diff --git a/plugins/buildingplan-planner.cpp b/plugins/buildingplan-planner.cpp
index 925d0f4c3..9d73ab4c4 100644
--- a/plugins/buildingplan-planner.cpp
+++ b/plugins/buildingplan-planner.cpp
@@ -12,12 +12,14 @@
 #include "modules/Gui.h"
 #include "modules/Job.h"
 
+#include "LuaTools.h"
 #include "uicommon.h"
 
 #include "buildingplan-planner.h"
 #include "buildingplan-lib.h"
 
 static const std::string planned_building_persistence_key_v1 = "buildingplan/constraints";
+static const std::string planned_building_persistence_key_v2 = "buildingplan/constraints2";
 
 /*
  * ItemFilter
@@ -37,24 +39,24 @@ void ItemFilter::clear()
     materials.clear();
 }
 
-bool ItemFilter::deserialize(PersistentDataItem &config)
+bool ItemFilter::deserialize(std::string ser)
 {
     clear();
 
     std::vector<std::string> tokens;
-    split_string(&tokens, config.val(), "/");
-    if (tokens.size() != 2)
+    split_string(&tokens, ser, "/");
+    if (tokens.size() != 5)
     {
-        debug("invalid ItemFilter serialization: '%s'", config.val().c_str());
+        debug("invalid ItemFilter serialization: '%s'", ser.c_str());
         return false;
     }
 
     if (!deserializeMaterialMask(tokens[0]) || !deserializeMaterials(tokens[1]))
         return false;
 
-    setMinQuality(config.ival(2) - 1);
-    setMaxQuality(config.ival(4) - 1);
-    decorated_only = config.ival(3) - 1;
+    setMinQuality(atoi(tokens[2].c_str()));
+    setMaxQuality(atoi(tokens[3].c_str()));
+    decorated_only = static_cast<bool>(atoi(tokens[4].c_str()));
     return true;
 }
 
@@ -91,7 +93,8 @@ bool ItemFilter::deserializeMaterials(std::string ser)
     return true;
 }
 
-void ItemFilter::serialize(PersistentDataItem &config) const
+// format: mat,mask,elements/materials,list/minq/maxq/decorated
+std::string ItemFilter::serialize() const
 {
     std::ostringstream ser;
     ser << bitfield_to_string(mat_mask, ",") << "/";
@@ -101,10 +104,10 @@ void ItemFilter::serialize(PersistentDataItem &config) const
         for (size_t i = 1; i < materials.size(); ++i)
             ser << "," << materials[i].getToken();
     }
-    config.val() = ser.str();
-    config.ival(2) = min_quality + 1;
-    config.ival(4) = max_quality + 1;
-    config.ival(3) = static_cast<int>(decorated_only) + 1;
+    ser << "/" << static_cast<int>(min_quality);
+    ser << "/" << static_cast<int>(max_quality);
+    ser << "/" << static_cast<int>(decorated_only);
+    return ser.str();
 }
 
 void ItemFilter::clearMaterialMask()
@@ -230,20 +233,59 @@ bool ItemFilter::matches(df::item *item) const
  * PlannedBuilding
  */
 
-static std::vector<ItemFilter> deserializeFilters(PersistentDataItem &config)
+// format: itemfilterser|itemfilterser|...
+static std::string serializeFilters(const std::vector<ItemFilter> &filters)
 {
-    // simplified implementation while we can assume there is only one filter
+    std::ostringstream ser;
+    if (!filters.empty())
+    {
+        ser << filters[0].serialize();
+        for (size_t i = 1; i < filters.size(); ++i)
+            ser << "|" << filters[i].serialize();
+    }
+    return ser.str();
+}
+
+static std::vector<ItemFilter> deserializeFilters(std::string ser)
+{
+    std::vector<std::string> isers;
+    split_string(&isers, ser, "|");
     std::vector<ItemFilter> ret;
-    ItemFilter itemFilter;
-    itemFilter.deserialize(config);
-    ret.push_back(itemFilter);
+    for (auto & iser : isers)
+    {
+        ItemFilter filter;
+        if (filter.deserialize(iser))
+            ret.push_back(filter);
+    }
     return ret;
 }
 
 static size_t getNumFilters(BuildingTypeKey key)
 {
-    // TODO: get num filters in Lua when we handle all building types
-    return 1;
+    auto L = Lua::Core::State;
+    color_ostream_proxy out(Core::getInstance().getConsole());
+    Lua::StackUnwinder top(L);
+
+    if (!lua_checkstack(L, 4) || !Lua::PushModulePublic(
+            out, L, "plugins.buildingplan", "get_num_filters"))
+    {
+        debug("failed to push the lua method on the stack");
+        return 0;
+    }
+
+    Lua::Push(L, std::get<0>(key));
+    Lua::Push(L, std::get<1>(key));
+    Lua::Push(L, std::get<2>(key));
+
+    if (!Lua::SafeCall(out, L, 3, 1))
+    {
+        debug("lua call failed");
+        return 0;
+    }
+
+    int num_filters = lua_tonumber(L, -1);
+    lua_pop(L, 1);
+    return num_filters;
 }
 
 PlannedBuilding::PlannedBuilding(df::building *building, const std::vector<ItemFilter> &filters)
@@ -251,92 +293,27 @@ PlannedBuilding::PlannedBuilding(df::building *building, const std::vector<ItemF
       building_id(building->id),
       filters(filters)
 {
-    config = DFHack::World::AddPersistentData(planned_building_persistence_key_v1);
-    config.ival(1) = building_id;
-    // assume all filter vectors are length 1 for now
-    filters[0].serialize(config);
+    config = DFHack::World::AddPersistentData(planned_building_persistence_key_v2);
+    config.ival(0) = building_id;
+    config.val() = serializeFilters(filters);
 }
 
