diff --git a/package.json b/package.json
index 80e57d0..4d27d81 100644
--- a/package.json
+++ b/package.json
@@ -5,7 +5,6 @@
   "type": "module",
   "source": "src/index.ts",
   "main": "dist/index.js",
-  "types": "dist/types.d.ts",
   "scripts": {
     "watch": "tsc --watch",
     "build": "parcel build",
diff --git a/src/config/WorldEnv.ts b/src/config/WorldEnv.ts
index b3d32dd..c12697c 100644
--- a/src/config/WorldEnv.ts
+++ b/src/config/WorldEnv.ts
@@ -1,13 +1,13 @@
 import { Vector2, Vector3 } from 'three'
 
-import { ItemType } from '../factory/ItemsFactory'
-import { BlockType } from '../procgen/Biome'
-import { ProcItemConf } from '../tools/ProceduralGenerators'
-import { SchematicsBlocksMapping } from '../tools/SchematicLoader'
-import { BiomesRawConf, BlockMode } from '../utils/types'
-
-// import { NoiseSamplerParams } from '../procgen/NoiseSampler'
-// import { ProcLayerParams } from '../procgen/ProcLayer'
+import { ItemType } from '../factory/ItemsFactory.js'
+import { BlockType } from '../procgen/Biome.js'
+import { ProcItemConf } from '../tools/ProceduralGenerators.js'
+import { SchematicsBlocksMapping } from '../tools/SchematicLoader.js'
+import { BiomesRawConf, BlockMode } from '../utils/types.js'
+
+// import { NoiseSamplerParams } from '../procgen/NoiseSampler.js'
+// import { ProcLayerParams } from '../procgen/ProcLayer.js'
 
 export class WorldEnv {
   // eslint-disable-next-line no-use-before-define
diff --git a/src/config/demo-samples/configs/biome_landscapes.ts b/src/config/demo-samples/configs/biome_landscapes.ts
index 7a34f1f..d8ef54a 100644
--- a/src/config/demo-samples/configs/biome_landscapes.ts
+++ b/src/config/demo-samples/configs/biome_landscapes.ts
@@ -1,6 +1,6 @@
-import { BiomeType, BlockType } from '../../../index'
+import { BiomeType, BlockType } from '../../../index.js'
 
-import { SCHEMATICS_COLLECTIONS } from './schematics_collections'
+import { SCHEMATICS_COLLECTIONS } from './schematics_collections.js'
 
 const { alpine, temperate_forest, siberian } = SCHEMATICS_COLLECTIONS
 
diff --git a/src/config/demo-samples/configs/blocks_mappings.ts b/src/config/demo-samples/configs/blocks_mappings.ts
index c81a868..c4bfaf3 100644
--- a/src/config/demo-samples/configs/blocks_mappings.ts
+++ b/src/config/demo-samples/configs/blocks_mappings.ts
@@ -1,5 +1,5 @@
-import { BlockType } from '../../../index'
-import { typesNumbering } from '../../../utils/misc'
+import { BlockType } from '../../../index.js'
+import { typesNumbering } from '../../../utils/misc.js'
 
 /**
  * Extending world reserved blocks
diff --git a/src/config/demo-samples/configs/procedural_items.ts b/src/config/demo-samples/configs/procedural_items.ts
index 68774fb..2aa397f 100644
--- a/src/config/demo-samples/configs/procedural_items.ts
+++ b/src/config/demo-samples/configs/procedural_items.ts
@@ -1,4 +1,4 @@
-import { ProcItemCategory, ProcItemType } from '../../../index'
+import { ProcItemCategory, ProcItemType } from '../../../index.js'
 
 export const proc_items = {
   AppleTree_S: 'appletree_s',
diff --git a/src/config/demo-samples/configs/world_dev_setup.ts b/src/config/demo-samples/configs/world_dev_setup.ts
index bf462fe..1a2acda 100644
--- a/src/config/demo-samples/configs/world_dev_setup.ts
+++ b/src/config/demo-samples/configs/world_dev_setup.ts
@@ -1,13 +1,13 @@
-// import { SCHEMATICS_FILES_INDEX } from '../assets/schematics/index'
-import { WorldEnv } from '../../../index'
+// import { SCHEMATICS_FILES_INDEX } from '../assets/schematics/index.js'
+import { WorldEnv } from '../../../index.js'
 
