diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9687e11..79f48a5 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -29,11 +29,11 @@ jobs:
     steps:
       - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
 
-      - uses: julia-actions/setup-julia@4c0cb0fce8556fdb04a90347310e5db8b1f98fb9 # v2
+      - uses: julia-actions/setup-julia@fa02766e078afaaf09b14210362cee14137e6a32 # v3.0.2
         with:
           version: ${{ matrix.julia-version }}
 
-      - uses: julia-actions/cache@e33b4bfa0ea7cd9caedd7cb82b0e36956ef40285 # v2
+      - uses: julia-actions/cache@a45e8fa8be21c18a06b7177052533149e61e9b38 # v3.1.0
 
       - name: Install, build, test
         run: julia --project=. -e 'using Pkg; Pkg.Registry.add("General"); Pkg.Registry.add(Pkg.RegistrySpec(url="https://github.com/hyperpolymath/julia-professional-registry.git")); Pkg.instantiate(); Pkg.build(); Pkg.test()'
diff --git a/src/PostDisciplinary.jl b/src/PostDisciplinary.jl
index 2598c39..5eb8037 100644
--- a/src/PostDisciplinary.jl
+++ b/src/PostDisciplinary.jl
@@ -30,7 +30,6 @@ using JSON3
 
 include("consensus/raft.jl")
 include("meta_analysis.jl")
-include("synthesis/diffing.jl")
 include("memetics.jl")
 include("methodology.jl")
 include("storage/verisim.jl")
@@ -45,7 +44,6 @@ include("synthesis/templates.jl")
 
 using .RaftConsensus
 using .MetaAnalysis
-using .KnowledgeDiffing
 using .Memetics
 using .Methodology
 using .VeriSimBridge
@@ -150,4 +148,9 @@ function generate_synthesis(p::ResearchProject)
     )
 end
 
+# KnowledgeDiffing refers to the public ResearchProject and LinkedEntity types,
+# so load it after those types have been defined.
+include("synthesis/diffing.jl")
+using .KnowledgeDiffing
+
 end # module