 PlannedBuilding::PlannedBuilding(PersistentDataItem &config)
     : config(config),
-      building(df::building::find(config.ival(1))),
-      building_id(config.ival(1)),
-      filters(deserializeFilters(config))
-{ }
-
-bool PlannedBuilding::assignClosestItem(std::vector<df::item *> *items_vector)
-{
-    decltype(items_vector->begin()) closest_item;
-    int32_t closest_distance = -1;
-    for (auto item_iter = items_vector->begin(); item_iter != items_vector->end(); item_iter++)
-    {
-        auto item = *item_iter;
-        if (!filters[0].matches(item))
-            continue;
-
-        auto pos = item->pos;
-        auto distance = abs(pos.x - building->centerx) +
-            abs(pos.y - building->centery) +
-            abs(pos.z - building->z) * 50;
-
-        if (closest_distance > -1 && distance >= closest_distance)
-            continue;
-
-        closest_distance = distance;
-        closest_item = item_iter;
-    }
-
-    if (closest_distance > -1 && assignItem(*closest_item))
-    {
-        debug("Item assigned");
-        items_vector->erase(closest_item);
-        remove();
-        return true;
-    }
-
-    return false;
-}
-
-void delete_item_fn(df::job_item *x) { delete x; }
-
-bool PlannedBuilding::assignItem(df::item *item)
+      building(df::building::find(config.ival(0))),
+      building_id(config.ival(0)),
+      filters(deserializeFilters(config.val()))
 {
-    auto ref = df::allocate<df::general_ref_building_holderst>();
-    if (!ref)
-    {
-        Core::printerr("Could not allocate general_ref_building_holderst\n");
-        return false;
-    }
-
-    ref->building_id = building->id;
-
-    if (building->jobs.size() != 1)
-        return false;
-
-    auto job = building->jobs[0];
-
-    for_each_(job->job_items, delete_item_fn);
-    job->job_items.clear();
-    job->flags.bits.suspend = false;
-
-    bool rough = false;
-    Job::attachJobItem(job, item, df::job_item_ref::Hauled);
-    if (item->getType() == item_type::BOULDER)
-        rough = true;
-    building->mat_type = item->getMaterial();
-    building->mat_index = item->getMaterialIndex();
-
-    job->mat_type = building->mat_type;
-    job->mat_index = building->mat_index;
-
-    if (building->needsDesign())
+    if (building)
     {
-        auto act = (df::building_actual *) building;
-        act->design = new df::building_design();
-        act->design->flags.bits.rough = rough;
+        if (filters.size() !=
+            getNumFilters(toBuildingTypeKey(building)))
+        {
+            debug("invalid ItemFilter vector serialization: '%s'",
+                config.val().c_str());
+            building = NULL;
+        }
     }
-
-    return true;
 }
 
 // Ensure the building still exists and is in a valid state. It can disappear
@@ -361,6 +338,8 @@ df::building * PlannedBuilding::getBuilding()
 
 const std::vector<ItemFilter> & PlannedBuilding::getFilters() const
 {
+    // if we want to be able to dynamically change the filters, we'll need to
+    // re-bucket the tasks in Planner.
     return filters;
 }
 
@@ -412,45 +391,112 @@ std::size_t BuildingTypeKeyHash::operator() (const BuildingTypeKey & key) const
  * Planner
  */
 
-void Planner::initialize()
-{
-#define add_building_type(btype, itype) \
-    item_for_building_type[df::building_type::btype] = df::item_type::itype; \
-    available_item_vectors[df::item_type::itype] = std::vector<df::item *>(); \
-    is_relevant_item_type[df::item_type::itype] = true; \
-
-    FOR_ENUM_ITEMS(item_type, it)
-        is_relevant_item_type[it] = false;
-
-    add_building_type(Armorstand, ARMORSTAND);
-    add_building_type(Bed, BED);
-    add_building_type(Chair, CHAIR);
-    add_building_type(Coffin, COFFIN);
-    add_building_type(Door, DOOR);
-    add_building_type(Floodgate, FLOODGATE);
-    add_building_type(Hatch, HATCH_COVER);
-    add_building_type(GrateWall, GRATE);
-    add_building_type(GrateFloor, GRATE);
-    add_building_type(BarsVertical, BAR);
-    add_building_type(BarsFloor, BAR);
-    add_building_type(Cabinet, CABINET);
-    add_building_type(Box, BOX);
-    // skip kennels, farm plot
-    add_building_type(Weaponrack, WEAPONRACK);
-    add_building_type(Statue, STATUE);
-    add_building_type(Slab, SLAB);
-    add_building_type(Table, TABLE);
-    // skip roads ... furnaces
-    add_building_type(WindowGlass, WINDOW);
-    // skip gem window ... support
-    add_building_type(AnimalTrap, ANIMALTRAP);
-    add_building_type(Chain, CHAIN);
-    add_building_type(Cage, CAGE);
-    // skip archery target
-    add_building_type(TractionBench, TRACTION_BENCH);
-    // skip nest box, hive (tools)
-
-#undef add_building_type
+// convert v1 persistent data into v2 format
+// we can remove this conversion code once v2 has been live for a while
+void migrateV1ToV2()
+{
+    std::vector<PersistentDataItem> configs;
+    DFHack::World::GetPersistentData(&configs, planned_building_persistence_key_v1);
+    if (configs.empty())
+        return;
+
+    debug("migrating %zu persisted configs to new format", configs.size());
+    for (auto config : configs)
+    {
+        df::building *bld = df::building::find(config.ival(1));
+        if (!bld)
+        {
+            debug("buliding no longer exists; removing config");
+            DFHack::World::DeletePersistentData(config);
+            continue;
+        }
+
+        if (bld->getBuildStage() != 0 || bld->jobs.size() != 1
+            || bld->jobs[0]->job_items.size() != 1)
+        {
+            debug("building in invalid state; removing config");
+            DFHack::World::DeletePersistentData(config);
+            continue;
+        }
+
+        // fix up the building so we can set the material properties later
+        bld->mat_type = -1;
+        bld->mat_index = -1;
+
+        // the v1 filters are not initialized correctly and will match any item.
+        // we need to fix them up a bit.
+        auto filter = bld->jobs[0]->job_items[0];
+        df::item_type type;
+        switch (bld->getType())
+        {
+        case df::building_type::Armorstand: type = df::item_type::ARMORSTAND; break;
+        case df::building_type::Bed: type = df::item_type::BED; break;
+        case df::building_type::Chair: type = df::item_type::CHAIR; break;
+        case df::building_type::Coffin: type = df::item_type::COFFIN; break;
+        case df::building_type::Door: type = df::item_type::DOOR; break;
+        case df::building_type::Floodgate: type = df::item_type::FLOODGATE; break;
+        case df::building_type::Hatch: type = df::item_type::HATCH_COVER; break;
+        case df::building_type::GrateWall: type = df::item_type::GRATE; break;
+        case df::building_type::GrateFloor: type = df::item_type::GRATE; break;
+        case df::building_type::BarsVertical: type = df::item_type::BAR; break;
+        case df::building_type::BarsFloor: type = df::item_type::BAR; break;
+        case df::building_type::Cabinet: type = df::item_type::CABINET; break;
+        case df::building_type::Box: type = df::item_type::BOX; break;
+        case df::building_type::Weaponrack: type = df::item_type::WEAPONRACK; break;
+        case df::building_type::Statue: type = df::item_type::STATUE; break;
+        case df::building_type::Slab: type = df::item_type::SLAB; break;
+        case df::building_type::Table: type = df::item_type::TABLE; break;
+        case df::building_type::WindowGlass: type = df::item_type::WINDOW; break;
+        case df::building_type::AnimalTrap: type = df::item_type::ANIMALTRAP; break;
+        case df::building_type::Chain: type = df::item_type::CHAIN; break;
+        case df::building_type::Cage: type = df::item_type::CAGE; break;
+        case df::building_type::TractionBench: type = df::item_type::TRACTION_BENCH; break;
+        default:
+            debug("building has unhandled type; removing config");
+            DFHack::World::DeletePersistentData(config);
+            continue;
+        }
+        filter->item_type = type;
+        filter->item_subtype = -1;
+        filter->mat_type = -1;
+        filter->mat_index = -1;
+        filter->flags1.whole = 0;
+        filter->flags2.whole = 0;
+        filter->flags2.bits.allow_artifact = true;
+        filter->flags3.whole = 0;
+        filter->flags4 = 0;
+        filter->flags5 = 0;
+        filter->metal_ore = -1;
+        filter->min_dimension = -1;
+        filter->has_tool_use = df::tool_uses::NONE;
+        filter->quantity = 1;
+
+        std::vector<std::string> tokens;
+        split_string(&tokens, config.val(), "/");
+        if (tokens.size() != 2)
+        {
+            debug("invalid v1 format; removing config");
+            DFHack::World::DeletePersistentData(config);
+            continue;
+        }
+
+        ItemFilter item_filter;
+        item_filter.deserializeMaterialMask(tokens[0]);
+        item_filter.deserializeMaterials(tokens[1]);
+        item_filter.setMinQuality(config.ival(2) - 1);
+        item_filter.setMaxQuality(config.ival(4) - 1);
+        if (config.ival(3) - 1)
+            item_filter.toggleDecoratedOnly();
+
+        // create the v2 record
+        std::vector<ItemFilter> item_filters;
+        item_filters.push_back(item_filter);
+        PlannedBuilding pb(bld, item_filters);
+
+        // remove the v1 record
+        DFHack::World::DeletePersistentData(config);
+        debug("v1 record successfully migrated");
+    }
 }
 