-import { BIOMES_LANDSCAPES_CONFIG } from './biome_landscapes'
-import { PROC_ITEMS_CONFIG } from './procedural_items'
+import { BIOMES_LANDSCAPES_CONFIG } from './biome_landscapes.js'
+import { PROC_ITEMS_CONFIG } from './procedural_items.js'
 import {
   BLOCKS_COLOR_MAPPING,
   // ExtBlock,
   SCHEMATICS_BLOCKS_MAPPING,
-} from './blocks_mappings'
+} from './blocks_mappings.js'
 
 /**
  * @param worldEnv provide it to setup worker's own env or it will default to main thread env
diff --git a/src/datacontainers/ChunkContainer.ts b/src/datacontainers/ChunkContainer.ts
index e66ce11..3bb2e3d 100644
--- a/src/datacontainers/ChunkContainer.ts
+++ b/src/datacontainers/ChunkContainer.ts
@@ -1,6 +1,6 @@
 import { Vector2, Box3, Vector3 } from 'three'
 
-import { BlockMode, ChunkId, ChunkKey } from '../utils/types'
+import { BlockMode, ChunkId, ChunkKey } from '../utils/types.js'
 import {
   asVect3,
   asChunkBounds,
@@ -8,9 +8,9 @@ import {
   serializeChunkId,
   parseThreeStub,
   asVect2,
-} from '../utils/convert'
-import { WorldEnv } from '../config/WorldEnv'
-import { BlockType } from '../index'
+} from '../utils/convert.js'
+import { WorldEnv } from '../config/WorldEnv.js'
+import { BlockType } from '../index.js'
 
 enum ChunkAxisOrder {
   ZXY,
diff --git a/src/datacontainers/PatchBase.ts b/src/datacontainers/PatchBase.ts
index 7a70f61..911baca 100644
--- a/src/datacontainers/PatchBase.ts
+++ b/src/datacontainers/PatchBase.ts
@@ -1,13 +1,13 @@
 import { Vector2, Box2, Vector3 } from 'three'
 
-import { PatchKey } from '../utils/types'
+import { PatchKey } from '../utils/types.js'
 import {
   parsePatchKey,
   asPatchBounds,
   asVect2,
   parseThreeStub,
-} from '../utils/convert'
-import { WorldEnv } from '../index'
+} from '../utils/convert.js'
+import { WorldEnv } from '../index.js'
 
 // export class PatchChunkCommon<T> {
 
diff --git a/src/factory/ChunksFactory.ts b/src/factory/ChunksFactory.ts
index c9b21de..9c83d52 100644
--- a/src/factory/ChunksFactory.ts
+++ b/src/factory/ChunksFactory.ts
@@ -1,17 +1,17 @@
 // import { MathUtils, Vector3 } from 'three'
 import { Vector3 } from 'three'
 
-import { WorldEnv } from '../config/WorldEnv'
-import { asVect2, serializePatchId, asBox2 } from '../utils/convert'
-import { BlockMode, ChunkKey, PatchBlock } from '../utils/types'
+import { WorldEnv } from '../config/WorldEnv.js'
+import { asVect2, serializePatchId, asBox2 } from '../utils/convert.js'
+import { BlockMode, ChunkKey, PatchBlock } from '../utils/types.js'
 import {
   ChunkBuffer,
   ChunkContainer,
   ChunkMask,
-} from '../datacontainers/ChunkContainer'
-import { BlockType, Biome, BiomeType, DensityVolume } from '../index'
-import { GroundPatch, parseGroundFlags } from '../processing/GroundPatch'
-import { clamp } from '../utils/math'
+} from '../datacontainers/ChunkContainer.js'
+import { BlockType, Biome, BiomeType, DensityVolume } from '../index.js'
+import { GroundPatch, parseGroundFlags } from '../processing/GroundPatch.js'
+import { clamp } from '../utils/math.js'
 
 export class EmptyChunk extends ChunkContainer {
   constructor(chunkKey: ChunkKey) {
diff --git a/src/factory/ItemsFactory.ts b/src/factory/ItemsFactory.ts
index 9c99781..5329f44 100644
--- a/src/factory/ItemsFactory.ts
+++ b/src/factory/ItemsFactory.ts
@@ -1,9 +1,9 @@
 import { Box3, Vector3 } from 'three'
 
