diff --git a/abstutil/src/lib.rs b/abstutil/src/lib.rs
index 6406d814ba..214ce64aea 100644
--- a/abstutil/src/lib.rs
+++ b/abstutil/src/lib.rs
@@ -5,14 +5,6 @@
 // - A/B Street-specific filesystem paths
 // - true utility functions (collections, prettyprinting, CLI parsing
 
-mod abst_paths;
-mod cli;
-mod collections;
-mod io;
-mod serde;
-mod time;
-mod utils;
-
 #[macro_use]
 extern crate log;
 
@@ -33,4 +25,10 @@ pub use collections::*;
 pub use time::*;
 pub use utils::*;
 
+mod cli;
+mod collections;
+mod io;
+mod random;
+mod time;
+
 const PROGRESS_FREQUENCY_SECONDS: f64 = 0.2;
diff --git a/convert_osm/src/lib.rs b/convert_osm/src/lib.rs
index 36a6d76d28..be77974ef8 100644
--- a/convert_osm/src/lib.rs
+++ b/convert_osm/src/lib.rs
@@ -1,3 +1,8 @@
+use abstutil::Timer;
+use geom::{Distance, FindClosest, GPSBounds, LonLat, Pt2D, Ring};
+use map_model::raw::RawMap;
+use map_model::{osm, MapConfig, NamePerLanguage};
+
 mod clip;
 mod extract;
 mod parking;
@@ -7,11 +12,6 @@ mod split_ways;
 mod srtm;
 mod transit;
 
-use abstutil::Timer;
-use geom::{Distance, FindClosest, GPSBounds, LonLat, Pt2D, Ring};
-use map_model::raw::RawMap;
-use map_model::{osm, MapConfig, NamePerLanguage};
-
 pub struct Options {
     pub osm_input: String,
     pub city_name: String,
diff --git a/game/src/common/mod.rs b/game/src/common/mod.rs
index 1d1eef8bd6..16b9c14612 100644
--- a/game/src/common/mod.rs
+++ b/game/src/common/mod.rs
@@ -1,11 +1,3 @@
-mod city_picker;
-mod colors;
-mod heatmap;
-mod isochrone;
-mod minimap;
-mod navigate;
-mod warp;
-
 pub use self::city_picker::CityPicker;
 pub use self::colors::{ColorDiscrete, ColorLegend, ColorNetwork, ColorScale, DivergingScale};
 pub use self::heatmap::{make_heatmap, HeatmapOptions};
@@ -24,6 +16,14 @@ use widgetry::{
     ScreenDims, ScreenPt, ScreenRectangle, Text, VerticalAlignment, Widget,
 };
 
+mod city_picker;
+mod colors;
+mod heatmap;
+mod isochrone;
+mod minimap;
+mod navigate;
+mod warp;
+
 // TODO This is now just used in two modes...
 pub struct CommonState {
     // TODO Better to express these as mutex
diff --git a/game/src/debug/mod.rs b/game/src/debug/mod.rs
index f172d10c1d..713d8829db 100644
--- a/game/src/debug/mod.rs
+++ b/game/src/debug/mod.rs
@@ -1,9 +1,3 @@
-mod floodfill;
-mod objects;
-pub mod path_counter;
-mod polygons;
-pub mod shared_row;
-
 use crate::app::{App, ShowLayers, ShowObject};
 use crate::common::{tool_panel, CommonState, ContextualActions};
 use crate::game::{ChooseSomething, DrawBaselayer, PopupMsg, PromptInput, State, Transition};
@@ -21,6 +15,12 @@ use widgetry::{
     HorizontalAlignment, Key, Line, Outcome, Panel, Text, UpdateType, VerticalAlignment, Widget,
 };
 
+mod floodfill;
+mod objects;
+pub mod path_counter;
+mod polygons;
+pub mod shared_row;
+
 pub struct DebugMode {
     panel: Panel,
     common: CommonState,
diff --git a/game/src/devtools/mod.rs b/game/src/devtools/mod.rs
index 5c0d6750e4..7c7a2fcfc3 100644
--- a/game/src/devtools/mod.rs
+++ b/game/src/devtools/mod.rs
@@ -1,10 +1,3 @@
-mod destinations;
-mod kml;
-pub mod mapping;
-mod polygon;
-mod scenario;
-mod story;
-
 use crate::app::App;
 use crate::common::CityPicker;
 use crate::game::{ChooseSomething, DrawBaselayer, State, Transition};
@@ -16,6 +9,13 @@ use widgetry::{
     VerticalAlignment, Widget,
 };
 