 void Planner::reset()
@@ -458,9 +504,12 @@ void Planner::reset()
     debug("resetting Planner state");
     default_item_filters.clear();
     planned_buildings.clear();
+    tasks.clear();
+
+    migrateV1ToV2();
 
     std::vector<PersistentDataItem> items;
-    DFHack::World::GetPersistentData(&items, planned_building_persistence_key_v1);
+    DFHack::World::GetPersistentData(&items, planned_building_persistence_key_v2);
     debug("found data for %zu planned buildings", items.size());
 
     for (auto i = items.begin(); i != items.end(); i++)
@@ -472,7 +521,8 @@ void Planner::reset()
             continue;
         }
 
-        planned_buildings.push_back(pb);
+        if (registerTasks(pb))
+            planned_buildings.insert(std::make_pair(pb.getBuilding()->id, pb));
     }
 }
 
@@ -487,19 +537,19 @@ void Planner::addPlannedBuilding(df::building *bld)
     }
 
     // protect against multiple registrations
-    if (getPlannedBuilding(bld))
+    if (planned_buildings.count(bld->id) != 0)
     {
-        debug("building already registered");
+        debug("failed to add building: already registered");
         return;
     }
 
     PlannedBuilding pb(bld, item_filters);
-    if (pb.isValid())
+    if (pb.isValid() && registerTasks(pb))
     {
         for (auto job : bld->jobs)
             job->flags.bits.suspend = true;
 
-        planned_buildings.push_back(pb);
+        planned_buildings.insert(std::make_pair(bld->id, pb));
     }
     else
     {
@@ -507,19 +557,107 @@ void Planner::addPlannedBuilding(df::building *bld)
     }
 }
 
-PlannedBuilding * Planner::getPlannedBuilding(df::building *bld)
+static std::string getBucket(const df::job_item & ji,
+                             const std::vector<ItemFilter> & item_filters)
+{
+    std::ostringstream ser;
+
+    // pull out and serialize only known relevant fields. if we miss a few, then
+    // the filter bucket will be slighly less specific than it could be, but
+    // that's probably ok. we'll just end up bucketing slightly different items
+    // together. this is only a problem if the different filter at the front of
+    // the queue doesn't match any available items and blocks filters behind it
+    // that could be matched.
+    ser << ji.item_type << ':' << ji.item_subtype << ':' << ji.mat_type << ':'
+        << ji.mat_index << ':' << ji.flags1.whole << ':' << ji.flags2.whole
+        << ':' << ji.flags3.whole << ':' << ji.flags4 << ':' << ji.flags5 << ':'
+        << ji.metal_ore << ':' << ji.has_tool_use;
+
+    for (auto & item_filter : item_filters)
+    {
+        ser << ':' << item_filter.serialize();
+    }
+
+    return ser.str();
+}
+
+bool Planner::registerTasks(PlannedBuilding & pb)
 {
-    for (auto & pb : planned_buildings)
+    df::building * bld = pb.getBuilding();
+    if (bld->jobs.size() != 1)
+    {
+        debug("unexpected number of jobs: want 1, got %zu", bld->jobs.size());
+        return false;
+    }
+    auto job_items = bld->jobs[0]->job_items;
+    int num_job_items = job_items.size();
+    if (num_job_items < 1)
     {
-        if (pb.getBuilding() == bld)
-            return &pb;
+        debug("unexpected number of job items: want >0, got %d", num_job_items);
+        return false;
     }
-    return NULL;
+    for (int job_item_idx = 0; job_item_idx < num_job_items; ++job_item_idx)
+    {
+        auto vector_id = df::job_item_vector_id::IN_PLAY;
+        auto job_item = job_items[job_item_idx];
+        if (job_item->vector_id)
+          vector_id = job_item->vector_id;
+        auto bucket = getBucket(*job_item, pb.getFilters());
+        for (int item_num = 0; item_num < job_item->quantity; ++item_num)
+        {
+            int32_t id = bld->id;
+            tasks[vector_id][bucket].push(std::make_pair(id, job_item_idx));
+            debug("added task: %s/%s/%d,%d; "
+                  "%zu vectors, %zu buckets, %zu tasks in bucket",
+                  ENUM_KEY_STR(job_item_vector_id, vector_id).c_str(),
+                  bucket.c_str(), id, job_item_idx, tasks.size(),
+                  tasks[vector_id].size(), tasks[vector_id][bucket].size());
+        }
+    }
+    return true;
+}
+
+PlannedBuilding * Planner::getPlannedBuilding(df::building *bld)
+{
+    if (!bld || planned_buildings.count(bld->id) == 0)
+        return NULL;
+    return &planned_buildings.at(bld->id);
 }
 