-import { ChunkContainer } from '../datacontainers/ChunkContainer'
-import { ProceduralItemGenerator } from '../tools/ProceduralGenerators'
-import { SchematicLoader } from '../tools/SchematicLoader'
-import { WorldEnv } from '../config/WorldEnv'
+import { ChunkContainer } from '../datacontainers/ChunkContainer.js'
+import { ProceduralItemGenerator } from '../tools/ProceduralGenerators.js'
+import { SchematicLoader } from '../tools/SchematicLoader.js'
+import { WorldEnv } from '../config/WorldEnv.js'
 
 export type ItemType = string
 export type SpawnedItems = Record<ItemType, Vector3[]>
diff --git a/src/index.ts b/src/index.ts
index ee52ac8..ffab002 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,49 +1,49 @@
 // Utils
 // export * as WorldUtils from './utils/index'
-export { getPatchId, asVect2, asVect3 } from './utils/convert'
-export { BlockMode } from './utils/types'
+export { getPatchId, asVect2, asVect3 } from './utils/convert.js'
+export { BlockMode } from './utils/types.js'
 // Processing
-export { ProcessingTask } from './processing/TaskProcessing'
-export { BatchProcess } from './processing/BatchProcessing'
+export { ProcessingTask } from './processing/TaskProcessing.js'
+export { BatchProcess } from './processing/BatchProcessing.js'
 export {
   BlocksProcessing,
   BlocksProcessingRecipe,
   BlockProcessor,
-} from './processing/BlocksProcessing'
-export { BoardProcessor, BlockCategory } from './processing/BoardProcessing'
+} from './processing/BlocksProcessing.js'
+export { BoardProcessor, BlockCategory } from './processing/BoardProcessing.js'
 export {
   ViewChunksBatch,
   LowerChunksBatch,
   UpperChunksBatch,
-} from './processing/ChunksBatch'
+} from './processing/ChunksBatch.js'
 export {
   PseudoDistributionMap,
   DistributionProfile,
-} from './processing/RandomDistributionMap'
-export { ChunksProcessor } from './processing/ChunksProcessing'
-export { ProcessingState } from './processing/TaskProcessing'
+} from './processing/RandomDistributionMap.js'
+export { ChunksProcessor } from './processing/ChunksProcessing.js'
+export { ProcessingState } from './processing/TaskProcessing.js'
 // Procgen
-export { Biome, BiomeType, BlockType } from './procgen/Biome'
-export { Heightmap } from './procgen/Heightmap'
-export { DensityVolume } from './procgen/DensityVolume'
+export { Biome, BiomeType, BlockType } from './procgen/Biome.js'
+export { Heightmap } from './procgen/Heightmap.js'
+export { DensityVolume } from './procgen/DensityVolume.js'
 // Data structures
 // export { GroundContainer, GroundCache } from './datacontainers/PatchesIndexer'
-export { ChunkContainer } from './datacontainers/ChunkContainer'
+export { ChunkContainer } from './datacontainers/ChunkContainer.js'
 // Factory
-export { ItemsInventory } from './factory/ItemsFactory'
-export { GroundChunk, EmptyChunk, CavesMask } from './factory/ChunksFactory'
+export { ItemsInventory } from './factory/ItemsFactory.js'
+export { GroundChunk, EmptyChunk, CavesMask } from './factory/ChunksFactory.js'
 // Tools
-export { SchematicLoader } from './tools/SchematicLoader'
+export { SchematicLoader } from './tools/SchematicLoader.js'
 export {
   ProceduralItemGenerator,
   ProcItemType,
   ProcItemCategory,
-} from './tools/ProceduralGenerators'
-// export * as ProceduralGenerators from './tools/ProceduralGenerators'
+} from './tools/ProceduralGenerators.js'
+// export * as ProceduralGenerators from './tools/ProceduralGenerators.js'
 // Config
-export { WorldEnv } from './config/WorldEnv'
+export { WorldEnv } from './config/WorldEnv.js'
 // export * as WorldDevSetup from './config/demo-samples/configs/world_dev_setup'
 export {
   EnvOverride,
   BlocksColorOverride,
-} from './config/demo-samples/configs/world_dev_setup'
+} from './config/demo-samples/configs/world_dev_setup.js'
diff --git a/src/processing/BatchProcessing.ts b/src/processing/BatchProcessing.ts
index 4a98f0a..d42a757 100644
--- a/src/processing/BatchProcessing.ts
+++ b/src/processing/BatchProcessing.ts
@@ -1,4 +1,4 @@
-import { ProcessingState, ProcessingTask } from './TaskProcessing'
+import { ProcessingState, ProcessingTask } from './TaskProcessing.js'
 