+mod destinations;
+mod kml;
+pub mod mapping;
+mod polygon;
+mod scenario;
+mod story;
+
 pub struct DevToolsMode {
     panel: Panel,
 }
diff --git a/game/src/edit/mod.rs b/game/src/edit/mod.rs
index d9d0ea22f9..cf7797bdf0 100644
--- a/game/src/edit/mod.rs
+++ b/game/src/edit/mod.rs
@@ -1,13 +1,3 @@
-mod bulk;
-mod cluster_traffic_signals;
-mod lanes;
-mod routes;
-mod select;
-mod stop_signs;
-mod traffic_signals;
-mod validate;
-mod zones;
-
 pub use self::cluster_traffic_signals::ClusterTrafficSignalEditor;
 pub use self::lanes::LaneEditor;
 pub use self::routes::RouteEditor;
@@ -32,6 +22,16 @@ use widgetry::{
     Outcome, Panel, Text, TextExt, VerticalAlignment, Widget,
 };
 
+mod bulk;
+mod cluster_traffic_signals;
+mod lanes;
+mod routes;
+mod select;
+mod stop_signs;
+mod traffic_signals;
+mod validate;
+mod zones;
+
 pub struct EditMode {
     tool_panel: Panel,
     top_center: Panel,
diff --git a/game/src/edit/traffic_signals/mod.rs b/game/src/edit/traffic_signals/mod.rs
index e01e7a8977..589e5b044e 100644
--- a/game/src/edit/traffic_signals/mod.rs
+++ b/game/src/edit/traffic_signals/mod.rs
@@ -1,8 +1,3 @@
-mod edits;
-mod offsets;
-mod picker;
-mod preview;
-
 use crate::app::{App, ShowEverything};
 use crate::common::{CommonState, Warping};
 use crate::edit::{apply_map_edits, ConfirmDiscard};
@@ -22,6 +17,11 @@ use widgetry::{
     MultiButton, Outcome, Panel, RewriteColor, Text, TextExt, VerticalAlignment, Widget,
 };
 
+mod edits;
+mod offsets;
+mod picker;
+mod preview;
+
 // Welcome to one of the most overwhelmingly complicated parts of the UI...
 
 pub struct TrafficSignalEditor {
diff --git a/game/src/info/mod.rs b/game/src/info/mod.rs
index 993c5d7417..77bcaf8cec 100644
--- a/game/src/info/mod.rs
+++ b/game/src/info/mod.rs
@@ -1,12 +1,3 @@
-mod building;
-mod bus;
-mod debug;
-mod intersection;
-mod lane;
-mod parking_lot;
-mod person;
-mod trip;
-
 use crate::app::App;
 use crate::common::Warping;
 use crate::debug::path_counter::PathCounter;
@@ -27,6 +18,15 @@ use widgetry::{
     LinePlot, Outcome, Panel, PlotOptions, Series, TextExt, VerticalAlignment, Widget,
 };
 
+mod building;
+mod bus;
+mod debug;
+mod intersection;
+mod lane;
+mod parking_lot;
+mod person;
+mod trip;
+
 pub struct InfoPanel {
     tab: Tab,
     time: Time,
diff --git a/game/src/layer/mod.rs b/game/src/layer/mod.rs
index 9ae9e7a8bd..86b4062007 100644
--- a/game/src/layer/mod.rs
+++ b/game/src/layer/mod.rs
@@ -1,3 +1,10 @@
+use crate::app::App;
+use crate::common::HeatmapOptions;
+use crate::game::{DrawBaselayer, State, Transition};
+use crate::helpers::hotkey_btn;
+use crate::sandbox::dashboards;
+use widgetry::{Btn, EventCtx, GfxCtx, Key, Line, Outcome, Panel, TextExt, Widget};
+
 mod elevation;
 pub mod map;
 mod pandemic;
@@ -6,13 +13,6 @@ mod population;
 pub mod traffic;
 pub mod transit;
 
