diff --git a/docs/src/api.md b/docs/src/api.md
index cf767b9..29150c0 100644
--- a/docs/src/api.md
+++ b/docs/src/api.md
@@ -46,7 +46,7 @@ is_markovian
 
 If the index provider contains parameters that change during the course of the simulation
 at discrete time points, it must implement the following methods to ensure correct
-functioning of [`getu`](@ref) and [`getp`](@ref) for value providers that save the parameter
+functioning of [`getsym`](@ref) and [`getp`](@ref) for value providers that save the parameter
 timeseries. Note that there can be multiple parameter timeseries, in case different parameters
 may change at different times.
 
@@ -69,10 +69,13 @@ is_timeseries
 state_values
 set_state!
 current_time
-getu
-setu
+getsym
+setsym
 ```
 
+!!! note
+    `getu` and `setu` have been renamed to [`getsym`](@ref) and [`setsym`](@ref) respectively.
+
 #### Historical value providers
 
 ```@docs
@@ -95,7 +98,7 @@ ParameterIndexingProxy
 
 If a solution object saves a timeseries of parameter values that are updated during the
 simulation (such as by callbacks), it must implement the following methods to ensure
-correct functioning of [`getu`](@ref) and [`getp`](@ref).
+correct functioning of [`getsym`](@ref) and [`getp`](@ref).
 
 Parameter timeseries support requires that the value provider store the different
 timeseries in a [`ParameterTimeseriesCollection`](@ref).
diff --git a/docs/src/complete_sii.md b/docs/src/complete_sii.md
index ae55e98..c75cdc8 100644
--- a/docs/src/complete_sii.md
+++ b/docs/src/complete_sii.md
@@ -174,9 +174,9 @@ end
 ```
 
 If a type contains the value of state variables, it can define [`state_values`](@ref) to
-enable the usage of [`getu`](@ref) and [`setu`](@ref). These methods retturn getter/
+enable the usage of [`getsym`](@ref) and [`setsym`](@ref). These methods retturn getter/
 setter functions to access or update the value of a state variable (or a collection of
-them). If the type also supports generating [`observed`](@ref) functions, `getu` also
+them). If the type also supports generating [`observed`](@ref) functions, `getsym` also
 enables returning functions to access the value of arbitrary expressions involving
 the system's symbols. This also requires that the type implement
 [`parameter_values`](@ref) and [`current_time`](@ref) (if the system is time-dependent).
@@ -202,13 +202,13 @@ Then the following example would work:
 ```julia
 sys = ExampleSystem(Dict(:x => 1, :y => 2, :z => 3), Dict(:a => 1, :b => 2), :t, Dict())
 integrator = ExampleIntegrator([1.0, 2.0, 3.0], [4.0, 5.0], 6.0, sys)
-getx = getu(sys, :x)
+getx = getsym(sys, :x)
 getx(integrator) # 1.0
 
-get_expr = getu(sys, :(x + y + t))
+get_expr = getsym(sys, :(x + y + t))
 get_expr(integrator) # 13.0
 
-setx! = setu(sys, :y)
+setx! = setsym(sys, :y)
 setx!(integrator, 0.0)
 getx(integrator) # 0.0
 ```
@@ -216,7 +216,7 @@ getx(integrator) # 0.0
 In case a type stores timeseries data (such as solutions), then it must also implement
 the [`Timeseries`](@ref) trait. The type would then return a timeseries from
 [`state_values`](@ref) and [`current_time`](@ref) and the function returned from
-[`getu`](@ref) would then return a timeseries as well. For example, consider the
+[`getsym`](@ref) would then return a timeseries as well. For example, consider the
 `ExampleSolution` below:
 
 ```julia
@@ -242,20 +242,20 @@ Then the following example would work:
 ```julia
 # using the same system that the ExampleIntegrator used
 sol = ExampleSolution([[1.0, 2.0, 3.0], [1.5, 2.5, 3.5]], [4.0, 5.0], [6.0, 7.0], sys)
-getx = getu(sys, :x)
+getx = getsym(sys, :x)
 getx(sol) # [1.0, 1.5]
 
-get_expr = getu(sys, :(x + y + t))
+get_expr = getsym(sys, :(x + y + t))
 get_expr(sol) # [9.0, 11.0]
 
-get_arr = getu(sys, [:y, :(x + a)])
+get_arr = getsym(sys, [:y, :(x + a)])
 get_arr(sol) # [[2.0, 5.0], [2.5, 5.5]]
 
-get_tuple = getu(sys, (:z, :(z * t)))
+get_tuple = getsym(sys, (:z, :(z * t)))
 get_tuple(sol) # [(3.0, 18.0), (3.5, 24.5)]
 ```
 
-Note that `setu` is not designed to work for `Timeseries` objects.
+Note that `setsym` is not designed to work for `Timeseries` objects.
 
 If a type needs to perform some additional actions when updating the state/parameters
 or if it is not possible to return a mutable reference to the state/parameter vector
@@ -315,7 +315,7 @@ setp(integrator, :b)(integrator, 3.0) # functionally the same as above
 
 If a solution object includes modified parameter values (such as through callbacks) during the
 simulation, it must implement several additional functions for correct functioning of
-[`getu`](@ref) and [`getp`](@ref). [`ParameterTimeseriesCollection`](@ref) helps in
+[`getsym`](@ref) and [`getp`](@ref). [`ParameterTimeseriesCollection`](@ref) helps in
 implementing parameter timeseries objects. The following mockup gives an example of
 correct implementation of these functions and the indexing syntax they enable.
 