 export class BatchProcess<T extends ProcessingTask> {
   // eslint-disable-next-line no-use-before-define
diff --git a/src/processing/BoardProcessing.ts b/src/processing/BoardProcessing.ts
index 7855171..39eaa58 100644
--- a/src/processing/BoardProcessing.ts
+++ b/src/processing/BoardProcessing.ts
@@ -8,30 +8,30 @@ import {
   getPatchId,
   getUpperScalarId,
   serializePatchId,
-} from '../utils/convert'
+} from '../utils/convert.js'
 import {
   WorldEnv,
   ChunkContainer,
   BatchProcess,
   ChunksProcessor,
   BlockType,
-} from '../index'
-import { ProcLayer } from '../procgen/ProcLayer'
-import { BlockMode, ChunkId, PatchKey } from '../utils/types'
+} from '../index.js'
+import { ProcLayer } from '../procgen/ProcLayer.js'
+import { BlockMode, ChunkId, PatchKey } from '../utils/types.js'
 import {
   DataContainer,
   PatchBase,
   PatchElement,
-} from '../datacontainers/PatchBase'
-import { copySourceToTargetPatch } from '../utils/data'
+} from '../datacontainers/PatchBase.js'
+import { copySourceToTargetPatch } from '../utils/data.js'
 
 import {
   ItemsBaker,
   ItemsProcessingParams,
   ItemsProcessingRecipes,
-} from './ItemsProcessing'
-import { ProcessingTask } from './TaskProcessing'
-import { ChunksProcessingParams } from './ChunksProcessing'
+} from './ItemsProcessing.js'
+import { ProcessingTask } from './TaskProcessing.js'
+import { ChunksProcessingParams } from './ChunksProcessing.js'
 // import { UndegroundChunkset } from './ChunksProcessing'
 
 export enum BlockCategory {
diff --git a/src/processing/ChunksBatch.ts b/src/processing/ChunksBatch.ts
index 82dd2be..a307a3b 100644
--- a/src/processing/ChunksBatch.ts
+++ b/src/processing/ChunksBatch.ts
@@ -1,15 +1,15 @@
 import { Box2, Vector2 } from 'three'
 
-import { serializePatchId } from '../utils/convert'
-import { PatchKey } from '../utils/types'
+import { serializePatchId } from '../utils/convert.js'
+import { PatchKey } from '../utils/types.js'
 
-import { BatchProcess } from './BatchProcessing'
+import { BatchProcess } from './BatchProcessing.js'
 import {
   ChunksProcessor,
   lowerChunksProcessingParams,
   upperChunksProcessingParams,
-} from './ChunksProcessing'
-import { ProcessingState } from './TaskProcessing'
+} from './ChunksProcessing.js'
+import { ProcessingState } from './TaskProcessing.js'
 
 // const { patchSize, patchDimensions } = WorldEnv.current
 
diff --git a/src/processing/ChunksProcessing.ts b/src/processing/ChunksProcessing.ts
index 07b15b3..6851c52 100644
--- a/src/processing/ChunksProcessing.ts
+++ b/src/processing/ChunksProcessing.ts
@@ -1,23 +1,23 @@
 import { Vector2 } from 'three'
 