-use crate::app::App;
-use crate::common::HeatmapOptions;
-use crate::game::{DrawBaselayer, State, Transition};
-use crate::helpers::hotkey_btn;
-use crate::sandbox::dashboards;
-use widgetry::{Btn, EventCtx, GfxCtx, Key, Line, Outcome, Panel, TextExt, Widget};
-
 // TODO Good ideas in
 // https://towardsdatascience.com/top-10-map-types-in-data-visualization-b3a80898ea70
 
diff --git a/game/src/lib.rs b/game/src/lib.rs
index 89230e05b7..58d4cad0af 100644
--- a/game/src/lib.rs
+++ b/game/src/lib.rs
@@ -1,3 +1,12 @@
+#[macro_use]
+extern crate log;
+
+use abstutil::{CmdArgs, Timer};
+use geom::Duration;
+use sim::SimFlags;
+
+use crate::app::Flags;
+
 mod app;
 mod challenges;
 mod colors;
@@ -15,14 +24,6 @@ mod pregame;
 mod render;
 mod sandbox;
 
-#[macro_use]
-extern crate log;
-
-use crate::app::Flags;
-use abstutil::{CmdArgs, Timer};
-use geom::Duration;
-use sim::SimFlags;
-
 pub fn main() {
     let mut args = CmdArgs::new();
 
diff --git a/game/src/render/mod.rs b/game/src/render/mod.rs
index 7f21549c1d..2ff148922d 100644
--- a/game/src/render/mod.rs
+++ b/game/src/render/mod.rs
@@ -1,17 +1,3 @@
-mod area;
-mod bike;
-mod building;
-mod bus_stop;
-mod car;
-mod intersection;
-mod lane;
-mod map;
-mod parking_lot;
-mod pedestrian;
-mod road;
-pub mod traffic_signal;
-mod turn;
-
 use crate::app::App;
 use crate::colors::ColorScheme;
 use crate::helpers::ID;
@@ -28,6 +14,20 @@ use map_model::{IntersectionID, Map};
 use sim::{DrawCarInput, VehicleType};
 use widgetry::{GfxCtx, Prerender};
 
+mod area;
+mod bike;
+mod building;
+mod bus_stop;
+mod car;
+mod intersection;
+mod lane;
+mod map;
+mod parking_lot;
+mod pedestrian;
+mod road;
+pub mod traffic_signal;
+mod turn;
+
 pub const BIG_ARROW_THICKNESS: Distance = Distance::const_meters(0.5);
 
 pub const CROSSWALK_LINE_THICKNESS: Distance = Distance::const_meters(0.15);
diff --git a/game/src/sandbox/dashboards/mod.rs b/game/src/sandbox/dashboards/mod.rs
index b42f782da0..cbe2cf324e 100644
--- a/game/src/sandbox/dashboards/mod.rs
+++ b/game/src/sandbox/dashboards/mod.rs
@@ -1,3 +1,10 @@
+use crate::app::App;
+use crate::game::Transition;
+pub use commuter::CommuterPatterns;
+pub use traffic_signals::TrafficSignalDemand;
+pub use trip_table::FinishedTripTable;
+use widgetry::{Btn, Choice, EventCtx, Key, Line, Panel, TextExt, Widget};
+
 mod commuter;
 mod generic_trip_table;
 mod misc;
@@ -7,13 +14,6 @@ mod table;
 mod traffic_signals;
 mod trip_table;
 