@@ -457,12 +457,12 @@ sol.ps[:(b + c)] # observed quantities work too
 ```
 
 ```@example param_timeseries
-getu(sol, :b)(sol) # works
+getsym(sol, :b)(sol) # works
 ```
 
 ```@example param_timeseries
 try
-  getu(sol, [:b, :d])(sol) # errors since :b and :d belong to different timeseries
+  getsym(sol, [:b, :d])(sol) # errors since :b and :d belong to different timeseries
 catch e
   showerror(stdout, e)
 end
diff --git a/docs/src/usage.md b/docs/src/usage.md
index 693256d..dfeac57 100644
--- a/docs/src/usage.md
+++ b/docs/src/usage.md
@@ -123,11 +123,11 @@ sol[allvariables] # equivalent to sol[all_variable_symbols(sol)]
 
 ### Evaluating expressions
 
-`getu` also generates functions for expressions if the object passed to it supports
+`getsym` also generates functions for expressions if the object passed to it supports
 [`observed`](@ref). For example:
 
 ```@example Usage
-getu(prob, x + y + z)(prob)
+getsym(prob, x + y + z)(prob)
 ```
 
 To evaluate this function using values other than the ones contained in `prob`, we need
@@ -137,7 +137,7 @@ which has trivial implementations of the above functions. We can thus do:
 
 ```@example Usage
 temp_state = ProblemState(; u = [0.1, 0.2, 0.3, 0.4], p = parameter_values(prob))
-getu(prob, x + y + z)(temp_state)
+getsym(prob, x + y + z)(temp_state)
 ```
 
 Note that providing all of the state vector, parameter object and time may not be
diff --git a/src/SymbolicIndexingInterface.jl b/src/SymbolicIndexingInterface.jl
index 7b2f3cc..f444fb4 100644
--- a/src/SymbolicIndexingInterface.jl
+++ b/src/SymbolicIndexingInterface.jl
@@ -35,7 +35,7 @@ include("parameter_timeseries_collection.jl")
 export getp, setp, setp_oop
 include("parameter_indexing.jl")
 
-export getu, setu
+export getsym, setsym, getu, setu
 include("state_indexing.jl")
 
 export BatchedInterface, setsym_oop, associated_systems
diff --git a/src/batched_interface.jl b/src/batched_interface.jl
index c8d02d8..ad8273c 100644
--- a/src/batched_interface.jl
+++ b/src/batched_interface.jl
@@ -2,7 +2,7 @@
     struct BatchedInterface{S <: AbstractVector, I}
     function BatchedInterface(indp_syms::Tuple...)
 
-A struct which stores information for batched calls to [`getu`](@ref) or [`setu`](@ref).
+A struct which stores information for batched calls to [`getsym`](@ref) or [`setsym`](@ref).
 Given `Tuple`s, where the first element of each tuple is an index provider and the second
 an array of symbolic variables (either states or parameters) in the index provider,
 `BatchedInterface` will compute the union of all symbols and associate each symbol with
@@ -17,7 +17,7 @@ be retained internally.
 `BatchedInterface` implements [`variable_symbols`](@ref), [`is_variable`](@ref),
 [`variable_index`](@ref) to query the order of symbols in the union.
 
-See [`getu`](@ref) and [`setu`](@ref) for further details.
+See [`getsym`](@ref) and [`setsym`](@ref) for further details.
 
 See also: [`associated_systems`](@ref).
 """
@@ -118,7 +118,7 @@ is the index of the index provider associated with the corresponding symbol in
 associated_systems(bi::BatchedInterface) = bi.associated_systems
 
 """
-    getu(bi::BatchedInterface)
+    getsym(bi::BatchedInterface)
 
 Given a [`BatchedInterface`](@ref) composed from `n` index providers (and corresponding
 symbols), return a function which takes `n` corresponding value providers and returns an
@@ -127,7 +127,7 @@ an `AbstractArray` of the appropriate `eltype` and size as its first argument, i
 case the operation will populate the array in-place with the values of the symbols in the
 union.
 
-Note that all of the value providers passed to the function returned by `getu` must satisfy
+Note that all of the value providers passed to the function returned by `getsym` must satisfy
 `is_timeseries(prob) === NotTimeseries()`.
 
 The value of the `i`th symbol in the union (obtained through `variable_symbols(bi)[i]`) is
@@ -137,7 +137,7 @@ provider at index `associated_systems(bi)[i]`).
 See also: [`variable_symbols`](@ref), [`associated_systems`](@ref), [`is_timeseries`](@ref),
 [`NotTimeseries`](@ref).
 """
-function getu(bi::BatchedInterface)
+function getsym(bi::BatchedInterface)
     numprobs = length(bi.system_to_symbol_subset)
     probnames = [Symbol(:prob, i) for i in 1:numprobs]
 
@@ -189,13 +189,13 @@ function getu(bi::BatchedInterface)
 end
 
 """
-    setu(bi::BatchedInterface)
+    setsym(bi::BatchedInterface)
 
 Given a [`BatchedInterface`](@ref) composed from `n` index providers (and corresponding
 symbols), return a function which takes `n` corresponding problems and an array of the
 values, and updates each of the problems with the values of the corresponding symbols.
 
