diff --git a/Project.toml b/Project.toml
index 1fcfffa..3deeafb 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "OptimizationBase"
 uuid = "bca83a33-5cc9-4baa-983d-23429ab6bcbb"
 authors = ["Vaibhav Dixit <vaibhavyashdixit@gmail.com> and contributors"]
-version = "2.0.4"
+version = "2.1.0"
 
 [deps]
 ADTypes = "47edcb42-4c32-4615-8424-f2b9edc5f35b"
diff --git a/ext/OptimizationZygoteExt.jl b/ext/OptimizationZygoteExt.jl
index f31be4b..d0ec969 100644
--- a/ext/OptimizationZygoteExt.jl
+++ b/ext/OptimizationZygoteExt.jl
@@ -290,13 +290,13 @@ function OptimizationBase.instantiate_function(
     adtype, soadtype = OptimizationBase.generate_sparse_adtype(adtype)
 
     if g == true && f.grad === nothing
-        extras_grad = prepare_gradient(_f, adtype.dense_ad, x, Constant(p))
+        extras_grad = prepare_gradient(f.f, adtype.dense_ad, x, Constant(p))
         function grad(res, θ)
-            gradient!(_f, res, extras_grad, adtype.dense_ad, θ, Constant(p))
+            gradient!(f.f, res, extras_grad, adtype.dense_ad, θ, Constant(p))
         end
         if p !== SciMLBase.NullParameters() && p !== nothing
             function grad(res, θ, p)
-                gradient!(_f, res, extras_grad, adtype.dense_ad, θ, Constant(p))
+                gradient!(f.f, res, extras_grad, adtype.dense_ad, θ, Constant(p))
             end
         end
     elseif g == true
@@ -307,17 +307,17 @@ function OptimizationBase.instantiate_function(
 
     if fg == true && f.fg === nothing
         if g == false
-            extras_grad = prepare_gradient(_f, adtype.dense_ad, x, Constant(p))
+            extras_grad = prepare_gradient(f.f, adtype.dense_ad, x, Constant(p))
         end
         function fg!(res, θ)
             (y, _) = value_and_gradient!(
-                _f, res, extras_grad, adtype.dense_ad, θ, Constant(p))
+                f.f, res, extras_grad, adtype.dense_ad, θ, Constant(p))
             return y
         end
         if p !== SciMLBase.NullParameters() && p !== nothing
             function fg!(res, θ, p)
                 (y, _) = value_and_gradient!(
-                    _f, res, extras_grad, adtype.dense_ad, θ, Constant(p))
+                    f.f, res, extras_grad, adtype.dense_ad, θ, Constant(p))
                 return y
             end
         end
@@ -330,16 +330,16 @@ function OptimizationBase.instantiate_function(
     hess_sparsity = f.hess_prototype
     hess_colors = f.hess_colorvec
     if h == true && f.hess === nothing
-        prep_hess = prepare_hessian(_f, soadtype, x, Constant(p))
+        prep_hess = prepare_hessian(f.f, soadtype, x, Constant(p))
         function hess(res, θ)
-            hessian!(_f, res, prep_hess, soadtype, θ, Constant(p))
+            hessian!(f.f, res, prep_hess, soadtype, θ, Constant(p))
         end
-        hess_sparsity = extras_hess.coloring_result.S
-        hess_colors = extras_hess.coloring_result.color
+        hess_sparsity = prep_hess.coloring_result.S
+        hess_colors = prep_hess.coloring_result.color
 
         if p !== SciMLBase.NullParameters() && p !== nothing
             function hess(res, θ, p)
-                hessian!(_f, res, prep_hess, soadtype, θ, Constant(p))
+                hessian!(f.f, res, prep_hess, soadtype, θ, Constant(p))
             end
         end
     elseif h == true
@@ -351,14 +351,14 @@ function OptimizationBase.instantiate_function(
     if fgh == true && f.fgh === nothing
         function fgh!(G, H, θ)
             (y, _, _) = value_derivative_and_second_derivative!(
-                _f, G, H, θ, prep_hess, soadtype, Constant(p))
+                f.f, G, H, θ, prep_hess, soadtype, Constant(p))
             return y
         end
 