-import { WorldEnv } from '../config/WorldEnv'
+import { WorldEnv } from '../config/WorldEnv.js'
 import {
   parsePatchKey,
   asVect3,
   serializeChunkId,
   asPatchBounds,
-} from '../utils/convert'
-import { ChunkIndex, PatchId, PatchKey } from '../utils/types'
+} from '../utils/convert.js'
+import { ChunkIndex, PatchId, PatchKey } from '../utils/types.js'
 import {
   ChunkContainer,
   ChunkStub,
   defaultDataEncoder,
-} from '../datacontainers/ChunkContainer'
-import { CavesMask, EmptyChunk, GroundChunk } from '../factory/ChunksFactory'
+} from '../datacontainers/ChunkContainer.js'
+import { CavesMask, EmptyChunk, GroundChunk } from '../factory/ChunksFactory.js'
 
-import { GroundPatch } from './GroundPatch'
-import { ProcessingState, ProcessingTask } from './TaskProcessing'
-import { ItemsBaker } from './ItemsProcessing'
+import { GroundPatch } from './GroundPatch.js'
+import { ProcessingState, ProcessingTask } from './TaskProcessing.js'
+import { ItemsBaker } from './ItemsProcessing.js'
 const chunksRange = WorldEnv.current.chunks.range
 const { patchDimensions: patchDims } = WorldEnv.current
 
diff --git a/src/processing/GroundPatch.ts b/src/processing/GroundPatch.ts
index 76c9a9f..ae0921e 100644
--- a/src/processing/GroundPatch.ts
+++ b/src/processing/GroundPatch.ts
@@ -6,9 +6,9 @@ import {
   PatchBlock,
   PatchBoundId,
   PatchKey,
-} from '../utils/types'
-import { asVect3, asVect2 } from '../utils/convert'
-import { BlockMode, Heightmap, WorldEnv } from '../index'
+} from '../utils/types.js'
+import { asVect3, asVect2 } from '../utils/convert.js'
+import { BlockMode, Heightmap, WorldEnv } from '../index.js'
 import {
   Biome,
   BiomeInfluence,
@@ -16,14 +16,14 @@ import {
   BiomeType,
   BlockType,
   ReverseBiomeNumericType,
-} from '../procgen/Biome'
+} from '../procgen/Biome.js'
 import {
   PatchBase,
   PatchDataContainer,
   PatchStub,
-} from '../datacontainers/PatchBase'
-import { getPatchBoundingPoints } from '../utils/spatial'
-import { bilinearInterpolation } from '../utils/math'
+} from '../datacontainers/PatchBase.js'
+import { getPatchBoundingPoints } from '../utils/spatial.js'
+import { bilinearInterpolation } from '../utils/math.js'
 
 export type PatchBoundingBiomes = Record<PatchBoundId, BiomeInfluence>
 
diff --git a/src/processing/ItemsProcessing.ts b/src/processing/ItemsProcessing.ts
index ad86402..a90ae4d 100644
--- a/src/processing/ItemsProcessing.ts
+++ b/src/processing/ItemsProcessing.ts
@@ -1,21 +1,25 @@
 import { Box2, Box3, Vector3 } from 'three'
 
-import { ChunkContainer, ChunkStub } from '../datacontainers/ChunkContainer'
+import { ChunkContainer, ChunkStub } from '../datacontainers/ChunkContainer.js'
 import {
   Biome,
   BlocksProcessing,
   DistributionProfile,
   ProcessingTask,
   PseudoDistributionMap,
-} from '../index'
-import { DistributionParams } from '../procgen/BlueNoisePattern'
-import { asPatchBounds, asVect2, asVect3 } from '../utils/convert'
-import { PatchKey } from '../utils/types'
-import { WorldEnv } from '../config/WorldEnv'
-import { ItemsInventory, ItemType, SpawnedItems } from '../factory/ItemsFactory'
-
-import { GroundPatch } from './GroundPatch'
-import { DistributionProfiles } from './RandomDistributionMap'
+} from '../index.js'
+import { DistributionParams } from '../procgen/BlueNoisePattern.js'
+import { asPatchBounds, asVect2, asVect3 } from '../utils/convert.js'
+import { PatchKey } from '../utils/types.js'
+import { WorldEnv } from '../config/WorldEnv.js'
+import {
+  ItemsInventory,
+  ItemType,
+  SpawnedItems,
+} from '../factory/ItemsFactory.js'
+
+import { GroundPatch } from './GroundPatch.js'
+import { DistributionProfiles } from './RandomDistributionMap.js'
 
