fix(build): stub ActualTypes hub + patch importers to avoid 274 MB .hi crash

Generated.ActualTypes uses `module M` re-export syntax for 61 sub-modules;
GHC 9.10.3 embeds all 61 full sub-interfaces into ActualTypes.hi (~287 MB),
hitting the binary-deserialization limit at position 287686318.

Revert Cabal sub-library split (did not help — models-inner also crashed
with only 61 modules at the same invariant position). Apply the same fix
already working for Generated.Types in inter-hub-lib:

- inter-hub-models postUnpack: stub Generated.ActualTypes.hs + Generated.Types.hs
  to empty modules; patch every importer with direct sub-module imports (reads
  original ActualTypes.hs before stubbing to build the replacement import list)
- inter-hub-lib postUnpack: same for both hubs (each package has its own
  sourceRoot with originals intact)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

flake.nix

@@ -91,18 +91,19 @@
                     # PostgreSQL extensions
                     # services.postgres.extensions = extensions: [ extensions.postgis ];
 
-                    # GHC 9.10.3 crash fix: Generated.Types imports 119 modules, exceeding
+                    # GHC 9.10.3 crash fix: Generated.ActualTypes uses `module M` re-export
-                    # the ~287 MB interface-file binary-deserialization limit.
+                    # syntax for 61 sub-modules; the resulting ActualTypes.hi exceeds GHC's
+                    # ~274 MB binary-deserialization limit (crash at position 287686318).
                     #
                     # pkgs is built from `import nixpkgs { overlays = devenv.shells.default.overlays; }`.
                     # IHP adds ihp.overlays.default to this list, which sets
                     # pkgs.ghc = haskellPackages.override { overrides = ihpOverrides }.
                     # We extend pkgs.ghc with a mkDerivation override (lib.mkAfter ensures
                     # we run after IHP's overlay, so prev.ghc is already IHP's package set).
-                    # 2-way split (60 entities) still crashes — TypesPart1.hi itself hits 287 MB.
+                    # For inter-hub-models: stub Generated.ActualTypes + Generated.Types to
-                    # 4-way split (~30 entities, ~150 MB .hi each) stays safely under the limit.
+                    # empty modules; patch every importer with direct sub-module imports.
-                    # When pname == "inter-hub-models", postUnpack replaces the monolithic
+                    # For inter-hub-lib: same for both hubs (originals still intact in its
-                    # Types.hs → empty stub (not compiled); inter-hub-lib imports TypesPart1-8 directly.
+                    # sourceRoot — each package is unpacked independently).
                     overlays = lib.mkAfter [
                         (final: prev: {
                             ghc = prev.ghc.extend (hfinal: hprev: {
@@ -110,166 +111,48 @@
                                     let drv = hprev.mkDerivation args;
                                     in if (args.pname or "") == "inter-hub-models"
                                        then drv.overrideAttrs (old: {
-                                           # GHC 9.10.3 crash: Data.Binary.Get.runGet at position 287686318.
+                                           # GHC 9.10.3 crash: `module M` re-export syntax in Generated.ActualTypes
-                                           # Invariant regardless of flags. Workaround: split the 476-module
+                                           # embeds 61 full sub-interfaces into ActualTypes.hi (~287 MB), exceeding
-                                           # inter-hub-models into two Cabal library components so GHC runs
+                                           # GHC's 274 MB binary read limit. Fix: stub both hub files to empty
-                                           # two separate --make invocations instead of one giant one.
+                                           # modules (tiny .hi), patch every importer to use direct sub-module
-                                           #
+                                           # imports (same semantics, no embedded sub-interfaces in .hi).
-                                           # models-inner  (~63 modules): Generated.ActualTypes.* + Enums.
-                                           #   Pure type definitions; no inter-hub-models deps.
-                                           # main library (~413 modules): entity ops + Include instances.
-                                           #   Depends on models-inner.
-                                           #
-                                           # Long-term intent: explicit module boundaries reduce build cost,
-                                           # isolate changes, and make diagnostics cheaper across the board.
                                            configureFlags = (old.configureFlags or []) ++ [
                                                "--ghc-option=-O0"
                                                "--ghc-option=-fomit-interface-pragmas"
                                            ];
                                            postUnpack = (old.postUnpack or "") + ''
-                                               _cabal=$(ls "$sourceRoot"/*.cabal | head -1)
+                                               _actual="$sourceRoot/build/Generated/ActualTypes.hs"
-                                               _pname=$(grep '^name:' "$_cabal" | awk '{print $2}')
 