-use crate::app::App;
-use crate::game::Transition;
-pub use commuter::CommuterPatterns;
-pub use traffic_signals::TrafficSignalDemand;
-pub use trip_table::FinishedTripTable;
-use widgetry::{Btn, Choice, EventCtx, Key, Line, Panel, TextExt, Widget};
-
 // Oh the dashboards melted, but we still had the radio
 #[derive(Clone, Copy, PartialEq, Debug)]
 pub enum DashTab {
diff --git a/game/src/sandbox/gameplay/mod.rs b/game/src/sandbox/gameplay/mod.rs
index 3842ccc2b1..8a69f48aab 100644
--- a/game/src/sandbox/gameplay/mod.rs
+++ b/game/src/sandbox/gameplay/mod.rs
@@ -1,10 +1,3 @@
-// TODO pub so challenges can grab cutscenes and SandboxMode can dispatch to actions. Weird?
-pub mod commute;
-pub mod fix_traffic_signals;
-pub mod freeform;
-pub mod play_scenario;
-pub mod tutorial;
-
 pub use self::freeform::spawn_agents_around;
 pub use self::tutorial::{Tutorial, TutorialPointer, TutorialState};
 use crate::app::App;
@@ -22,6 +15,13 @@ use widgetry::{
     lctrl, Btn, Color, EventCtx, GeomBatch, GfxCtx, Key, Line, Outcome, Panel, TextExt, Widget,
 };
 
+// TODO pub so challenges can grab cutscenes and SandboxMode can dispatch to actions. Weird?
+pub mod commute;
+pub mod fix_traffic_signals;
+pub mod freeform;
+pub mod play_scenario;
+pub mod tutorial;
+
 #[derive(PartialEq, Eq, PartialOrd, Ord, Clone)]
 pub enum GameplayMode {
     // TODO Maybe this should be "sandbox"
diff --git a/game/src/sandbox/mod.rs b/game/src/sandbox/mod.rs
index 068ac0fb61..826166dcb9 100644
--- a/game/src/sandbox/mod.rs
+++ b/game/src/sandbox/mod.rs
@@ -1,10 +1,3 @@
-pub mod dashboards;
-pub mod gameplay;
-mod misc_tools;
-mod speed;
-mod time_warp;
-mod uber_turns;
-
 use self::misc_tools::{RoutePreview, TurnExplorer};
 use crate::app::App;
 use crate::common::{tool_panel, CommonState, ContextualActions, IsochroneViewer, Minimap};
@@ -30,6 +23,13 @@ use widgetry::{
     TextExt, UpdateType, VerticalAlignment, Widget,
 };
 
+pub mod dashboards;
+pub mod gameplay;
+mod misc_tools;
+mod speed;
+mod time_warp;
+mod uber_turns;
+
 pub struct SandboxMode {
     gameplay: Box<dyn gameplay::GameplayState>,
     pub gameplay_mode: GameplayMode,
diff --git a/geom/src/lib.rs b/geom/src/lib.rs
index e408a81299..04e956469b 100644
--- a/geom/src/lib.rs
+++ b/geom/src/lib.rs
@@ -1,20 +1,3 @@
-mod angle;
-mod bounds;
-mod circle;
-mod distance;
-mod duration;
-mod find_closest;
-mod gps;
-mod line;
-mod percent;
-mod polygon;
-mod polyline;
-mod pt;
-mod ring;
-mod speed;
-mod stats;
-mod time;
-
 pub use crate::angle::Angle;
 pub use crate::bounds::{Bounds, GPSBounds};
 pub use crate::circle::Circle;
@@ -32,6 +15,23 @@ pub use crate::speed::Speed;
 pub use crate::stats::{HgramValue, Histogram, Statistic};
 pub use crate::time::Time;
 
+mod angle;
+mod bounds;
+mod circle;
+mod distance;
+mod duration;
+mod find_closest;
+mod gps;
+mod line;
+mod percent;
+mod polygon;
+mod polyline;
+mod pt;
+mod ring;
+mod speed;
+mod stats;
+mod time;
+
 // About 0.4 inches... which is quite tiny on the scale of things. :)
 pub const EPSILON_DIST: Distance = Distance::const_meters(0.01);
 
diff --git a/importer/src/main.rs b/importer/src/main.rs
index bd80bb8801..a701c563a0 100644
--- a/importer/src/main.rs
+++ b/importer/src/main.rs
@@ -1,3 +1,6 @@
+use configuration::{load_configuration, ImporterConfiguration};
+use dependencies::are_dependencies_callable;
+
 mod berlin;
 mod configuration;
 mod dependencies;
@@ -10,9 +13,6 @@ mod tel_aviv;
 mod utils;
 mod xian;
 