 bool Planner::isPlannableBuilding(BuildingTypeKey key)
 {
-    return item_for_building_type.count(std::get<0>(key)) > 0;
+    if (getNumFilters(key) == 0)
+        return false;
+
+    // restrict supported types to be the same as the previous implementation
+    switch(std::get<0>(key))
+    {
+        case df::enums::building_type::Armorstand:
+        case df::enums::building_type::Bed:
+        case df::enums::building_type::Chair:
+        case df::enums::building_type::Coffin:
+        case df::enums::building_type::Door:
+        case df::enums::building_type::Floodgate:
+        case df::enums::building_type::Hatch:
+        case df::enums::building_type::GrateWall:
+        case df::enums::building_type::GrateFloor:
+        case df::enums::building_type::BarsVertical:
+        case df::enums::building_type::BarsFloor:
+        case df::enums::building_type::Cabinet:
+        case df::enums::building_type::Box:
+        case df::enums::building_type::Weaponrack:
+        case df::enums::building_type::Statue:
+        case df::enums::building_type::Slab:
+        case df::enums::building_type::Table:
+        case df::enums::building_type::WindowGlass:
+        case df::enums::building_type::AnimalTrap:
+        case df::enums::building_type::Chain:
+        case df::enums::building_type::Cage:
+        case df::enums::building_type::TractionBench:
+            return true;
+        default:
+            return false;
+    }
 }
 
 Planner::ItemFiltersWrapper Planner::getItemFilters(BuildingTypeKey key)
@@ -535,84 +673,257 @@ Planner::ItemFiltersWrapper Planner::getItemFilters(BuildingTypeKey key)
     return ItemFiltersWrapper(default_item_filters[key]);
 }
 
-void Planner::doCycle()
+// precompute a bitmask with bad item flags
+struct BadFlags
 {
-    debug("Running Cycle");
-    if (planned_buildings.size() == 0)
-        return;
-
-    debug("Planned count: %zu", planned_buildings.size());
+    uint32_t whole;
 
-    gather_available_items();
-    for (auto building_iter = planned_buildings.begin(); building_iter != planned_buildings.end();)
+    BadFlags()
     {
-        if (building_iter->isValid())
-        {
-            auto type = building_iter->getBuilding()->getType();
-            debug("Trying to allocate %s", enum_item_key_str(type));
+        df::item_flags flags;
+        #define F(x) flags.bits.x = true;
+        F(dump); F(forbid); F(garbage_collect);
+        F(hostile); F(on_fire); F(rotten); F(trader);
+        F(in_building); F(construction); F(in_job);
+        F(owned); F(in_chest); F(removed); F(encased);
+        #undef F
+        whole = flags.whole;
+    }
+};
 
-            auto required_item_type = item_for_building_type[type];
-            auto items_vector = &available_item_vectors[required_item_type];
-            if (items_vector->size() == 0 || !building_iter->assignClosestItem(items_vector))
-            {
-                debug("Unable to allocate an item");
-                ++building_iter;
-                continue;
-            }
-        }
-        debug("Removing building plan");
-        building_iter->remove();
-        building_iter = planned_buildings.erase(building_iter);
+static bool itemPassesScreen(df::item * item)
+{
+    static BadFlags bad_flags;
+    return !(item->flags.whole & bad_flags.whole)
+        && !item->isAssignedToStockpile()
+        // TODO: make this configurable
+        && !(item->getType() == df::item_type::BOX && item->isBag());
+}
+
+static bool matchesFilters(df::item * item,
+                           df::job_item * job_item,
+                           const ItemFilter & item_filter)
+{
+    // check the properties that are not checked by Job::isSuitableItem()
+    if (job_item->item_type > -1 && job_item->item_type != item->getType())
+        return false;
+
+    if (job_item->item_subtype > -1 &&
+        job_item->item_subtype != item->getSubtype())
+        return false;
+
+    if (job_item->flags2.bits.building_material && !item->isBuildMat())
+        return false;
+
+    if (job_item->metal_ore > -1 && !item->isMetalOre(job_item->metal_ore))
+        return false;
+
+    if (job_item->has_tool_use > df::tool_uses::NONE
+        && !item->hasToolUse(job_item->has_tool_use))
+        return false;
+
+    return DFHack::Job::isSuitableItem(
+            job_item, item->getType(), item->getSubtype())
+        && DFHack::Job::isSuitableMaterial(
+            job_item, item->getMaterial(), item->getMaterialIndex())
+        && item_filter.matches(item);
+}
+
+// note that this just removes the PlannedBuilding. the tasks will get dropped
+// as we discover them in the tasks queues and they fail their isValid() check.
+// this "lazy" task cleaning algorithm works because there is no way to
+// re-register a building once it has been removed -- if it fails isValid()
+// then it has either been built or desroyed. therefore there is no chance of
+// duplicate tasks getting added to the tasks queues.
+void Planner::unregisterBuilding(int32_t id)
+{
+    if (planned_buildings.count(id) > 0)
+    {
+        planned_buildings.at(id).remove();
+        planned_buildings.erase(id);
     }
 }
 
-void Planner::gather_available_items()
+static bool isJobReady(df::job * job)
 {
-    debug("Gather available items");
-    for (auto iter = available_item_vectors.begin(); iter != available_item_vectors.end(); iter++)
+    int needed_items = 0;
+    for (auto job_item : job->job_items) { needed_items += job_item->quantity; }
+    if (needed_items)
     {
-        iter->second.clear();
+        debug("building needs %d more item(s)", needed_items);
+        return false;
     }
+    return true;
+}
 
-    // Precompute a bitmask with the bad flags
-    df::item_flags bad_flags;
-    bad_flags.whole = 0;
+static bool job_item_idx_lt(df::job_item_ref *a, df::job_item_ref *b)
+{
+    // we want the items in the opposite order of the filters
+    return a->job_item_idx > b->job_item_idx;
+}
 