-Note that all of the value providers passed to the function returned by `setu` must satisfy
+Note that all of the value providers passed to the function returned by `setsym` must satisfy
 `is_timeseries(prob) === NotTimeseries()`.
 
 Note that if any subset of the `n` index providers share common symbols (among those passed
@@ -204,7 +204,7 @@ updated with the values of the common symbols.
 
 See also: [`is_timeseries`](@ref), [`NotTimeseries`](@ref).
 """
-function setu(bi::BatchedInterface)
+function setsym(bi::BatchedInterface)
     numprobs = length(bi.system_to_symbol_subset)
     probnames = [Symbol(:prob, i) for i in 1:numprobs]
 
diff --git a/src/parameter_indexing.jl b/src/parameter_indexing.jl
index 1c61f8a..6333cea 100644
--- a/src/parameter_indexing.jl
+++ b/src/parameter_indexing.jl
@@ -726,38 +726,12 @@ function setp_oop(indp, sym)
     return _setp_oop(indp, symtype, elsymtype, sym)
 end
 
-struct OOPSetter{I, D}
-    indp::I
-    idxs::D
-end
-
-function (os::OOPSetter)(valp, val)
-    return remake_buffer(os.indp, parameter_values(valp), (os.idxs,), (val,))
-end
-
-function (os::OOPSetter)(valp, val::Union{Tuple, AbstractArray})
-    if os.idxs isa Union{Tuple, AbstractArray}
-        return remake_buffer(os.indp, parameter_values(valp), os.idxs, val)
-    else
-        return remake_buffer(os.indp, parameter_values(valp), (os.idxs,), (val,))
-    end
-end
-
-function _root_indp(indp)
-    if hasmethod(symbolic_container, Tuple{typeof(indp)}) &&
-       (sc = symbolic_container(indp)) != indp
-        return _root_indp(sc)
-    else
-        return indp
-    end
-end
-
 function _setp_oop(indp, ::NotSymbolic, ::NotSymbolic, sym)
-    return OOPSetter(_root_indp(indp), sym)
+    return OOPSetter(_root_indp(indp), sym, false)
 end
 
 function _setp_oop(indp, ::ScalarSymbolic, ::SymbolicTypeTrait, sym)
-    return OOPSetter(_root_indp(indp), parameter_index(indp, sym))
+    return OOPSetter(_root_indp(indp), parameter_index(indp, sym), false)
 end
 
 for (t1, t2) in [
@@ -765,13 +739,13 @@ for (t1, t2) in [
     (NotSymbolic, Union{<:Tuple, <:AbstractArray})
 ]
     @eval function _setp_oop(indp, ::NotSymbolic, ::$t1, sym::$t2)
-        return OOPSetter(_root_indp(indp), parameter_index.((indp,), sym))
+        return OOPSetter(_root_indp(indp), parameter_index.((indp,), sym), false)
     end
 end
 
 function _setp_oop(indp, ::ArraySymbolic, ::SymbolicTypeTrait, sym)
     if is_parameter(indp, sym)
-        return OOPSetter(_root_indp(indp), parameter_index(indp, sym))
+        return OOPSetter(_root_indp(indp), parameter_index(indp, sym), false)
     end
     error("$sym is not a valid parameter")
 end
diff --git a/src/problem_state.jl b/src/problem_state.jl
index fa93656..831deae 100644
--- a/src/problem_state.jl
+++ b/src/problem_state.jl
@@ -3,7 +3,7 @@
     function ProblemState(; u = nothing, p = nothing, t = nothing)
 
 A value provider struct which can be used as an argument to the function returned by
-[`getu`](@ref) or [`setu`](@ref). It stores the state vector, parameter object and
+[`getsym`](@ref) or [`setsym`](@ref). It stores the state vector, parameter object and
 current time, and forwards calls to [`state_values`](@ref), [`parameter_values`](@ref),
 [`current_time`](@ref), [`set_state!`](@ref), [`set_parameter!`](@ref) to the contained
 objects.
diff --git a/src/remake.jl b/src/remake.jl
index c1dbc47..21de62d 100644
--- a/src/remake.jl
+++ b/src/remake.jl
@@ -46,7 +46,7 @@ function remake_buffer(sys, oldbuffer::AbstractArray, idxs, vals)
             else
                 v = elT(v)
             end
-            setu(sys, k)(newbuffer, v)
+            setsym(sys, k)(newbuffer, v)
         end
     else
         mutbuffer = remake_buffer(sys, collect(oldbuffer), idxs, vals)
@@ -80,7 +80,7 @@ end
 function remake_buffer(sys, oldbuffer::Tuple, idxs, vals)
     wrap = TupleRemakeWrapper(oldbuffer)
     for (idx, val) in zip(idxs, vals)
-        setu(sys, idx)(wrap, val)
+        setsym(sys, idx)(wrap, val)
     end
     return wrap.t
 end
diff --git a/src/state_indexing.jl b/src/state_indexing.jl
index 1945232..b434e4c 100644
--- a/src/state_indexing.jl
+++ b/src/state_indexing.jl
@@ -3,7 +3,7 @@ function set_state!(sys, val, idx)
 end
 
 """
-    getu(indp, sym)
+    getsym(indp, sym)
 