 const defaultDistribution: DistributionParams = {
   ...DistributionProfiles[DistributionProfile.MEDIUM],
diff --git a/src/processing/RandomDistributionMap.ts b/src/processing/RandomDistributionMap.ts
index 30dce48..d2626c0 100644
--- a/src/processing/RandomDistributionMap.ts
+++ b/src/processing/RandomDistributionMap.ts
@@ -1,14 +1,14 @@
 import alea from 'alea'
 import { Box2, Vector2 } from 'three'
 
-import { ProcLayer } from '../procgen/ProcLayer'
+import { ProcLayer } from '../procgen/ProcLayer.js'
 import {
   BlueNoisePattern,
   DistributionParams,
-} from '../procgen/BlueNoisePattern'
-import { asVect3, getPatchIds } from '../utils/convert'
-import { WorldEnv } from '../config/WorldEnv'
-import { ItemType } from '../factory/ItemsFactory'
+} from '../procgen/BlueNoisePattern.js'
+import { asVect3, getPatchIds } from '../utils/convert.js'
+import { WorldEnv } from '../config/WorldEnv.js'
+import { ItemType } from '../factory/ItemsFactory.js'
 
 const distDefaults = {
   aleaSeed: 'treeMap',
diff --git a/src/processing/TaskProcessing.ts b/src/processing/TaskProcessing.ts
index 56edf30..f34f6dc 100644
--- a/src/processing/TaskProcessing.ts
+++ b/src/processing/TaskProcessing.ts
@@ -1,7 +1,7 @@
 import workerpool from 'workerpool'
 
-import { WorldEnv } from '../index'
-import { parseThreeStub } from '../utils/convert'
+import { WorldEnv } from '../index.js'
+import { parseThreeStub } from '../utils/convert.js'
 
 const toStubs = (res: any) =>
   res instanceof Array
diff --git a/src/procgen/Biome.ts b/src/procgen/Biome.ts
index 05b2d48..85c9dde 100644
--- a/src/procgen/Biome.ts
+++ b/src/procgen/Biome.ts
@@ -2,25 +2,25 @@ import { Vector2, Vector3 } from 'three'
 
 // import { MappingProfiles, ProfilePreset } from "../tools/MappingPresets"
 // import {  smoothstep as smoothStep } from 'three/src/math/MathUtils'
-import { LinkedList } from '../datacontainers/LinkedList'
+import { LinkedList } from '../datacontainers/LinkedList.js'
 import {
   BiomeLandKey,
   BiomesConf,
   BiomesRawConf,
   LandConfigFields,
   BiomeLands,
-} from '../utils/types'
-import { WorldEnv } from '../index'
-import { clamp, roundToDec, smoothStep } from '../utils/math'
+} from '../utils/types.js'
+import { WorldEnv } from '../index.js'
+import { clamp, roundToDec, smoothStep } from '../utils/math.js'
 import {
   findMatchingRange,
   MappingRangeSorter,
   typesNumbering,
-} from '../utils/misc'
-import { asVect3 } from '../utils/convert'
-import { ItemType } from '../factory/ItemsFactory'
+} from '../utils/misc.js'
+import { asVect3 } from '../utils/convert.js'
+import { ItemType } from '../factory/ItemsFactory.js'
 
-import { ProcLayer } from './ProcLayer'
+import { ProcLayer } from './ProcLayer.js'
 
 // reserved native block types
 export enum BlockType {
diff --git a/src/procgen/DensityVolume.ts b/src/procgen/DensityVolume.ts
index 48add99..ab811db 100644
--- a/src/procgen/DensityVolume.ts
+++ b/src/procgen/DensityVolume.ts
@@ -1,6 +1,6 @@
 import { Vector3 } from 'three'
 