-    #define F(x) bad_flags.bits.x = true;
-    F(dump); F(forbid); F(garbage_collect);
-    F(hostile); F(on_fire); F(rotten); F(trader);
-    F(in_building); F(construction); F(artifact);
-    #undef F
+// this function does not remove the job_items since their quantity fields are
+// now all at 0, so there is no risk of having extra items attached. we don't
+// remove them to keep the "finalize with buildingplan active" path as similar
+// as possible to the "finalize with buildingplan disabled" path.
+static void finalizeBuilding(df::building * bld)
+{
+    debug("finalizing building %d", bld->id);
+    auto job = bld->jobs[0];
 
-    std::vector<df::item*> &items = df::global::world->items.other[df::items_other_id::IN_PLAY];
+    // sort the items so they get added to the structure in the correct order
+    std::sort(job->items.begin(), job->items.end(), job_item_idx_lt);
 
-    for (size_t i = 0; i < items.size(); i++)
+    // derive the material properties of the building and job from the first
+    // applicable item, though if any boulders are involved, it makes the whole
+    // structure "rough".
+    bool rough = false;
+    for (auto attached_item : job->items)
     {
-        df::item *item = items[i];
-
-        if (item->flags.whole & bad_flags.whole)
-            continue;
-
-        df::item_type itype = item->getType();
-        if (!is_relevant_item_type[itype])
-            continue;
+        df::item *item = attached_item->item;
+        rough = rough || item->getType() == item_type::BOULDER;
+        if (bld->mat_type == -1)
+        {
+            bld->mat_type = item->getMaterial();
+            job->mat_type = bld->mat_type;
+        }
+        if (bld->mat_index == -1)
+        {
+            bld->mat_index = item->getMaterialIndex();
+            job->mat_index = bld->mat_index;
+        }
+    }
 
-        if (itype == df::item_type::BOX && item->isBag())
-            continue; //Skip bags
+    if (bld->needsDesign())
+    {
+        auto act = (df::building_actual *)bld;
+        if (!act->design)
+            act->design = new df::building_design();
+        act->design->flags.bits.rough = rough;
+    }
 
-        if (item->flags.bits.artifact)
-            continue;
+    // we're good to go!
+    job->flags.bits.suspend = false;
+    Job::checkBuildingsNow();
+}
 
-        if (item->flags.bits.in_job ||
-            item->isAssignedToStockpile() ||
-            item->flags.bits.owned ||
-            item->flags.bits.in_chest)
+void Planner::popInvalidTasks(std::queue<std::pair<int32_t, int>> & task_queue)
+{
+    while (!task_queue.empty())
+    {
+        auto & task = task_queue.front();
+        auto id = task.first;
+        if (planned_buildings.count(id) > 0)
         {
-            continue;
+            PlannedBuilding & pb = planned_buildings.at(id);
+            if (pb.isValid() &&
+                pb.getBuilding()->jobs[0]->job_items[task.second]->quantity)
+            {
+                break;
+            }
         }
+        debug("discarding invalid task: bld=%d, job_item_idx=%d",
+              id, task.second);
+        task_queue.pop();
+        unregisterBuilding(id);
+    }
+}
 
-        available_item_vectors[itype].push_back(item);
+void Planner::doCycle()
+{
+    debug("running cycle for %zu registered buildings",
+          planned_buildings.size());
+    for (auto it = tasks.begin(); it != tasks.end();)
+    {
+        auto & buckets = it->second;
+        auto other_id = ENUM_ATTR(job_item_vector_id, other, it->first);
+        auto item_vector = df::global::world->items.other[other_id];
+        debug("matching %zu items in vector %s against %zu buckets",
+              item_vector.size(),
+              ENUM_KEY_STR(job_item_vector_id, it->first).c_str(),
+              buckets.size());
+        for (auto item_it = item_vector.rbegin();
+             item_it != item_vector.rend();
+             ++item_it)
+        {
+            auto item = *item_it;
+            if (!itemPassesScreen(item))
+                continue;
+            for (auto bucket_it = buckets.begin(); bucket_it != buckets.end();)
+            {
+                auto & task_queue = bucket_it->second;
+                popInvalidTasks(task_queue);
+                if (task_queue.empty())
+                {
+                    debug("removing empty bucket: %s/%s; %zu buckets left",
+                          ENUM_KEY_STR(job_item_vector_id, it->first).c_str(),
+                          bucket_it->first.c_str(),
+                          buckets.size() - 1);
+                    bucket_it = buckets.erase(bucket_it);
+                    continue;
+                }
+                auto & task = task_queue.front();
+                auto id = task.first;
+                auto & pb = planned_buildings.at(id);
+                auto building = pb.getBuilding();
+                auto job = building->jobs[0];
+                auto filter_idx = task.second;
+                if (matchesFilters(item, job->job_items[filter_idx],
+                        pb.getFilters()[filter_idx])
+                   && DFHack::Job::attachJobItem(job, item,
+                            df::job_item_ref::Hauled, filter_idx))
+                {
+                    MaterialInfo material;
+                    material.decode(item);
+                    ItemTypeInfo item_type;
+                    item_type.decode(item);
+                    debug("attached %s %s to filter %d for %s(%d): %s/%s",
+                          material.toString().c_str(),
+                          item_type.toString().c_str(),
+                          filter_idx,
+                          ENUM_KEY_STR(building_type, building->getType()).c_str(),
+                          id,
+                          ENUM_KEY_STR(job_item_vector_id, it->first).c_str(),
+                          bucket_it->first.c_str());
+                    // keep quantity aligned with the actual number of remaining
+                    // items so if buildingplan is turned off, the building will
+                    // be completed with the correct number of items.
+                    --job->job_items[filter_idx]->quantity;
+                    task_queue.pop();
+                    if (isJobReady(job))
+                    {
+                        finalizeBuilding(building);
+                        unregisterBuilding(id);
+                    }
+                    if (task_queue.empty())
+                    {
+                        debug(
+                            "removing empty item bucket: %s/%s; %zu remaining",
+                            ENUM_KEY_STR(job_item_vector_id, it->first).c_str(),
+                            bucket_it->first.c_str(),
+                            buckets.size() - 1);
+                        buckets.erase(bucket_it);
+                    }
+                    // we found a home for this item; no need to look further
+                    break;
+                }
+                ++bucket_it;
+            }
+            if (buckets.empty())
+                break;
+        }
+        if (buckets.empty())
+        {
+            debug("removing empty vector: %s; %zu vectors left",
+                  ENUM_KEY_STR(job_item_vector_id, it->first).c_str(),
+                  tasks.size() - 1);
+            it = tasks.erase(it);
+        }
+        else
+            ++it;
     }
+    debug("cycle done; %zu registered buildings left",
+          planned_buildings.size());
 }
 