 Return a function that takes a value provider and returns the value of the symbolic
 variable `sym`. If `sym` is not an observed quantity, the returned function can also
@@ -25,10 +25,10 @@ If the value provider is a parameter timeseries object, the same rules apply as
 [`getp`](@ref). The difference here is that `sym` may also contain non-parameter symbols,
 and the values are always returned corresponding to the state timeseries.
 """
-function getu(sys, sym)
+function getsym(sys, sym)
     symtype = symbolic_type(sym)
     elsymtype = symbolic_type(eltype(sym))
-    _getu(sys, symtype, elsymtype, sym)
+    _getsym(sys, symtype, elsymtype, sym)
 end
 
 struct GetStateIndex{I} <: AbstractStateGetIndexer
@@ -47,7 +47,7 @@ function (gsi::GetStateIndex)(::NotTimeseries, prob)
     state_values(prob, gsi.idx)
 end
 
-function _getu(sys, ::NotSymbolic, ::NotSymbolic, sym)
+function _getsym(sys, ::NotSymbolic, ::NotSymbolic, sym)
     return GetStateIndex(sym)
 end
 
@@ -142,10 +142,10 @@ function (o::TimeIndependentObservedFunction)(::IsTimeseriesTrait, prob)
     return o.obsfn(state_values(prob), parameter_values(prob))
 end
 
-function _getu(sys, ::ScalarSymbolic, ::SymbolicTypeTrait, sym)
+function _getsym(sys, ::ScalarSymbolic, ::SymbolicTypeTrait, sym)
     if is_variable(sys, sym)
         idx = variable_index(sys, sym)
-        return getu(sys, idx)
+        return getsym(sys, idx)
     elseif is_parameter(sys, sym)
         return getp(sys, sym)
     elseif is_independent_variable(sys, sym)
@@ -168,7 +168,7 @@ function _getu(sys, ::ScalarSymbolic, ::SymbolicTypeTrait, sym)
             return getp(sys, sym)
         end
     end
-    error("Invalid symbol $sym for `getu`")
+    error("Invalid symbol $sym for `getsym`")
 end
 
 struct MultipleGetters{I, G} <: AbstractStateGetIndexer
@@ -247,7 +247,7 @@ for (t1, t2) in [
     (ArraySymbolic, Any),
     (NotSymbolic, Union{<:Tuple, <:AbstractArray})
 ]
-    @eval function _getu(sys, ::NotSymbolic, elt::$t1, sym::$t2)
+    @eval function _getsym(sys, ::NotSymbolic, elt::$t1, sym::$t2)
         if isempty(sym)
             return MultipleGetters(ContinuousTimeseries(), sym)
         end
@@ -259,7 +259,7 @@ for (t1, t2) in [
         end
         if !is_time_dependent(sys)
             if num_observed == 0 || num_observed == 1 && sym isa Tuple
-                return MultipleGetters(nothing, getu.((sys,), sym))
+                return MultipleGetters(nothing, getsym.((sys,), sym))
             else
                 obs = observed(sys, sym_arr)
                 getter = TimeIndependentObservedFunction(obs)
@@ -280,7 +280,7 @@ for (t1, t2) in [
         end
 
         if num_observed == 0 || num_observed == 1 && sym isa Tuple
-            getters = getu.((sys,), sym)
+            getters = getsym.((sys,), sym)
             return MultipleGetters(ts_idxs, getters)
         else
             obs = observed(sys, sym_arr)
@@ -297,20 +297,20 @@ for (t1, t2) in [
     end
 end
 
-function _getu(sys, ::ArraySymbolic, ::SymbolicTypeTrait, sym)
+function _getsym(sys, ::ArraySymbolic, ::SymbolicTypeTrait, sym)
     if is_variable(sys, sym)
         idx = variable_index(sys, sym)
-        return getu(sys, idx)
+        return getsym(sys, idx)
     elseif is_parameter(sys, sym)
         return getp(sys, sym)
     end
-    return getu(sys, collect(sym))
+    return getsym(sys, collect(sym))
 end
 
-# setu doesn't need the same `let` blocks to be inferred for some reason
+# setsym doesn't need the same `let` blocks to be inferred for some reason
 
 """
-    setu(sys, sym)
+    setsym(sys, sym)
 
 Return a function that takes a value provider and a value, and sets the the state `sym` to
 that value. Note that `sym` can be an index, a symbolic variable, or an array/tuple of the
@@ -322,10 +322,10 @@ if this is not possible or additional actions need to be performed when updating
 [`set_state!`](@ref) can be defined. This function does not work on types for which
 [`is_timeseries`](@ref) is [`Timeseries`](@ref).
 """
-function setu(sys, sym)
+function setsym(sys, sym)
     symtype = symbolic_type(sym)
     elsymtype = symbolic_type(eltype(sym))
-    _setu(sys, symtype, elsymtype, sym)
+    _setsym(sys, symtype, elsymtype, sym)
 end
 
 struct SetStateIndex{I} <: AbstractSetIndexer
@@ -336,18 +336,18 @@ function (ssi::SetStateIndex)(prob, val)
     set_state!(prob, val, ssi.idx)
 end
 
-function _setu(sys, ::NotSymbolic, ::NotSymbolic, sym)
+function _setsym(sys, ::NotSymbolic, ::NotSymbolic, sym)
     return SetStateIndex(sym)
 end
 
