diff --git a/src/JuliaFEM.jl b/src/JuliaFEM.jl
index b33bbf6..c279b0a 100644
--- a/src/JuliaFEM.jl
+++ b/src/JuliaFEM.jl
@@ -430,9 +430,22 @@ include("assemblers/nodal_based.jl")
 # LEVEL 5: PHYSICAL DOMAINS (Domain-specific assembly kernels)
 # ============================================================================
 
+# ============================================================================
+# COMMON DOMAIN UTILITIES (Shared across all domain types)
+# ============================================================================
+
+# Boundary conditions (generic - work with any kernel/domain)
+include("domains/common/boundary_conditions.jl")
+export apply_neumann_bcs!, apply_dirichlet_bcs!  # Explicit BC application
+
+# ============================================================================
+# CONTINUUM MECHANICS DOMAIN
+# ============================================================================
+
 # Continuum mechanics kernel
 include("domains/continuum/kernel.jl")
 export ContinuumKernel
+export PreparedElement, prepare_element!, compute_block!, compute_block_at_point  # Block API
 
 # Continuum assembly (uses generic assemblers)
 include("domains/continuum/assemble.jl")