 Planner planner;
diff --git a/plugins/buildingplan-planner.h b/plugins/buildingplan-planner.h
index cda217d81..22d0487c3 100644
--- a/plugins/buildingplan-planner.h
+++ b/plugins/buildingplan-planner.h
@@ -1,5 +1,6 @@
 #pragma once
 
+#include <queue>
 #include <unordered_map>
 
 #include "df/building.h"
@@ -16,8 +17,8 @@ public:
     ItemFilter();
 
     void clear();
-    bool deserialize(DFHack::PersistentDataItem &config);
-    void serialize(DFHack::PersistentDataItem &config) const;
+    bool deserialize(std::string ser);
+    std::string serialize() const;
 
     void addMaterialMask(uint32_t mask);
     void clearMaterialMask();
@@ -40,6 +41,9 @@ public:
     bool matches(df::item *item) const;
 
 private:
+    // remove friend declaration when we no longer need v1 deserialization
+    friend void migrateV1ToV2();
+
     df::dfhack_material_category mat_mask;
     std::vector<DFHack::MaterialInfo> materials;
     df::item_quality min_quality;
@@ -59,9 +63,6 @@ public:
     PlannedBuilding(df::building *building, const std::vector<ItemFilter> &filters);
     PlannedBuilding(DFHack::PersistentDataItem &config);
 
-    bool assignClosestItem(std::vector<df::item *> *items_vector);
-    bool assignItem(df::item *item);
-
     bool isValid() const;
     void remove();
 
@@ -71,8 +72,8 @@ public:
 private:
     DFHack::PersistentDataItem config;
     df::building *building;
-    df::building::key_field_type building_id;
-    std::vector<ItemFilter> filters;
+    const df::building::key_field_type building_id;
+    const std::vector<ItemFilter> filters;
 };
 
 // building type, subtype, custom
@@ -103,7 +104,6 @@ public:
         std::vector<ItemFilter> &item_filters;
     };
 
-    void initialize();
     void reset();
 
     void addPlannedBuilding(df::building *bld);
@@ -117,15 +117,17 @@ public:
     void doCycle();
 
 private:
-    std::map<df::building_type, df::item_type> item_for_building_type;
     std::unordered_map<BuildingTypeKey,
                        std::vector<ItemFilter>,
                        BuildingTypeKeyHash> default_item_filters;
-    std::map<df::item_type, std::vector<df::item *>> available_item_vectors;
-    std::map<df::item_type, bool> is_relevant_item_type; //Needed for fast check when looping over all items
-    std::vector<PlannedBuilding> planned_buildings;
-
-    void gather_available_items();
+    // building id -> PlannedBuilding
+    std::unordered_map<int32_t, PlannedBuilding> planned_buildings;
+    // vector id -> filter bucket -> queue of (building id, job_item index)
+    std::map<df::job_item_vector_id, std::map<std::string, std::queue<std::pair<int32_t, int>>>> tasks;
+
+    bool registerTasks(PlannedBuilding &plannedBuilding);
+    void unregisterBuilding(int32_t id);
+    void popInvalidTasks(std::queue<std::pair<int32_t, int>> &task_queue);
 };
 
 extern Planner planner;
diff --git a/plugins/buildingplan.cpp b/plugins/buildingplan.cpp
index 3390b04b0..74fe4b497 100644
--- a/plugins/buildingplan.cpp
+++ b/plugins/buildingplan.cpp
@@ -1,5 +1,3 @@
-#include <unordered_map>
-
 #include "df/entity_position.h"
 #include "df/interface_key.h"
 #include "df/ui_build_selector.h"
@@ -17,7 +15,7 @@
 #include "buildingplan-lib.h"
 
 DFHACK_PLUGIN("buildingplan");
-#define PLUGIN_VERSION 0.15
+#define PLUGIN_VERSION 2.0
 REQUIRE_GLOBAL(ui);
 REQUIRE_GLOBAL(ui_build_selector);
 REQUIRE_GLOBAL(world);
@@ -287,6 +285,33 @@ static bool is_planmode_enabled(BuildingTypeKey key)
     return planmode_enabled[key] || quickfort_mode;
 }
 
+static std::string get_item_label(const BuildingTypeKey &key, int item_idx)
+{
+     auto L = Lua::Core::State;
+     color_ostream_proxy out(Core::getInstance().getConsole());
+     Lua::StackUnwinder top(L);
+
+    if (!lua_checkstack(L, 5) ||
+        !Lua::PushModulePublic(
+            out, L, "plugins.buildingplan", "get_item_label"))
+        return "Failed push";
+
+    Lua::Push(L, std::get<0>(key));
+    Lua::Push(L, std::get<1>(key));
+    Lua::Push(L, std::get<2>(key));
+    Lua::Push(L, item_idx);
+
+    if (!Lua::SafeCall(out, L, 4, 1))
+        return "Failed call";
+
+    const char *s = lua_tostring(L, -1);
+    if (!s)
+        return "No string";
+
+    lua_pop(L, 1);
+    return s;
+}
+
 static bool construct_planned_building()
 {
      auto L = Lua::Core::State;
@@ -321,6 +346,16 @@ struct buildingplan_query_hook : public df::viewscreen_dwarfmodest
 {
     typedef df::viewscreen_dwarfmodest interpose_base;
 
+    // no non-static fields allowed (according to VTableInterpose.h)
+    static df::building *bld;
+    static PlannedBuilding *pb;
+    static int filter_count;
+    static int filter_idx;
+
+    // logic is reversed since we're starting at the last filter
+    bool hasNextFilter() const { return filter_idx > 0; }
+    bool hasPrevFilter() const { return filter_idx + 1 < filter_count; }
+
     bool isInPlannedBuildingQueryMode()
     {
         return (ui->main.mode == df::ui_sidebar_mode::QueryBuilding ||
@@ -328,21 +363,45 @@ struct buildingplan_query_hook : public df::viewscreen_dwarfmodest
             planner.getPlannedBuilding(world->selected_building);
     }
 