-function _setu(sys, ::ScalarSymbolic, ::SymbolicTypeTrait, sym)
+function _setsym(sys, ::ScalarSymbolic, ::SymbolicTypeTrait, sym)
     if is_variable(sys, sym)
         idx = variable_index(sys, sym)
         return SetStateIndex(idx)
     elseif is_parameter(sys, sym)
         return setp(sys, sym)
     end
-    error("Invalid symbol $sym for `setu`")
+    error("Invalid symbol $sym for `setsym`")
 end
 
 for (t1, t2) in [
@@ -355,13 +355,13 @@ for (t1, t2) in [
     (ArraySymbolic, Any),
     (NotSymbolic, Union{<:Tuple, <:AbstractArray})
 ]
-    @eval function _setu(sys, ::NotSymbolic, ::$t1, sym::$t2)
-        setters = setu.((sys,), sym)
+    @eval function _setsym(sys, ::NotSymbolic, ::$t1, sym::$t2)
+        setters = setsym.((sys,), sym)
         return MultipleSetters(setters)
     end
 end
 
-function _setu(sys, ::ArraySymbolic, ::SymbolicTypeTrait, sym)
+function _setsym(sys, ::ArraySymbolic, ::SymbolicTypeTrait, sym)
     if is_variable(sys, sym)
         idx = variable_index(sys, sym)
         if idx isa AbstractArray
@@ -372,5 +372,102 @@ function _setu(sys, ::ArraySymbolic, ::SymbolicTypeTrait, sym)
     elseif is_parameter(sys, sym)
         return setp(sys, sym)
     end
-    return setu(sys, collect(sym))
+    return setsym(sys, collect(sym))
+end
+
+const getu = getsym
+const setu = setsym
+
+"""
+    setsym_oop(indp, sym)
+
+Return a function which takes a value provider `valp` and a value `val`, and returns
+`state_values(valp), parameter_values(valp)` with the states/parameters in `sym` set to the
+corresponding values in `val`. This allows changing the types of values stored, and leverages
+[`remake_buffer`](@ref). Note that `sym` can be an index, a symbolic variable, or an
+array/tuple of the aforementioned. All entries `s` in `sym` must satisfy `is_variable(indp, s)`
+or `is_parameter(indp, s)`.
+
+Requires that the value provider implement `state_values`, `parameter_values` and `remake_buffer`.
+"""
+function setsym_oop(indp, sym)
+    symtype = symbolic_type(sym)
+    elsymtype = symbolic_type(eltype(sym))
+    return _setsym_oop(indp, symtype, elsymtype, sym)
+end
+
+struct FullSetter{S, P, I, J}
+    state_setter::S
+    param_setter::P
+    state_split::I
+    param_split::J
+end
+
+FullSetter(ssetter, psetter) = FullSetter(ssetter, psetter, nothing, nothing)
+
+function (fs::FullSetter)(valp, val)
+    return fs.state_setter(valp, val[fs.state_split]),
+    fs.param_setter(valp, val[fs.param_split])
+end
+
+function (fs::FullSetter{Nothing})(valp, val)
+    return state_values(valp), fs.param_setter(valp, val)
+end
+
+function (fs::(FullSetter{S, Nothing} where {S}))(valp, val)
+    return fs.state_setter(valp, val), parameter_values(valp)
+end
+
+function (fs::(FullSetter{Nothing, Nothing}))(valp, val)
+    return state_values(valp), parameter_values(valp)
+end
+
+function _setsym_oop(indp, ::NotSymbolic, ::NotSymbolic, sym)
+    return FullSetter(OOPSetter(_root_indp(indp), sym, true), nothing)
+end
+
+function _setsym_oop(indp, ::ScalarSymbolic, ::SymbolicTypeTrait, sym)
+    if (idx = variable_index(indp, sym)) !== nothing
+        return FullSetter(OOPSetter(_root_indp(indp), idx, true), nothing)
+    elseif (idx = parameter_index(indp, sym)) !== nothing
+        return FullSetter(nothing, OOPSetter(_root_indp(indp), idx, false))
+    end
+    throw(NotVariableOrParameter("setsym_oop", sym))
+end
+
+for (t1, t2) in [
+    (ScalarSymbolic, Any),
+    (NotSymbolic, Union{<:Tuple, <:AbstractArray})
+]
+    @eval function _setsym_oop(indp, ::NotSymbolic, ::$t1, sym::$t2)
+        vars = []
+        state_split = eltype(eachindex(sym))[]
+        pars = []
+        param_split = eltype(eachindex(sym))[]
+        for (i, s) in enumerate(sym)
+            if (idx = variable_index(indp, s)) !== nothing
+                push!(vars, idx)
+                push!(state_split, i)
+            elseif (idx = parameter_index(indp, s)) !== nothing
+                push!(pars, idx)
+                push!(param_split, i)
+            else
+                throw(NotVariableOrParameter("setsym_oop", s))
+            end
+        end
+        indp = _root_indp(indp)
+        return FullSetter(isempty(vars) ? nothing : OOPSetter(indp, identity.(vars), true),
+            isempty(pars) ? nothing : OOPSetter(indp, identity.(pars), false),
+            state_split, param_split)
+    end
+end
+
+function _setsym_oop(indp, ::ArraySymbolic, ::SymbolicTypeTrait, sym)
+    if (idx = variable_index(indp, sym)) !== nothing
+        return setsym_oop(indp, idx)
+    elseif (idx = parameter_index(indp, sym)) !== nothing
+        return FullSetter(
+            nothing, OOPSetter(indp, idx isa AbstractArray ? idx : (idx,), false))
+    end
+    return setsym_oop(indp, collect(sym))
 end
diff --git a/src/value_provider_interface.jl b/src/value_provider_interface.jl
index 1ae30b5..cd52ae1 100644
--- a/src/value_provider_interface.jl
+++ b/src/value_provider_interface.jl
@@ -110,7 +110,7 @@ state_values(arr, ::Colon) = state_values(arr)
 Set the state at index `idx` to `val` for value provider `valp`. This defaults to modifying
 `state_values(valp)`. If any additional bookkeeping needs to be performed or the
 default implementation does not work for a particular type, this method needs to be
-defined to enable the proper functioning of [`setu`](@ref).
+defined to enable the proper functioning of [`setsym`](@ref).
 