-                                               # Classify exposed-modules into inner vs outer.
+                                               # Collect direct sub-module imports before stubbing the hub
-                                               # Inner: Generated.ActualTypes.X (capital X) and Generated.Enums
+                                               _act_imp=$(mktemp)
-                                               # — these have zero inter-hub-models dependencies.
+                                               awk '/^import Generated\./{print}' "$_actual" > "$_act_imp"
-                                               # Outer: everything else except Generated.Types (empty stub).
-                                               _inner=$(awk '
-                                                   /^    exposed-modules:/{e=1;next}
-                                                   e && /^        /{m=$1;
-                                                       if (m~/^Generated\.ActualTypes\.[A-Z]/||m=="Generated.Enums")
-                                                           print m;
-                                                       next}
-                                                   e{e=0}
-                                               ' "$_cabal")
-                                               _outer=$(awk '
-                                                   /^    exposed-modules:/{e=1;next}
-                                                   e && /^        /{m=$1;
-                                                       if (!(m~/^Generated\.ActualTypes\.[A-Z]/) &&
-                                                           m!="Generated.Enums" && m!="Generated.Types")
-                                                           print m;
-                                                       next}
-                                                   e{e=0}
-                                               ' "$_cabal")
 
-                                               # Rewrite the cabal file with two library stanzas.
+                                               # Stub both re-export hubs → empty modules → tiny .hi files
-                                               # Hard-coded deps/extensions match IHP default.nix template
+                                               printf '%s\n' 'module Generated.ActualTypes () where' > "$_actual"
-                                               # (pinned flake — these won't drift without a flake update).
-                                               cat > "$_cabal" <<CABAL_EOF
-cabal-version: 3.0
-name: $_pname
-version: 0.1.0
-build-type: Simple
-
-library models-inner
-    default-language: GHC2021
-    hs-source-dirs: build
-    build-depends:
-        base
-        , ihp
-        , basic-prelude
-        , text
-        , bytestring
-        , time
-        , uuid
-        , aeson
-        , postgresql-simple
-        , deepseq
-        , data-default
-        , scientific
-        , string-conversions
-        , hasql
-        , hasql-dynamic-statements
-        , hasql-implicits
-        , hasql-mapping
-        , hasql-postgresql-types
-        , hasql-pool
-        , unordered-containers
-        , postgresql-types
-    exposed-modules:
-$(echo "$_inner" | sed 's/^/        /')
-    default-extensions:
-        OverloadedStrings
-        NoImplicitPrelude
-        ImplicitParams
-        TypeSynonymInstances
-        FlexibleInstances
-        FlexibleContexts
-        InstanceSigs
-        MultiParamTypeClasses
-        TypeFamilies
-        DataKinds
-        TypeOperators
-        UndecidableInstances
-        ConstraintKinds
-        StandaloneDeriving
-        DuplicateRecordFields
-        OverloadedLabels
-        OverloadedRecordDot
-    ghc-options: -Wno-unused-imports -Wno-dodgy-imports -Wno-unused-matches
-
-library
-    default-language: GHC2021
-    hs-source-dirs: build
-    build-depends:
-        $_pname:models-inner
-        , base
-        , ihp
-        , basic-prelude
-        , text
-        , bytestring
-        , time
-        , uuid
-        , aeson
-        , postgresql-simple
-        , deepseq
-        , data-default
-        , scientific
-        , string-conversions
-        , hasql
-        , hasql-dynamic-statements
-        , hasql-implicits
-        , hasql-mapping
-        , hasql-postgresql-types
-        , hasql-pool
-        , unordered-containers
-        , postgresql-types
-    exposed-modules:
-$(echo "$_outer" | sed 's/^/        /')
-    default-extensions:
-        OverloadedStrings
-        NoImplicitPrelude
-        ImplicitParams
-        TypeSynonymInstances
-        FlexibleInstances
-        FlexibleContexts
-        InstanceSigs
-        MultiParamTypeClasses
-        TypeFamilies
-        DataKinds
-        TypeOperators