-use configuration::{load_configuration, ImporterConfiguration};
-use dependencies::are_dependencies_callable;
-
 // TODO Might be cleaner to express as a dependency graph?
 
 struct Job {
diff --git a/importer/src/soundcast/mod.rs b/importer/src/soundcast/mod.rs
index 135c554a6d..d360ba5a1f 100644
--- a/importer/src/soundcast/mod.rs
+++ b/importer/src/soundcast/mod.rs
@@ -1,5 +1,5 @@
-mod popdat;
-mod trips;
-
 pub use self::popdat::{import_data, PopDat};
 pub use self::trips::{make_weekday_scenario, make_weekday_scenario_with_everyone};
+
+mod popdat;
+mod trips;
diff --git a/map_editor/src/main.rs b/map_editor/src/main.rs
index c9d7aca39a..267d010121 100644
--- a/map_editor/src/main.rs
+++ b/map_editor/src/main.rs
@@ -1,6 +1,3 @@
-mod model;
-mod world;
-
 use abstutil::{CmdArgs, Timer};
 use geom::{Distance, Line, Polygon};
 use map_model::osm;
@@ -11,6 +8,9 @@ use widgetry::{
     Outcome, Panel, ScreenPt, Text, VerticalAlignment, Widget, GUI,
 };
 
+mod model;
+mod world;
+
 struct UI {
     model: Model,
     state: State,
diff --git a/map_model/src/edits/mod.rs b/map_model/src/edits/mod.rs
index 3150c79bf1..d042379634 100644
--- a/map_model/src/edits/mod.rs
+++ b/map_model/src/edits/mod.rs
@@ -2,9 +2,6 @@
 // the changes to a file (as PermanentMapEdits). See
 // https://dabreegster.github.io/abstreet/map/edits.html.
 
-mod compat;
-mod perma;
-
 use crate::make::initial::lane_specs::get_lane_specs_ltr;
 use crate::{
     connectivity, AccessRestrictions, BusRouteID, ControlStopSign, ControlTrafficSignal, Direction,
@@ -17,6 +14,9 @@ pub use perma::PermanentMapEdits;
 use serde::{Deserialize, Serialize};
 use std::collections::{BTreeMap, BTreeSet};
 
+mod compat;
+mod perma;
+
 // Represents changes to a map. Note this isn't serializable -- that's what PermanentMapEdits does.
 #[derive(Debug, Clone, PartialEq)]
 pub struct MapEdits {
diff --git a/map_model/src/lib.rs b/map_model/src/lib.rs
index 503c0f2212..f57aab6f51 100644
--- a/map_model/src/lib.rs
+++ b/map_model/src/lib.rs
@@ -21,17 +21,6 @@
 // - t = turn
 // - ts = traffic signal
 
-mod city;
-pub mod connectivity;
-mod edits;
-mod make;
-mod map;
-mod objects;
-pub mod osm;
-mod pathfind;
-pub mod raw;
-mod traversable;
-
 #[macro_use]
 extern crate log;
 
@@ -66,6 +55,17 @@ use geom::{Bounds, Distance, GPSBounds, Polygon};
 use serde::{Deserialize, Serialize};
 use std::collections::BTreeMap;
 
+mod city;
+pub mod connectivity;
+mod edits;
+mod make;
+mod map;
+mod objects;
+pub mod osm;
+mod pathfind;
+pub mod raw;
+mod traversable;
+
 // TODO Minimize uses of these!
 pub const NORMAL_LANE_THICKNESS: Distance = Distance::const_meters(2.5);
 pub(crate) const SERVICE_ROAD_LANE_THICKNESS: Distance = Distance::const_meters(1.5);
diff --git a/map_model/src/make/initial/mod.rs b/map_model/src/make/initial/mod.rs
index ee8cf017e7..3b108ff09a 100644
--- a/map_model/src/make/initial/mod.rs
+++ b/map_model/src/make/initial/mod.rs
@@ -1,9 +1,6 @@
 // Naming is confusing, but RawMap -> InitialMap -> Map. InitialMap is separate pretty much just
 // for the step of producing https://dabreegster.github.io/abstreet/map/importing/geometry.html.
 