 See: [`state_values`](@ref)
 """
@@ -231,6 +231,35 @@ function (fn::Fix1Multiple)(args...)
     fn.f(fn.arg, args...)
 end
 
+struct OOPSetter{I, D}
+    indp::I
+    idxs::D
+    is_state::Bool
+end
+
+function (os::OOPSetter)(valp, val)
+    buffer = os.is_state ? state_values(valp) : parameter_values(valp)
+    return remake_buffer(os.indp, buffer, (os.idxs,), (val,))
+end
+
+function (os::OOPSetter)(valp, val::Union{Tuple, AbstractArray})
+    buffer = os.is_state ? state_values(valp) : parameter_values(valp)
+    if os.idxs isa Union{Tuple, AbstractArray}
+        return remake_buffer(os.indp, buffer, os.idxs, val)
+    else
+        return remake_buffer(os.indp, buffer, (os.idxs,), (val,))
+    end
+end
+
+function _root_indp(indp)
+    if hasmethod(symbolic_container, Tuple{typeof(indp)}) &&
+       (sc = symbolic_container(indp)) != indp
+        return _root_indp(sc)
+    else
+        return indp
+    end
+end
+
 ###########
 # Errors
 ###########
@@ -296,3 +325,16 @@ function Base.showerror(io::IO, err::MixedParameterTimeseriesIndexError)
         indexes $(err.ts_idxs).
     """)
 end
+
+struct NotVariableOrParameter <: Exception
+    fn::Any
+    sym::Any
+end
+
+function Base.showerror(io::IO, err::NotVariableOrParameter)
+    print(
+        io, """
+      `$(err.fn)` requires that the symbolic variable(s) passed to it satisfy `is_variable`
+      or `is_parameter`. Got `$(err.sym)` which is neither.
+  """)
+end
diff --git a/test/batched_interface_test.jl b/test/batched_interface_test.jl
index 13dd415..533ef61 100644
--- a/test/batched_interface_test.jl
+++ b/test/batched_interface_test.jl
@@ -28,13 +28,13 @@ bi = BatchedInterface(zip(syss, syms)...)
       Bool[1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0]
 @test associated_systems(bi) == [1, 1, 1, 1, 2, 2, 3, 3]
 
-getter = getu(bi)
+getter = getsym(bi)
 @test (@inferred getter(probs...)) == [1.0, 3.0, 0.2, 0.3, 5.0, 0.6, 0.7, 0.8]
 buf = zeros(8)
 @inferred getter(buf, probs...)
 @test buf == [1.0, 3.0, 0.2, 0.3, 5.0, 0.6, 0.7, 0.8]
 
-setter! = setu(bi)
+setter! = setsym(bi)
 buf .*= 100
 setter!(probs..., buf)
 
diff --git a/test/downstream/batchedinterface_arrayvars.jl b/test/downstream/batchedinterface_arrayvars.jl
index eaba28c..f07edc5 100644
--- a/test/downstream/batchedinterface_arrayvars.jl
+++ b/test/downstream/batchedinterface_arrayvars.jl
@@ -23,13 +23,13 @@ bi = BatchedInterface(zip(syss, syms)...)
 @test is_variable.((bi,), [x..., y, z]) == Bool[1, 1, 1, 0]
 @test associated_systems(bi) == [1, 1, 1]
 
-getter = getu(bi)
+getter = getsym(bi)
 @test (@inferred getter(probs...)) == [1.0, 2.0, 3.0]
 buf = zeros(3)
 @inferred getter(buf, probs...)
 @test buf == [1.0, 2.0, 3.0]
 
-setter! = setu(bi)
+setter! = setsym(bi)
 buf .*= 10
 setter!(probs..., buf)
 
@@ -58,7 +58,7 @@ probs = [
 
 bi = BatchedInterface(zip(syss, syms)...)
 