+    // reinit static fields when selected building changes
+    void initStatics()
+    {
+        df::building *cur_bld = world->selected_building;
+        if (bld != cur_bld)
+        {
+            bld = cur_bld;
+            pb = planner.getPlannedBuilding(bld);
+            filter_count = pb->getFilters().size();
+            filter_idx = filter_count - 1;
+        }
+    }
+
     bool handleInput(set<df::interface_key> *input)
     {
         if (!isInPlannedBuildingQueryMode())
             return false;
 
+        initStatics();
+
         if (input->count(interface_key::SUSPENDBUILDING))
             return true; // Don't unsuspend planned buildings
         if (input->count(interface_key::DESTROYBUILDING))
         {
-            // remove persistent data and allow the parent to handle the key
-            // so the building is removed
-            planner.getPlannedBuilding(world->selected_building)->remove();
+            // remove persistent data
+            pb->remove();
+            // still allow the building to be removed
+            return false;
         }
 
-        return false;
+        // ctrl+Right
+        if (input->count(interface_key::A_MOVE_E_DOWN) && hasNextFilter())
+            --filter_idx;
+        // ctrl+Left
+        else if (input->count(interface_key::A_MOVE_W_DOWN) && hasPrevFilter())
+            ++filter_idx;
+        else
+            return false;
+        return true;
     }
 
     DEFINE_VMETHOD_INTERPOSE(void, feed, (set<df::interface_key> *input))
@@ -358,6 +417,8 @@ struct buildingplan_query_hook : public df::viewscreen_dwarfmodest
         if (!isInPlannedBuildingQueryMode())
             return;
 
+        initStatics();
+
         // Hide suspend toggle option
         auto dims = Gui::getDwarfmodeViewDims();
         int left_margin = dims.menu_x1 + 1;
@@ -366,10 +427,13 @@ struct buildingplan_query_hook : public df::viewscreen_dwarfmodest
         Screen::Pen pen(' ', COLOR_BLACK);
         Screen::fillRect(pen, x, y, dims.menu_x2, y);
 
-        // all current buildings only have one filter
-        auto & filter = planner.getPlannedBuilding(world->selected_building)->getFilters()[0];
+        auto & filter = pb->getFilters()[filter_idx];
         y = 24;
-        OutputString(COLOR_WHITE, x, y, "Planned Building Filter", true, left_margin);
+        std::string item_label =
+            stl_sprintf("Item %d of %d", filter_count - filter_idx, filter_count);
+        OutputString(COLOR_WHITE, x, y, "Planned Building Filter", true, left_margin + 1);
+        OutputString(COLOR_WHITE, x, y, item_label.c_str(), true, left_margin + 1);
+        OutputString(COLOR_WHITE, x, y, get_item_label(toBuildingTypeKey(bld), filter_idx).c_str(), true, left_margin);
         ++y;
         OutputString(COLOR_BROWN, x, y, "Min Quality: ", false, left_margin);
         OutputString(COLOR_BLUE, x, y, filter.getMinQuality(), true, left_margin);
@@ -383,13 +447,35 @@ struct buildingplan_query_hook : public df::viewscreen_dwarfmodest
         auto filters = filter.getMaterials();
         for (auto it = filters.begin(); it != filters.end(); ++it)
             OutputString(COLOR_BLUE, x, y, "*" + *it, true, left_margin);
+
+        ++y;
+        if (hasPrevFilter())
+            OutputHotkeyString(x, y, "Prev Item", "Ctrl+Left", true, left_margin);
+        if (hasNextFilter())
+            OutputHotkeyString(x, y, "Next Item", "Ctrl+Right", true, left_margin);
     }
 };
 
+df::building * buildingplan_query_hook::bld;
+PlannedBuilding * buildingplan_query_hook::pb;
+int buildingplan_query_hook::filter_count;
+int buildingplan_query_hook::filter_idx;
+
 struct buildingplan_place_hook : public df::viewscreen_dwarfmodest
 {
     typedef df::viewscreen_dwarfmodest interpose_base;
 
+    // no non-static fields allowed (according to VTableInterpose.h)
+    static BuildingTypeKey key;
+    static std::vector<ItemFilter>::reverse_iterator filter_rbegin;
+    static std::vector<ItemFilter>::reverse_iterator filter_rend;
+    static std::vector<ItemFilter>::reverse_iterator filter;
+    static int filter_count;
+    static int filter_idx;
+
+    bool hasNextFilter() const { return filter + 1 != filter_rend; }
+    bool hasPrevFilter() const { return filter != filter_rbegin; }
+
     bool isInPlannedBuildingPlacementMode()
     {
         return ui->main.mode == ui_sidebar_mode::Build &&
@@ -398,6 +484,22 @@ struct buildingplan_place_hook : public df::viewscreen_dwarfmodest
             planner.isPlannableBuilding(toBuildingTypeKey(ui_build_selector));
     }
 
+    // reinit static fields when selected building type changes
+    void initStatics()
+    {
+        BuildingTypeKey cur_key = toBuildingTypeKey(ui_build_selector);
+        if (key != cur_key)
+        {
+            key = cur_key;
+            auto wrapper = planner.getItemFilters(key);
+            filter_rbegin = wrapper.rbegin();
+            filter_rend = wrapper.rend();
+            filter = filter_rbegin;
+            filter_count = wrapper.get().size();
+            filter_idx = filter_count - 1;
+        }
+    }
+
     bool handleInput(set<df::interface_key> *input)
     {
         if (!isInPlannedBuildingPlacementMode())
@@ -405,6 +507,8 @@ struct buildingplan_place_hook : public df::viewscreen_dwarfmodest
             show_help = false;
             return false;
         }
+        
+        initStatics();
 
         if (in_dummy_screen)
         {
@@ -428,7 +532,6 @@ struct buildingplan_place_hook : public df::viewscreen_dwarfmodest
             show_help = true;
         }
 
-        BuildingTypeKey key = toBuildingTypeKey(ui_build_selector);
         if (input->count(interface_key::CUSTOM_SHIFT_P))
         {
             planmode_enabled[key] = !planmode_enabled[key];
@@ -456,8 +559,6 @@ struct buildingplan_place_hook : public df::viewscreen_dwarfmodest
             return true;
         }
 
