520b-b891-7ce84a7b1bd0" include("qps.jl")
-end
-
 end # module
diff --git a/test/Project.toml b/test/Project.toml
index 18d638f..d1aea91 100644
--- a/test/Project.toml
+++ b/test/Project.toml
@@ -16,7 +16,7 @@ Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 [compat]
 ADNLPModels = "0.8"
 LinearOperators = "2"
-NLPModels = "0.21"
+NLPModels = "0.21.4"
 NLPModelsModifiers = "0.7"
 NLPModelsTest = "0.10"
 QPSReader = "0.2"