-import { NoiseDimension, NoiseSampler } from './NoiseSampler'
+import { NoiseDimension, NoiseSampler } from './NoiseSampler.js'
 
 export class DensityVolume {
   // eslint-disable-next-line no-use-before-define
diff --git a/src/procgen/Heightmap.ts b/src/procgen/Heightmap.ts
index 67d8fa8..ce4493e 100644
--- a/src/procgen/Heightmap.ts
+++ b/src/procgen/Heightmap.ts
@@ -1,8 +1,8 @@
 import { Vector3 } from 'three'
 
-import { ProcLayer } from './ProcLayer'
-import { Biome, BiomeInfluence } from './Biome'
-import { BlendMode, getCompositor } from './NoiseComposition'
+import { ProcLayer } from './ProcLayer.js'
+import { Biome, BiomeInfluence } from './Biome.js'
+import { BlendMode, getCompositor } from './NoiseComposition.js'
 
 const MODULATION_THRESHOLD = 0.318
 
diff --git a/src/procgen/NoiseSampler.ts b/src/procgen/NoiseSampler.ts
index b258823..579af21 100644
--- a/src/procgen/NoiseSampler.ts
+++ b/src/procgen/NoiseSampler.ts
@@ -2,7 +2,7 @@ import { createNoise2D, createNoise3D, createNoise4D } from 'simplex-noise'
 import alea from 'alea'
 import { Vector2, Vector3 } from 'three'
 
-import { clamp } from '../utils/math'
+import { clamp } from '../utils/math.js'
 
 export type InputType = Vector2 | Vector3
 export type Generator = (input: InputType) => number
diff --git a/src/procgen/ProcLayer.ts b/src/procgen/ProcLayer.ts
index cacf98d..0b858da 100644
--- a/src/procgen/ProcLayer.ts
+++ b/src/procgen/ProcLayer.ts
@@ -1,6 +1,6 @@
 import { Vector3 } from 'three'
 
-import { InputType, NoiseSampler } from './NoiseSampler'
+import { InputType, NoiseSampler } from './NoiseSampler.js'
 
 export type ProcLayerParams = {
   spreading: number
diff --git a/src/tools/ProceduralGenerators.ts b/src/tools/ProceduralGenerators.ts
index 60df072..6f1958a 100644
--- a/src/tools/ProceduralGenerators.ts
+++ b/src/tools/ProceduralGenerators.ts
@@ -1,8 +1,8 @@
 import { Vector3, Vector2, Box3 } from 'three'
 
-import { asVect2 } from '../utils/convert'
-import { ChunkContainer } from '../datacontainers/ChunkContainer'
-import { BlockType } from '../procgen/Biome'
+import { asVect2 } from '../utils/convert.js'
+import { ChunkContainer } from '../datacontainers/ChunkContainer.js'
+import { BlockType } from '../procgen/Biome.js'
 
 export enum ProcItemCategory {
   Tree,
diff --git a/src/tools/SchematicLoader.ts b/src/tools/SchematicLoader.ts
index a7960a8..8cb367c 100644
--- a/src/tools/SchematicLoader.ts
+++ b/src/tools/SchematicLoader.ts
@@ -1,10 +1,10 @@
 import Pako from 'pako'
 import { Box3, Vector3 } from 'three'
 
-import { NBTReader } from '../third-party/nbt_custom'
-import { BlockType } from '../procgen/Biome'
-import { ChunkContainer } from '../datacontainers/ChunkContainer'
-import { WorldEnv } from '../config/WorldEnv'
+import { NBTReader } from '../third-party/nbt_custom.js'
+import { BlockType } from '../procgen/Biome.js'
+import { ChunkContainer } from '../datacontainers/ChunkContainer.js'
+import { WorldEnv } from '../config/WorldEnv.js'
 
 export type SchematicsBlocksMapping = Record<string, BlockType>
 
diff --git a/src/utils/convert.ts b/src/utils/convert.ts
index 3fe2bc3..ed1a1c6 100644
--- a/src/utils/convert.ts
+++ b/src/utils/convert.ts
@@ -1,6 +1,6 @@
 import { Box2, Box3, Vector2, Vector2Like, Vector3, Vector3Like } from 'three'
 
