diff --git a/.github/workflows/benchmarks.yml b/.github/workflows/benchmarks.yml
index 5a11f6f2f..9c1b4bd8c 100644
--- a/.github/workflows/benchmarks.yml
+++ b/.github/workflows/benchmarks.yml
@@ -8,7 +8,7 @@ jobs:
       - name: Set up Julia
         uses: julia-actions/setup-julia@latest
         with:
-          version: 1.6
+          version: 1.7
       - name: Install dependencies
         run: julia -e 'using Pkg; pkg"add PkgBenchmark BenchmarkCI@0.1"'
       - name: Run benchmarks
diff --git a/.github/workflows/codecov.yml b/.github/workflows/codecov.yml
index 425d6765e..0b84c4cf1 100644
--- a/.github/workflows/codecov.yml
+++ b/.github/workflows/codecov.yml
@@ -9,7 +9,7 @@ jobs:
       - uses: actions/checkout@v2
       - uses: julia-actions/setup-julia@latest
         with:
-          version: '1.6'
+          version: '1.7'
       - name: "Install system dependencies"
         run: |
           sudo apt-get update
diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index 29a5b7b62..506a62ccf 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -8,7 +8,7 @@ jobs:
       - name: "Set up Julia"
         uses: julia-actions/setup-julia@latest
         with:
-          version: '1.6'
+          version: '1.7'
       - name: "Install system dependencies"
         run: |
           sudo apt-get update
diff --git a/.github/workflows/downstream.yml b/.github/workflows/downstream.yml
index f147b60fb..b6a1b610f 100644
--- a/.github/workflows/downstream.yml
+++ b/.github/workflows/downstream.yml
@@ -7,7 +7,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        julia-version: ['1.6']
+        julia-version: ['1.7']
         os: [ubuntu-latest]
         package:
           - {user: AlgebraicJulia, repo: AlgebraicDynamics.jl}
diff --git a/.github/workflows/experiments.yml b/.github/workflows/experiments.yml
index 64b1b403f..7a4da5da3 100644
--- a/.github/workflows/experiments.yml
+++ b/.github/workflows/experiments.yml
@@ -13,7 +13,7 @@ jobs:
       - name: "Set up Julia"
         uses: julia-actions/setup-julia@latest
         with:
-          version: '1.6'
+          version: '1.7'
       # XXX: Cannot change working directory for "uses" steps.
       #- name: "Run tests"
       #  uses: julia-actions/julia-runtest@master
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 5ef155485..a6f089257 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -6,7 +6,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        julia_version: ['1.6']
+        julia_version: ['1.6', '1.7']
         os: [ubuntu-latest]
     steps:
       - uses: actions/checkout@v2
diff --git a/src/categorical_algebra/CatElements.jl b/src/categorical_algebra/CatElements.jl
index 648cef1f9..4783b0b6c 100644
--- a/src/categorical_algebra/CatElements.jl
+++ b/src/categorical_algebra/CatElements.jl
@@ -1,6 +1,8 @@
 module CatElements
 export ThElements, AbstractElements, Elements, elements
 
+using DataStructures: OrderedDict
+
 using ..CSets, ..FinSets
 using ...Present, ...Theories
 using ...Theories: Category, ob, hom, dom_nums, codom_nums
@@ -59,7 +61,7 @@ will be mapped to `src_E_1, tgt_E_1`.
 """
 function presentation(X::AbstractElements)
   P = Presentation(FreeSchema)
-  obs = Dict{Tuple{Symbol, Int}, Any}()
+  obs = OrderedDict{Tuple{Symbol, Int}, Any}()
   for a in 1:nparts(X, :Ob)
     class = X[a, :nameo]
     for (i,j) in enumerate(incident(X, a, :πₑ))
@@ -68,7 +70,7 @@ function presentation(X::AbstractElements)
     end
   end
   add_generators!(P, values(obs))
-  homs = Dict{Tuple{Symbol, Int}, Any}()
+  homs = OrderedDict{Tuple{Symbol, Int}, Any}()
   for f in 1:nparts(X, :Hom)
     class = X[f, :nameh]
     for (i,j) in enumerate(incident(X, f, :πₐ))
diff --git a/src/wiring_diagrams/Algebras.jl b/src/wiring_diagrams/Algebras.jl
index 002fa09dc..530084cb6 100644
--- a/src/wiring_diagrams/Algebras.jl
+++ b/src/wiring_diagrams/Algebras.jl
@@ -22,9 +22,10 @@ box/junction attributes. The default attributes are those compatible with the
 function oapply(composite::UndirectedWiringDiagram, hom_map::AbstractDict,
                 ob_map::Union{AbstractDict,Nothing}=nothing;
                 hom_attr::Symbol=:name, ob_attr::Symbol=:variable)
-  homs = [ hom_map[name] for name in subpart(composite, hom_attr) ]
+  # XXX: Julia should be inferring these vector eltypes but isn't on v1.7.
+  homs = valtype(hom_map)[ hom_map[name] for name in composite[hom_attr] ]
   obs = isnothing(ob_map) ? nothing :
-    [ ob_map[name] for name in subpart(composite, ob_attr) ]
+    valtype(ob_map)[ ob_map[name] for name in composite[ob_attr] ]
   oapply(composite, homs, obs)
 end
 
@@ -99,7 +100,9 @@ function oapply(composite::UndirectedWiringDiagram,
       end
     end
   end
-  diagram[:ob₁] = map(L, junction_feet)
+  for (j, foot) in enumerate(junction_feet)
+    diagram[j, :ob₁] = L(foot)
+  end
 
   # Find, or if necessary create, an outgoing edge for each junction. The
   # existence of such edges is an assumption for colimits of bipartite diagrams.
diff --git a/test/categorical_algebra/CatElements.jl b/test/categorical_algebra/CatElements.jl
index fb287d3cf..e7ddf5fee 100644
--- a/test/categorical_algebra/CatElements.jl
+++ b/test/categorical_algebra/CatElements.jl
@@ -32,7 +32,7 @@ b = @acset Graph begin
 end
 
 ThBPG, obmap, hommap = CatElements.presentation(elements(b))
-@test Symbol.(generators(ThBPG)) == [:E_1, :V_1, :V_2, :tgt_E_1, :src_E_1]
+@test Symbol.(generators(ThBPG)) == [:V_1, :V_2, :E_1, :src_E_1, :tgt_E_1]
 
 
 p₀ = @acset Graph begin
@@ -43,7 +43,8 @@ p₀ = @acset Graph begin
 end
 
 ThPetri, obmap, hommap = CatElements.presentation(elements(p₀))
-@test Symbol.(generators(ThPetri)) == [:E_1, :E_2, :V_1, :V_2, :src_E_2, :tgt_E_1, :tgt_E_2, :src_E_1]
+@test Symbol.(generators(ThPetri)) ==
+  [:V_1, :V_2, :E_1, :E_2, :src_E_1, :src_E_2, :tgt_E_1, :tgt_E_2]
 
 @acset_type Petri(ThPetri)