-        UndecidableInstances
-        ConstraintKinds
-        StandaloneDeriving
-        DuplicateRecordFields
-        OverloadedLabels
-        OverloadedRecordDot
-    ghc-options: -Wno-unused-imports -Wno-dodgy-imports -Wno-unused-matches
-CABAL_EOF
-
-                                               # Stub out Generated.Types (kept as file for inter-hub-lib)
                                                printf '%s\n' 'module Generated.Types () where' \
                                                    > "$sourceRoot/build/Generated/Types.hs"
+
+                                               # Patch every entity file that imports the hub → direct imports
+                                               find "$sourceRoot/build" -name "*.hs" | while IFS= read -r _f; do
+                                                   if grep -qE "^import Generated\.ActualTypes$" "$_f"; then
+                                                       awk -v imp="$_act_imp" '
+                                                       /^import Generated\.ActualTypes$/{
+                                                           while ((getline ln < imp) > 0) print ln
+                                                           close(imp)
+                                                           next
+                                                       }
+                                                       { print }' "$_f" > "$_f.new" && mv "$_f.new" "$_f"
+                                                   fi
+                                               done
+                                               rm -f "$_act_imp"
                                            '';
                                        })
                                        else if (args.pname or "") == "inter-hub-lib"
                                        then drv.overrideAttrs (old: {
-                                           # Generated.Types is an empty stub in models — no re-export hub.
+                                           # Both Generated.Types and Generated.ActualTypes are empty stubs in
-                                           # Replace every bare `import Generated.Types` with direct imports
+                                           # models. Replace every bare import with direct sub-module imports,
-                                           # of all 119 individual entity modules (read from the original
+                                           # reading the originals from this package's own sourceRoot (each
-                                           # Generated/Types.hs before it was replaced in models postUnpack —
+                                           # package is unpacked independently, so originals are intact here).
-                                           # each package gets its own unpacked sourceRoot, so Types.hs is
-                                           # still intact here). Individual entity .hi files are ~9 MB each.
                                            postUnpack = (old.postUnpack or "") + ''
                                                _types="$sourceRoot/build/Generated/Types.hs"
                                                _imp=$(mktemp)
@@ -286,6 +169,22 @@ CABAL_EOF
                                                    fi
                                                done
                                                rm -f "$_imp"
+
+                                               _actual="$sourceRoot/build/Generated/ActualTypes.hs"
+                                               _act_imp=$(mktemp)
+                                               awk '/^import Generated\./{print}' "$_actual" > "$_act_imp"
+                                               find "$sourceRoot" -name "*.hs" | while IFS= read -r _f; do
+                                                   if grep -qE "^import Generated\.ActualTypes$" "$_f"; then
+                                                       awk -v imp="$_act_imp" '
+                                                       /^import Generated\.ActualTypes$/{
+                                                           while ((getline ln < imp) > 0) print ln
+                                                           close(imp)
+                                                           next
+                                                       }
+                                                       { print }' "$_f" > "$_f.new" && mv "$_f.new" "$_f"
+                                                   fi
+                                               done
+                                               rm -f "$_act_imp"
                                            '';
                                        })
                                        else drv;