-buf = getu(bi)(probs...)
+buf = getsym(bi)(probs...)
 buf .*= 100
 setter = setsym_oop(bi)
 vals = setter(probs..., buf)
diff --git a/test/parameter_indexing_test.jl b/test/parameter_indexing_test.jl
index 6c864c4..26eaaf5 100644
--- a/test/parameter_indexing_test.jl
+++ b/test/parameter_indexing_test.jl
@@ -488,7 +488,7 @@ for (sym, val_is_timeseries, val, check_inference) in [
     ([:a, :(2b)], true, vcat.(aval, 2 .* bval), true),
     ((:a, :(2b)), true, tuple.(aval, 2 .* bval), true)
 ]
-    getter = getu(sys, sym)
+    getter = getsym(sys, sym)
     if check_inference
         @inferred getter(fs)
     end
@@ -524,7 +524,7 @@ for (sym, val, check_inference) in [
     ([:(2b), :(3x)], [2_bval, 3_xval], true),
     ((:(2b), :(3x)), (2_bval, 3_xval), true)
 ]
-    getter = getu(sys, sym)
+    getter = getsym(sys, sym)
     @test_throws MixedParameterTimeseriesIndexError getter(fs)
     for subidx in [1, CartesianIndex(2), :, rand(Bool, 4), rand(1:4, 3), 1:2]
         @test_throws MixedParameterTimeseriesIndexError getter(fs, subidx)
diff --git a/test/problem_state_test.jl b/test/problem_state_test.jl
index d060925..906ee73 100644
--- a/test/problem_state_test.jl
+++ b/test/problem_state_test.jl
@@ -5,11 +5,11 @@ sys = SymbolCache([:x, :y, :z], [:a, :b, :c], :t)
 prob = ProblemState(; u = [1.0, 2.0, 3.0], p = [0.1, 0.2, 0.3], t = 0.5)
 
 for (i, sym) in enumerate(variable_symbols(sys))
-    @test getu(sys, sym)(prob) == prob.u[i]
+    @test getsym(sys, sym)(prob) == prob.u[i]
 end
 for (i, sym) in enumerate(parameter_symbols(sys))
     @test getp(sys, sym)(prob) == prob.p[i]
 end
-@test getu(sys, :t)(prob) == prob.t
+@test getsym(sys, :t)(prob) == prob.t
 
-@test getu(sys, :(x + a + t))(prob) == 1.6
+@test getsym(sys, :(x + a + t))(prob) == 1.6
diff --git a/test/simple_adjoints_test.jl b/test/simple_adjoints_test.jl
index 329fd10..c3fc2c1 100644
--- a/test/simple_adjoints_test.jl
+++ b/test/simple_adjoints_test.jl
@@ -4,14 +4,14 @@ using Zygote
 sys = SymbolCache([:x, :y, :z], [:a, :b, :c], :t)
 pstate = ProblemState(; u = rand(3), p = rand(3), t = rand())
 
-getter = getu(sys, :x)
+getter = getsym(sys, :x)
 @test Zygote.gradient(getter, pstate)[1].u == [1.0, 0.0, 0.0]
 
-getter = getu(sys, [:x, :z])
+getter = getsym(sys, [:x, :z])
 @test Zygote.gradient(sum ∘ getter, pstate)[1].u == [1.0, 0.0, 1.0]
 
-getter = getu(sys, :a)
+getter = getsym(sys, :a)
 @test Zygote.gradient(getter, pstate)[1].p == [1.0, 0.0, 0.0]
 
-getter = getu(sys, [:a, :c])
+getter = getsym(sys, [:a, :c])
 @test Zygote.gradient(sum ∘ getter, pstate)[1].p == [1.0, 0.0, 1.0]
diff --git a/test/state_indexing_test.jl b/test/state_indexing_test.jl
index 8e59779..622e5b1 100644
--- a/test/state_indexing_test.jl
+++ b/test/state_indexing_test.jl
@@ -1,4 +1,5 @@
 using SymbolicIndexingInterface
+using SymbolicIndexingInterface: NotVariableOrParameter
 
 struct FakeIntegrator{S, U, P, T}
     sys::S
@@ -14,8 +15,8 @@ SymbolicIndexingInterface.current_time(fp::FakeIntegrator) = fp.t
 
 sys = SymbolCache([:x, :y, :z], [:a, :b, :c], [:t])
 
-@test_throws ErrorException getu(sys, :q)
-@test_throws ErrorException setu(sys, :q)
+@test_throws ErrorException getsym(sys, :q)
+@test_throws ErrorException setsym(sys, :q)
 
 u = [1.0, 2.0, 3.0]
 p = [11.0, 12.0, 13.0]
@@ -50,8 +51,8 @@ for (sym, val, newval, check_inference) in [(:x, u[1], 4.0, true)
                                                 (4.0, (5.0, 6.0)), true)
                                             ((:x, [:y], (:z,)), (u[1], [u[2]], (u[3],)),
                                                 (4.0, [5.0], (6.0,)), true)]
-    get = getu(sys, sym)
-    set! = setu(sys, sym)
+    get = getsym(sys, sym)
+    set! = setsym(sys, sym)
     if check_inference
         @inferred get(fi)
     end
@@ -62,6 +63,9 @@ for (sym, val, newval, check_inference) in [(:x, u[1], 4.0, true)
         set!(fi, newval)
     end
     @test get(fi) == newval
+
+    new_states = copy(state_values(fi))
+
     set!(fi, val)
     @test get(fi) == val
 