-import { ChunkKey, PatchId, PatchKey } from './types'
+import { ChunkKey, PatchId, PatchKey } from './types.js'
 
 const asVect2 = (v3: Vector3) => {
   return new Vector2(v3.x, v3.z)
diff --git a/src/utils/data.ts b/src/utils/data.ts
index c1dc1c6..8d838fa 100644
--- a/src/utils/data.ts
+++ b/src/utils/data.ts
@@ -4,7 +4,7 @@
 
 import { Box2, Vector2 } from 'three'
 
-import { PatchDataContainer } from '../datacontainers/PatchBase'
+import { PatchDataContainer } from '../datacontainers/PatchBase.js'
 
 // copy occurs only on the overlapping global pos region of both containers
 export const copySourceToTargetPatch = (
diff --git a/src/utils/index.ts b/src/utils/index.ts
index 5e89532..ad10a9f 100644
--- a/src/utils/index.ts
+++ b/src/utils/index.ts
@@ -1,5 +1,5 @@
-export * as convert from './convert'
-export * as math from './math'
-export * as data from './data'
-export * as misc from './misc'
-export * as spatial from './spatial'
+export * as convert from './convert.js'
+export * as math from './math.js'
+export * as data from './data.js'
+export * as misc from './misc.js'
+export * as spatial from './spatial.js'
diff --git a/src/utils/math.ts b/src/utils/math.ts
index 3ade77d..6f93436 100644
--- a/src/utils/math.ts
+++ b/src/utils/math.ts
@@ -1,6 +1,6 @@
 import { Box2, Box3, Vector2, Vector3 } from 'three'
 
-import { PatchBoundId } from './types'
+import { PatchBoundId } from './types.js'
 
 /**
  * @param point input point inside bounding box
diff --git a/src/utils/misc.ts b/src/utils/misc.ts
index 6777c7a..146f329 100644
--- a/src/utils/misc.ts
+++ b/src/utils/misc.ts
@@ -1,4 +1,4 @@
-import { BiomeLands, LandConfigFields } from './types'
+import { BiomeLands, LandConfigFields } from './types.js'
 
 // const MappingRangeFinder = (item: LinkedList<MappingData>, inputVal: number) => item.next && inputVal > (item.next.data as MappingData).x
 export const MappingRangeSorter = (
diff --git a/src/utils/spatial.ts b/src/utils/spatial.ts
index b0ef2ab..382d4f0 100644
--- a/src/utils/spatial.ts
+++ b/src/utils/spatial.ts
@@ -1,6 +1,10 @@
 import { Box2, Vector2, Vector3 } from 'three'
 
-import { PatchBoundingPoints, SurfaceNeighbour, VolumeNeighbour } from './types'
+import {
+  PatchBoundingPoints,
+  SurfaceNeighbour,
+  VolumeNeighbour,
+} from './types.js'
 
 /**
  * Orthogonal or direct 2D neighbours e.g.
diff --git a/src/utils/types.ts b/src/utils/types.ts
index c0a9268..4dcf121 100644
--- a/src/utils/types.ts
+++ b/src/utils/types.ts
@@ -1,9 +1,9 @@
 import { Vector2, Vector3 } from 'three'
 
-import { GroundBlockData } from '../processing/GroundPatch'
-import { BiomeType, BlockType } from '../procgen/Biome'
-import { LinkedList } from '../datacontainers/LinkedList'
-import { ItemType } from '../factory/ItemsFactory'
+import { GroundBlockData } from '../processing/GroundPatch.js'
+import { BiomeType, BlockType } from '../procgen/Biome.js'
+import { LinkedList } from '../datacontainers/LinkedList.js'
+import { ItemType } from '../factory/ItemsFactory.js'
 
 export type Block<T> = {
   pos: Vector3
diff --git a/tsconfig.json b/tsconfig.json
index 13f84c5..20d0622 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -23,8 +23,9 @@
     "useUnknownInCatchVariables": true,
 
     /* Modules */
-    "module": "ESNext",
-    "moduleResolution": "bundler",
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext",
+    "typeRoots": ["src/@types", "./node_modules/@types"],
 
     /* Emit */
     "declaration": true,
@@ -42,5 +43,7 @@
 
     /* Language and Environment */
     "target": "ESNext"
-  }
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "dist"]
 }