-mod geometry;
-pub mod lane_specs;
-
 pub use self::geometry::intersection_polygon;
 use crate::raw::{OriginalRoad, RawMap, RawRoad};
 use crate::{osm, DrivingSide, IntersectionType};
@@ -12,6 +9,9 @@ use geom::{Bounds, Circle, Distance, PolyLine, Polygon, Pt2D};
 use lane_specs::LaneSpec;
 use std::collections::{BTreeMap, BTreeSet};
 
+mod geometry;
+pub mod lane_specs;
+
 pub struct InitialMap {
     pub roads: BTreeMap<OriginalRoad, Road>,
     pub intersections: BTreeMap<osm::NodeID, Intersection>,
diff --git a/map_model/src/make/mod.rs b/map_model/src/make/mod.rs
index 12aac01681..147fa74ade 100644
--- a/map_model/src/make/mod.rs
+++ b/map_model/src/make/mod.rs
@@ -1,16 +1,6 @@
 // See https://dabreegster.github.io/abstreet/map/importing/index.html for an overview. This module
 // covers the RawMap->Map stage.
 
-mod bridges;
-mod buildings;
-pub mod initial;
-mod parking_lots;
-mod remove_disconnected;
-pub mod traffic_signals;
-mod transit;
-pub mod turns;
-mod walking_turns;
-
 use crate::pathfind::Pathfinder;
 use crate::raw::{OriginalRoad, RawMap};
 use crate::{
@@ -22,6 +12,16 @@ use abstutil::{Parallelism, Timer};
 use geom::{Bounds, Distance, FindClosest, HashablePt2D, Speed, EPSILON_DIST};
 use std::collections::{BTreeMap, BTreeSet, HashMap, HashSet};
 
+mod bridges;
+mod buildings;
+pub mod initial;
+mod parking_lots;
+mod remove_disconnected;
+pub mod traffic_signals;
+mod transit;
+pub mod turns;
+mod walking_turns;
+
 impl Map {
     pub fn create_from_raw(mut raw: RawMap, build_ch: bool, timer: &mut Timer) -> Map {
         // Better to defer this and see RawMaps with more debug info in map_editor
diff --git a/map_model/src/pathfind/mod.rs b/map_model/src/pathfind/mod.rs
index 030b0e7702..9f64cd6443 100644
--- a/map_model/src/pathfind/mod.rs
+++ b/map_model/src/pathfind/mod.rs
@@ -1,13 +1,5 @@
 // Everything related to pathfinding through a map for different types of agents.
 
-mod ch;
-mod dijkstra;
-mod driving;
-mod node_map;
-// TODO tmp
-pub mod uber_turns;
-mod walking;
-
 pub use self::ch::ContractionHierarchyPathfinder;
 pub use self::driving::driving_cost;
 pub use self::walking::{walking_cost, WalkingNode};
@@ -22,6 +14,14 @@ use serde::{Deserialize, Serialize};
 use std::collections::{BTreeSet, VecDeque};
 use std::fmt;
 
+mod ch;
+mod dijkstra;
+mod driving;
+mod node_map;
+// TODO tmp
+pub mod uber_turns;
+mod walking;
+
 #[derive(Debug, Clone, Copy, Serialize, Deserialize, PartialEq, Eq, Hash, PartialOrd, Ord)]
 pub enum PathStep {
     // Original direction
diff --git a/sim/src/lib.rs b/sim/src/lib.rs
index 2bcf5c35d4..a2bce766a7 100644
--- a/sim/src/lib.rs
+++ b/sim/src/lib.rs
@@ -1,16 +1,3 @@
-mod analytics;
-mod cap;
-mod events;
-mod make;
-mod mechanics;
-mod pandemic;
-mod render;
-mod router;
-mod scheduler;
-mod sim;
-mod transit;
-mod trips;
-
 #[macro_use]
 extern crate log;
 
@@ -47,6 +34,19 @@ use map_model::{
 use serde::{Deserialize, Serialize};
 use std::fmt;
 