         if p !== SciMLBase.NullParameters() && p !== nothing
             function fgh!(G, H, θ, p)
                 (y, _, _) = value_derivative_and_second_derivative!(
-                    _f, G, H, θ, prep_hess, soadtype, Constant(p))
+                    f.f, G, H, θ, prep_hess, soadtype, Constant(p))
                 return y
             end
         end
@@ -371,11 +371,11 @@ function OptimizationBase.instantiate_function(
     if hv == true && f.hv === nothing
         prep_hvp = prepare_hvp(_f, soadtype.dense_ad, x, zeros(eltype(x), size(x)))
         function hv!(H, θ, v)
-            hvp!(_f, H, prep_hvp, soadtype.dense_ad, θ, (v,), Constant(p))
+            hvp!(f.f, (H,), prep_hvp, soadtype.dense_ad, θ, (v,), Constant(p))
         end
         if p !== SciMLBase.NullParameters() && p !== nothing
             function hv!(H, θ, v, p)
-                hvp!(_f, H, prep_hvp, soadtype.dense_ad, θ, (v,), Constant(p))
+                hvp!(f.f, (H,), prep_hvp, soadtype.dense_ad, θ, (v,), Constant(p))
             end
         end
     elseif hv == true
@@ -411,15 +411,15 @@ function OptimizationBase.instantiate_function(
     cons_jac_prototype = f.cons_jac_prototype
     cons_jac_colorvec = f.cons_jac_colorvec
     if cons !== nothing && cons_j == true && f.cons_j === nothing
-        prep_jac = prepare_jacobian(cons_oop, adtype, x, Constant(p))
+        prep_jac = prepare_jacobian(cons_oop, adtype, x)
         function cons_j!(J, θ)
-            jacobian!(cons_oop, J, prep_jac, adtype, θ, Constant(p))
+            jacobian!(cons_oop, J, prep_jac, adtype, θ)
             if size(J, 1) == 1
                 J = vec(J)
             end
         end
-        cons_jac_prototype = extras_jac.coloring_result.S
-        cons_jac_colorvec = extras_jac.coloring_result.color
+        cons_jac_prototype = prep_jac.coloring_result.S
+        cons_jac_colorvec = prep_jac.coloring_result.color
     elseif cons !== nothing && cons_j == true
         cons_j! = (J, θ) -> f.cons_j(J, θ, p)
     else
@@ -428,10 +428,10 @@ function OptimizationBase.instantiate_function(
 
     if f.cons_vjp === nothing && cons_vjp == true && cons !== nothing
         extras_pullback = prepare_pullback(
-            cons_oop, adtype.dense_ad, x, (ones(eltype(x), num_cons),), Constant(p))
+            cons_oop, adtype.dense_ad, x, (ones(eltype(x), num_cons),))
         function cons_vjp!(J, θ, v)
             pullback!(
-                cons_oop, (J,), extras_pullback, adtype.dense_ad, θ, (v,), Constant(p))
+                cons_oop, (J,), extras_pullback, adtype.dense_ad, θ, (v,))
         end
     elseif cons_vjp == true
         cons_vjp! = (J, θ, v) -> f.cons_vjp(J, θ, v, p)
@@ -441,10 +441,10 @@ function OptimizationBase.instantiate_function(
 
     if f.cons_jvp === nothing && cons_jvp == true && cons !== nothing
         extras_pushforward = prepare_pushforward(
-            cons_oop, adtype.dense_ad, x, (ones(eltype(x), length(x)),), Constant(p))
+            cons_oop, adtype.dense_ad, x, (ones(eltype(x), length(x)),))
         function cons_jvp!(J, θ, v)
             pushforward!(
-                cons_oop, (J,), extras_pushforward, adtype.dense_ad, θ, (v,), Constant(p))
+                cons_oop, (J,), extras_pushforward, adtype.dense_ad, θ, (v,))
         end
     elseif cons_jvp == true
         cons_jvp! = (J, θ, v) -> f.cons_jvp(J, θ, v, p)
@@ -482,7 +482,7 @@ function OptimizationBase.instantiate_function(
 
         function lag_h!(H::AbstractMatrix, θ, σ, λ)
             if σ == zero(eltype(θ))
-                cons_h(H, θ)
+                cons_h!(H, θ)
                 H *= λ
             else
                 hessian!(lagrangian, H, lag_extras, soadtype, θ,
diff --git a/test/adtests.jl b/test/adtests.jl
index 2872cf1..7b11a09 100644
--- a/test/adtests.jl
+++ b/test/adtests.jl
@@ -739,7 +739,7 @@ end
 
     # Instantiate the optimization problem
     optprob = OptimizationBase.instantiate_function(optf, x0,
-        OptimizationBase.AutoSparseForwardDiff(),
+        OptimizationBase.AutoSparseZygote(),
         nothing, 2, g = true, h = true, cons_j = true, cons_h = true, lag_h = true)
     # Test gradient
     G = zeros(3)