@@ -77,6 +81,15 @@ for (sym, val, newval, check_inference) in [(:x, u[1], 4.0, true)
     @test get(u) == newval
     set!(u, val)
     @test get(u) == val
+
+    if sym isa Union{Vector, Tuple} && any(x -> x isa Union{AbstractArray, Tuple}, sym)
+        continue
+    end
+
+    setter = setsym_oop(sys, sym)
+    svals, pvals = setter(fi, newval)
+    @test svals ≈ new_states
+    @test pvals == parameter_values(fi)
 end
 
 for (sym, val, check_inference) in [
@@ -84,7 +97,7 @@ for (sym, val, check_inference) in [
     ([:(x + y), :z], [u[1] + u[2], u[3]], false),
     ((:(x + y), :(z + y)), (u[1] + u[2], u[2] + u[3]), false)
 ]
-    get = getu(sys, sym)
+    get = getsym(sys, sym)
     if check_inference
         @inferred get(fi)
     end
@@ -92,15 +105,15 @@ for (sym, val, check_inference) in [
 end
 
 let fi = fi, sys = sys
-    getter = getu(sys, [])
+    getter = getsym(sys, [])
     @test getter(fi) == []
-    getter = getu(sys, ())
+    getter = getsym(sys, ())
     @test getter(fi) == ()
     sc = SymbolCache(nothing, [:a, :b], :t)
     fi = FakeIntegrator(sys, nothing, [1.0, 2.0], 3.0)
-    getter = getu(sc, [])
+    getter = getsym(sc, [])
     @test getter(fi) == []
-    getter = getu(sc, ())
+    getter = getsym(sc, ())
     @test getter(fi) == ()
 end
 
@@ -111,8 +124,8 @@ for (sym, oldval, newval, check_inference) in [(:a, p[1], 4.0, true)
                                                ((:c, :b), (p[3], p[2]), (6.0, 5.0), true)
                                                ([:x, :a], [u[1], p[1]], [4.0, 5.0], false)
                                                ((:y, :b), (u[2], p[2]), (5.0, 6.0), true)]
-    get = getu(fi, sym)
-    set! = setu(fi, sym)
+    get = getsym(fi, sym)
+    set! = setsym(fi, sym)
     if check_inference
         @inferred get(fi)
     end
@@ -123,8 +136,17 @@ for (sym, oldval, newval, check_inference) in [(:a, p[1], 4.0, true)
         set!(fi, newval)
     end
     @test get(fi) == newval
+
+    newu = copy(state_values(fi))
+    newp = copy(parameter_values(fi))
+
     set!(fi, oldval)
     @test get(fi) == oldval
+
+    oop_setter = setsym_oop(sys, sym)
+    uvals, pvals = oop_setter(fi, newval)
+    @test uvals ≈ newu
+    @test pvals ≈ newp
 end
 
 for (sym, val, check_inference) in [
@@ -132,11 +154,13 @@ for (sym, val, check_inference) in [
     ([:x, :a, :t], [u[1], p[1], t], false),
     ((:x, :a, :t), (u[1], p[1], t), false)
 ]
-    get = getu(fi, sym)
+    get = getsym(fi, sym)
     if check_inference
         @inferred get(fi)
     end
     @test get(fi) == val
+
+    @test_throws NotVariableOrParameter setsym_oop(fi, sym)
 end
 
 struct FakeSolution{S, U, P, T}
@@ -202,7 +226,7 @@ for (sym, ans, check_inference) in [(:x, xvals, true)
                                     (:t, t, true)
                                     ([:x, :a, :t], vcat.(xvals, p[1], t), false)
                                     ((:x, :a, :t), tuple.(xvals, p[1], t), true)]
-    get = getu(sys, sym)
+    get = getsym(sys, sym)
     if check_inference
         @inferred get(sol)
     end
@@ -221,7 +245,7 @@ for (sym, val, check_inference) in [
     ([:(x + y), :z], vcat.(xvals .+ yvals, zvals), false),
     ((:(x + y), :(z + y)), tuple.(xvals .+ yvals, yvals .+ zvals), false)
 ]
-    get = getu(sys, sym)
+    get = getsym(sys, sym)
     if check_inference
         @inferred get(sol)
     end
@@ -240,21 +264,21 @@ for (sym, val) in [(:a, p[1])
                    (:c, p[3])
                    ([:a, :b], p[1:2])
                    ((:c, :b), (p[3], p[2]))]
-    get = getu(sys, sym)
+    get = getsym(sys, sym)
     @inferred get(sol)
     @test get(sol) == val
 end
 
 let sol = sol, sys = sys
-    getter = getu(sys, [])
+    getter = getsym(sys, [])
     @test getter(sol) == [[] for _ in 1:length(sol.t)]
-    getter = getu(sys, ())
+    getter = getsym(sys, ())
     @test getter(sol) == [() for _ in 1:length(sol.t)]
     sc = SymbolCache(nothing, [:a, :b], :t)
     sol = FakeSolution(sys, [], [1.0, 2.0], [])
-    getter = getu(sc, [])
+    getter = getsym(sc, [])
     @test getter(sol) == []
-    getter = getu(sc, ())
+    getter = getsym(sc, ())
     @test getter(sol) == []
 end
 
@@ -285,7 +309,7 @@ for (sym, val, check_inference) in [
     ([:(x + a), :(y + b)], [u[1] + p[1], u[2] + p[2]], true),
     ((:(x + a), :(y + b)), (u[1] + p[1], u[2] + p[2]), true)
 ]
-    getter = getu(sys, sym)
+    getter = getsym(sys, sym)
     if check_inference
         @inferred getter(fs)
     end
@@ -318,7 +342,7 @@ ts = 0.0:0.1:1.0
 
 fi = FakeIntegrator(sys, u0, p, ts[1])
 fs = FakeSolution(sys, u, p, ts)
-getter = getu(sys, :(x + y))
+getter = getsym(sys, :(x + y))
 @test getter(fi) ≈ 2.8
 @test getter(fs) ≈ [3.0i + 2(ts[i] - 0.1) for i in 1:11]
 @test getter(fs, 1) ≈ 2.8