+mod analytics;
+mod cap;
+mod events;
+mod make;
+mod mechanics;
+mod pandemic;
+mod render;
+mod router;
+mod scheduler;
+mod sim;
+mod transit;
+mod trips;
+
 // http://pccsc.net/bicycle-parking-info/ says 68 inches, which is 1.73m
 pub const BIKE_LENGTH: Distance = Distance::const_meters(1.8);
 // These two must be < PARKING_SPOT_LENGTH
diff --git a/sim/src/make/mod.rs b/sim/src/make/mod.rs
index af5f8cf3ab..b6fd447d65 100644
--- a/sim/src/make/mod.rs
+++ b/sim/src/make/mod.rs
@@ -1,10 +1,5 @@
-mod activity_model;
-mod external;
-mod generator;
-mod load;
-mod modifier;
-mod scenario;
-mod spawner;
+use rand::{RngCore, SeedableRng};
+use rand_xorshift::XorShiftRng;
 
 pub use self::external::{ExternalPerson, ExternalTrip};
 pub use self::generator::{
@@ -16,8 +11,14 @@ pub use self::scenario::{
     IndividTrip, OffMapLocation, PersonSpec, Scenario, SpawnTrip, TripPurpose,
 };
 pub use self::spawner::{TripSpawner, TripSpec};
-use rand::{RngCore, SeedableRng};
-use rand_xorshift::XorShiftRng;
+
+mod activity_model;
+mod external;
+mod generator;
+mod load;
+mod modifier;
+mod scenario;
+mod spawner;
 
 // Need to explain this trick -- basically keeps consistency between two different simulations when
 // each one might make slightly different sequences of calls to the RNG.
diff --git a/sim/src/mechanics/mod.rs b/sim/src/mechanics/mod.rs
index 78c508cf15..a337c48320 100644
--- a/sim/src/mechanics/mod.rs
+++ b/sim/src/mechanics/mod.rs
@@ -1,12 +1,12 @@
+pub use self::driving::DrivingSimState;
+pub use self::intersection::IntersectionSimState;
+pub use self::parking::{ParkingSim, ParkingSimState};
+pub use self::queue::Queue;
+pub use self::walking::WalkingSimState;
+
 mod car;
 mod driving;
 mod intersection;
 mod parking;
 mod queue;
 mod walking;
-
-pub use self::driving::DrivingSimState;
-pub use self::intersection::IntersectionSimState;
-pub use self::parking::{ParkingSim, ParkingSimState};
-pub use self::queue::Queue;
-pub use self::walking::WalkingSimState;
diff --git a/sim/src/pandemic/mod.rs b/sim/src/pandemic/mod.rs
index a016d175cd..6f41aee45d 100644
--- a/sim/src/pandemic/mod.rs
+++ b/sim/src/pandemic/mod.rs
@@ -1,5 +1,3 @@
-mod pandemic;
-
 use geom::{Duration, Time};
 pub use pandemic::{Cmd, PandemicModel};
 use rand::Rng;
@@ -7,6 +5,8 @@ use rand_distr::{Distribution, Exp, Normal};
 use rand_xorshift::XorShiftRng;
 use std::ops;
 
+mod pandemic;
+
 #[derive(Clone, Copy, Debug, PartialEq, PartialOrd)]
 pub struct AnyTime(f64);
 
diff --git a/sim/src/sim/mod.rs b/sim/src/sim/mod.rs
index e6fd9caded..db25efb196 100644
--- a/sim/src/sim/mod.rs
+++ b/sim/src/sim/mod.rs
@@ -1,5 +1,3 @@
-mod queries;
-
 pub use self::queries::AgentProperties;
 use crate::{
     AgentID, AlertLocation, Analytics, CapSimState, CarID, Command, CreateCar, DrawCarInput,
@@ -23,6 +21,8 @@ use serde::{Deserialize, Serialize};
 use std::collections::{BTreeSet, HashSet};
 use std::panic;
 
+mod queries;
+
 // TODO Do something else.
 const BLIND_RETRY_TO_SPAWN: Duration = Duration::const_seconds(5.0);
 
diff --git a/widgetry/src/lib.rs b/widgetry/src/lib.rs
index 95164c53f5..9c6b2ca414 100644
--- a/widgetry/src/lib.rs
+++ b/widgetry/src/lib.rs
@@ -28,33 +28,6 @@
 #[macro_use]
 extern crate log;
 
