diff --git a/Project.toml b/Project.toml
index 2f1be08..ccd5460 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "GTPSA"
 uuid = "b27dd330-f138-47c5-815b-40db9dd9b6e8"
 authors = ["Matt Signorelli"]
-version = "1.1.0"
+version = "1.1.1"
 
 [deps]
 GTPSA_jll = "a4739e29-4b97-5c0b-bbcf-46f08034c990"
diff --git a/src/getset.jl b/src/getset.jl
index 3f75c14..b259892 100644
--- a/src/getset.jl
+++ b/src/getset.jl
@@ -492,7 +492,7 @@ end
 
 
 """
-    GTPSA.hessian!(result, t::TPS; include_params=false)
+    GTPSA.hessian!(result, t::TPS; include_params=false, tmp_mono::Union{Nothing,Vector{UInt8}}=nothing, unsafe_fast::Bool=false)
 
 Extracts the second-order partial derivatives (evaluated at 0) from the TPS 
 and fills the `result` matrix in-place. The partial derivatives wrt the parameters will 
@@ -503,11 +503,13 @@ in the TPS.
 ### Input
 - `t`              -- `TPS`/`ComplexTPS64` to extract the Hessian from
 - `include_params` -- (Optional) Extract partial derivatives wrt parameters. Default is false
+- `tmp_mono`       -- (Optional) `Vector{UInt8}` to store the monomial, when different orders of truncation are used
+- `unsafe_fast`    -- (Optional) Flag to specify that "fast" indexing should be used without checking. This will give incorrect results if any variable has a TO < 2. Default is `false`.
 
 ### Output
 - `result`         -- Matrix to fill with the Hessian of the TPS, must be 1-based indexing
 """
-function hessian!(result, t::TPS; include_params=false)
+function hessian!(result, t::TPS; include_params=false, tmp_mono::Union{Nothing,Vector{UInt8}}=nothing, unsafe_fast::Bool=false)
   Base.require_one_based_indexing(result)
   desc = unsafe_load(t.d)
   n = desc.nv
@@ -520,16 +522,18 @@ function hessian!(result, t::TPS; include_params=false)
 
   # If all variables/variable+parameters have truncation order > 2, then 
   # the indexing is known beforehand and we can do it faster
-  check = true
-  i = 1
-  while check && i <= n
-    if unsafe_load(desc.no, i) < 0x2
-      check = false
+  fast = true
+  if !unsafe_fast
+    i = 1
+    while fast && i <= n
+      if unsafe_load(desc.no, i) < 0x2
+        fast = false  # use "slow" indexing
+      end
+      i += 1
     end
-    i += 1
   end
-  #check=false
-  if check
+  
+  if fast
     idx = desc.nv+desc.np
     endidx = floor(n*(n+1)/2)+nn
     curdiag = 1
@@ -559,7 +563,12 @@ function hessian!(result, t::TPS; include_params=false)
     # of the Hessian itself (this is just a getter)  
     idx = desc.nv+desc.np # start at 2nd order
     v = Ref{eltype(t)}()
-    mono = Vector{UInt8}(undef, nn)
+    if isnothing(tmp_mono)
+      mono = Vector{UInt8}(undef, nn)
+    else
+      length(tmp_mono) == nn || error("length(tmp_mono) must be $nn, received $(length(tmp_mono))")
+      mono = tmp_mono
+    end
     idx = cycle!(t, idx, nn, mono, v)
     while idx > 0 
       if sum(mono) > 0x2