-        // all current buildings only have one filter
-        auto filter = planner.getItemFilters(key).rbegin();
         if (input->count(interface_key::CUSTOM_SHIFT_M))
             Screen::show(dts::make_unique<ViewscreenChooseMaterial>(*filter), plugin_self);
         else if (input->count(interface_key::CUSTOM_Q))
@@ -470,6 +571,18 @@ struct buildingplan_place_hook : public df::viewscreen_dwarfmodest
             filter->incMaxQuality();
         else if (input->count(interface_key::CUSTOM_SHIFT_D))
             filter->toggleDecoratedOnly();
+        // ctrl+Right
+        else if (input->count(interface_key::A_MOVE_E_DOWN) && hasNextFilter())
+        {
+            ++filter;
+            --filter_idx;
+        }
+        // ctrl+Left
+        else if (input->count(interface_key::A_MOVE_W_DOWN) && hasPrevFilter())
+        {
+            --filter;
+            ++filter_idx;
+        }
         else
             return false;
         return true;
@@ -484,7 +597,6 @@ struct buildingplan_place_hook : public df::viewscreen_dwarfmodest
     DEFINE_VMETHOD_INTERPOSE(void, render, ())
     {
         bool plannable = isInPlannedBuildingPlacementMode();
-        BuildingTypeKey key = toBuildingTypeKey(ui_build_selector);
         if (plannable && is_planmode_enabled(key))
         {
             if (ui_build_selector->stage < 1)
@@ -509,6 +621,8 @@ struct buildingplan_place_hook : public df::viewscreen_dwarfmodest
         if (!plannable)
             return;
 
+        initStatics();
+
         auto dims = Gui::getDwarfmodeViewDims();
         int left_margin = dims.menu_x1 + 1;
         int x = left_margin;
@@ -542,8 +656,13 @@ struct buildingplan_place_hook : public df::viewscreen_dwarfmodest
         if (!is_planmode_enabled(key))
             return;
 
-        auto filter = planner.getItemFilters(key).rbegin();
         y += 2;
+        std::string title =
+            stl_sprintf("Filter for Item %d of %d:",
+                        filter_count - filter_idx, filter_count);
+        OutputString(COLOR_WHITE, x, y, title.c_str(), true, left_margin + 1);
+        OutputString(COLOR_WHITE, x, y, get_item_label(key, filter_idx).c_str(), true, left_margin);
+
         OutputHotkeyString(x, y, "Min Quality: ", "qw");
         OutputString(COLOR_BROWN, x, y, filter->getMinQuality(), true, left_margin);
 
@@ -557,9 +676,22 @@ struct buildingplan_place_hook : public df::viewscreen_dwarfmodest
         for (auto it = filter_descriptions.begin();
              it != filter_descriptions.end(); ++it)
              OutputString(COLOR_BROWN, x, y, "   *" + *it, true, left_margin);
+
+        y += 2;
+        if (hasPrevFilter())
+            OutputHotkeyString(x, y, "Prev Item", "Ctrl+Left", true, left_margin);
+        if (hasNextFilter())
+            OutputHotkeyString(x, y, "Next Item", "Ctrl+Right", true, left_margin);
     }
 };
 
+BuildingTypeKey buildingplan_place_hook::key;
+std::vector<ItemFilter>::reverse_iterator buildingplan_place_hook::filter_rbegin;
+std::vector<ItemFilter>::reverse_iterator buildingplan_place_hook::filter_rend;
+std::vector<ItemFilter>::reverse_iterator buildingplan_place_hook::filter;
+int buildingplan_place_hook::filter_count;
+int buildingplan_place_hook::filter_idx;
+
 struct buildingplan_room_hook : public df::viewscreen_dwarfmodest
 {
     typedef df::viewscreen_dwarfmodest interpose_base;
@@ -704,7 +836,6 @@ DFhackCExport command_result plugin_init ( color_ostream &out, std::vector <Plug
         PluginCommand(
         "buildingplan", "Plan building construction before you have materials",
         buildingplan_cmd, false, "Run 'buildingplan debug [on|off]' to toggle debugging, or 'buildingplan version' to query the plugin version."));
-    planner.initialize();
 
     return CR_OK;
 }
diff --git a/plugins/fortplan.cpp b/plugins/fortplan.cpp
index 8b8dc5584..3eca32c50 100644
--- a/plugins/fortplan.cpp
+++ b/plugins/fortplan.cpp
@@ -132,8 +132,6 @@ DFhackCExport command_result plugin_init ( color_ostream &out, vector <PluginCom
     buildings.push_back(BuildingInfo("N",df::building_type::NestBox,"Nest Box",1,1));
     buildings.push_back(BuildingInfo("~h",df::building_type::Hive,"Hive",1,1));
 
-    planner.initialize();
-
     return CR_OK;
 }
 
diff --git a/plugins/lua/buildingplan.lua b/plugins/lua/buildingplan.lua
index 1ab462201..49b80990f 100644
--- a/plugins/lua/buildingplan.lua
+++ b/plugins/lua/buildingplan.lua
@@ -14,6 +14,53 @@ local _ENV = mkmodule('plugins.buildingplan')
 local guidm = require('gui.dwarfmode')
 require('dfhack.buildings')
 
+-- does not need the core suspended
+function get_num_filters(btype, subtype, custom)
+    local filters = dfhack.buildings.getFiltersByType(
+        {}, btype, subtype, custom)
+    if filters then return #filters end
+    return 0
+end
+
+local function to_title_case(str)
+    str = str:gsub('(%a)([%w_]*)',
+        function (first, rest) return first:upper()..rest:lower() end)
+    str = str:gsub('_', ' ')
+    return str
+end
+
+-- returns a reasonable label for the item based on the qualities of the filter
+-- does not need the core suspended
+-- reverse_idx is 0-based and is expected to be counted from the *last* filter
+function get_item_label(btype, subtype, custom, reverse_idx)
+    local filters = dfhack.buildings.getFiltersByType(
+        {}, btype, subtype, custom)
+    if not filters then return 'No item' end
+    if reverse_idx < 0 or reverse_idx >= #filters then
+        return 'Invalid index'
+    end
+    local filter = filters[#filters-reverse_idx]
+    if filter.has_tool_use then
+        return to_title_case(df.tool_uses[filter.has_tool_use])
+    end
+    if filter.item_type then
+        return to_title_case(df.item_type[filter.item_type])
+    end
+    if filter.flags2 and filter.flags2.building_material then
+        if filter.flags2.fire_safe then
+            return "Fire-safe building material";
+        end
+        if filter.flags2.magma_safe then
+            return "Magma-safe building material";
+        end
+        return "Generic building material";
+    end
+    if filter.vector_id then
+        return to_title_case(df.job_item_vector_id[filter.vector_id])
+    end
+    return "Unknown";
+end
+
 -- needs the core suspended
 function construct_building_from_ui_state()
     local uibs = df.global.ui_build_selector