-mod assets;
-#[cfg(any(feature = "glow-backend", feature = "wasm-backend"))]
-mod backend_glow;
-#[cfg(feature = "glow-backend")]
-mod backend_glow_native;
-#[cfg(feature = "wasm-backend")]
-mod backend_glow_wasm;
-mod canvas;
-mod color;
-mod drawing;
-mod event;
-mod event_ctx;
-mod geom;
-mod input;
-mod runner;
-mod screen_geom;
-mod style;
-mod svg;
-mod text;
-mod tools;
-mod widgets;
-
-mod backend {
-    #[cfg(any(feature = "glow-backend", feature = "wasm-backend"))]
-    pub use crate::backend_glow::*;
-}
-
 pub use crate::backend::Drawable;
 pub use crate::canvas::{Canvas, HorizontalAlignment, VerticalAlignment};
 pub use crate::color::{Color, Fill, LinearGradient, Texture};
@@ -87,6 +60,33 @@ pub use crate::widgets::spinner::Spinner;
 pub(crate) use crate::widgets::text_box::TextBox;
 pub use crate::widgets::{EdgeInsets, Outcome, Panel, Widget, WidgetImpl, WidgetOutput};
 
+mod assets;
+#[cfg(any(feature = "glow-backend", feature = "wasm-backend"))]
+mod backend_glow;
+#[cfg(feature = "glow-backend")]
+mod backend_glow_native;
+#[cfg(feature = "wasm-backend")]
+mod backend_glow_wasm;
+mod canvas;
+mod color;
+mod drawing;
+mod event;
+mod event_ctx;
+mod geom;
+mod input;
+mod runner;
+mod screen_geom;
+mod style;
+mod svg;
+mod text;
+mod tools;
+mod widgets;
+
+mod backend {
+    #[cfg(any(feature = "glow-backend", feature = "wasm-backend"))]
+    pub use crate::backend_glow::*;
+}
+
 pub struct Choice<T> {
     pub label: String,
     pub data: T,
diff --git a/widgetry/src/widgets/mod.rs b/widgetry/src/widgets/mod.rs
index 5240a265f8..c5e5411681 100644
--- a/widgetry/src/widgets/mod.rs
+++ b/widgetry/src/widgets/mod.rs
@@ -1,3 +1,18 @@
+use crate::widgets::containers::{Container, Nothing};
+pub use crate::widgets::panel::Panel;
+use crate::{
+    Button, Choice, Color, DeferDraw, DrawWithTooltips, Drawable, Dropdown, EventCtx, GeomBatch,
+    GfxCtx, JustDraw, Menu, RewriteColor, ScreenDims, ScreenPt, ScreenRectangle, Text, TextBox,
+};
+use geom::{Distance, Percent, Polygon};
+use std::collections::HashSet;
+use stretch::geometry::{Rect, Size};
+use stretch::node::{Node, Stretch};
+use stretch::number::Number;
+use stretch::style::{
+    AlignItems, Dimension, FlexDirection, FlexWrap, JustifyContent, PositionType, Style,
+};
+
 pub mod autocomplete;
 pub mod button;
 pub mod checkbox;
@@ -16,21 +31,6 @@ pub mod slider;
 pub mod spinner;
 pub mod text_box;
 
-use crate::widgets::containers::{Container, Nothing};
-pub use crate::widgets::panel::Panel;
-use crate::{
-    Button, Choice, Color, DeferDraw, DrawWithTooltips, Drawable, Dropdown, EventCtx, GeomBatch,
-    GfxCtx, JustDraw, Menu, RewriteColor, ScreenDims, ScreenPt, ScreenRectangle, Text, TextBox,
-};
-use geom::{Distance, Percent, Polygon};
-use std::collections::HashSet;
-use stretch::geometry::{Rect, Size};
-use stretch::node::{Node, Stretch};
-use stretch::number::Number;
-use stretch::style::{
-    AlignItems, Dimension, FlexDirection, FlexWrap, JustifyContent, PositionType, Style,
-};
-
 /// Create a new widget by implementing this trait. You can instantiate your widget by calling
 /// `Widget::new(Box::new(instance of your new widget))`, which gives you the usual style options.
 pub trait WidgetImpl: downcast_rs::Downcast {