diff --git a/src/conf.lua b/src/conf.lua
index ac743fb..838b6bd 100644
--- a/src/conf.lua
+++ b/src/conf.lua
@@ -1,14 +1,15 @@
 -- sync lovr/love positional cli arguments
 if arg[0] == nil and arg[1] ~= nil then arg[0] = arg[1] end
 
-package.path = package.path .. ';' .. 
-               arg[0] .. '/lovr/?.lua;' .. 
-               arg[0] .. '/lovr/?/init.lua;' .. 
-               arg[0] .. '/lib/?.lua'
-
 local runtime = ""
 
 if lovr ~= nil then runtime = "lovr" end 
 if love ~= nil then runtime = "love" end 
 
+package.path = package.path .. ';' .. 
+               arg[0] .. '/' .. runtime .. '/?.lua;' .. 
+               arg[0] .. '/' .. runtime .. '/?/init.lua;' .. 
+               arg[0] .. '/lib/?.lua'
+
+
 require( runtime .. "/conf")
diff --git a/src/ecs.lua b/src/ecs.lua
index dc13dc8..8acd3f8 100644
--- a/src/ecs.lua
+++ b/src/ecs.lua
@@ -1,37 +1,14 @@
-local api = ...
 local ecs = require("tiny-ecs")
 
-ecs.initers = {
-  renderer = function()
-    local renderer = ecs.processingSystem()
-    renderer.filter = ecs.requireAll('type') -- *TODO* might need filter later
-    function renderer:process(obj, pass)
-      local type = obj:type()
-      if type == "Model" then 
-        pass:setMaterial()
-        pass:setCullMode('none')
-        pass:draw(obj, 0, 0, 0, 1, 0, 1, 0, 0, 1)
-      end
-    end
-    ecs.addSystem( ecs.world, renderer )
-  end
-}
-
-ecs.enabled = true
-ecs.world   = ecs.world()
-ecs.world.update = ecs.update -- swap with extension update-func  
-
 ecs.init = function()
-  ecs.initers.renderer()
-end
-  
-ecs.update = function(dt)
-  --ecs.world.update( ecs.world, dt ) -- *TODO* different filter
-end
-
-ecs.draw = function(pass)
-  local opts = {
-  ecs.world.update( ecs.world, pass )
+  print("[i] loading ecs")
+  baseEntify = ecs.processingSystem()
+  baseEntify.filter = ecs.rejectAll('commit') 
+  baseEntify.updatethread = true
+  function baseEntify:onAdd(obj)
+    obj.commit = api.util.commit( api.world, api.ecs.requireAll('allowcommit') )
+  end
+  ecs.addSystem( api.world, baseEntify )
 end
 
 return ecs
diff --git a/src/ext/3DFile/main.lua b/src/ext/3DFile/main.lua
index cdb362f..3ba9de4 100644
--- a/src/ext/3DFile/main.lua
+++ b/src/ext/3DFile/main.lua
@@ -5,28 +5,22 @@ return {
   name = "3DFile",
   enabled = true,
 
-  init = function() 
-    modelLoader = ecs.processingSystem()
-    modelLoader.updatesystem = true 
-    modelLoader.filter = ecs.requireAll('URL', 'method', 'data', 'ok')
-    function modelLoader:process(req, dt)
-      if req.ok and req.model == nil then
-        if req.URL.extension == 'OBJ'  or 
-           req.URL.extension == 'GLB'  or 
-           req.URL.extension == 'GLTF' then
-
-          req.model = api.graphics.newModel( api.data.newBlob(req.data) )
-          api.world.add({ 
-            x = 0,
-            y = 0,
-            z = 0,
-            model = req.model,
-            req = req
-          })
-        end
+  loadasset = function(obj)
+    if( obj.URL ~= nil and obj.URLResponse ~= nil and
+       (obj.URL.extension == 'GLB'   or
+        obj.URL.extension == 'GLTF'  or 
+        obj.URL.extension == 'OBJ')) then 
+      if obj.URLResponse.ok then 
+        obj.model = api.graphics.newModel( api.data.newBlob( obj.URLResponse.data) )
+        obj.root  = (obj.URI.target == '_top')
+        obj.x = 0
+        obj.y = 0
+        obj.z = 0
+        obj.commit() -- notify systems
+      else
+        print("[3DFile] error: could not load " .. obj.URL.string )
       end
     end
-    api.world.add(modelLoader)
   end
 
 }
diff --git a/src/ext/URI/main.lua b/src/ext/URI/main.lua
new file mode 100644
index 0000000..d86a363
--- /dev/null
+++ b/src/ext/URI/main.lua
@@ -0,0 +1,42 @@
+local api = ...
+local ecs = api.ecs
+
+return {
+  name = "URI",
+  enabled = true,
+
+  init = function() 
+    local urlListener 
+    urlListener = ecs.processingSystem({
+      updatethread = true,
+      filter = ecs.requireAll('URI', ecs.rejectAll('URLResponse') ),
+      onAdd = function(self,obj)
+        api.ext.URI.to(obj.URI, nil, obj)
+      end
+    })
+    ecs.addSystem( api.world, urlListener )
+  end,
+
+  to = function(URI,refererer, obj)
+    obj = obj or {}
+    print("surfing to " .. URI.url)
+    obj.URL = api.url.parse(URI.url) 
+    obj.URLResponse = {}
+    foreach( api.protocol, function(name, p)
+      if obj.URL.protocol:match("^"..name) then 
+        protocol = p
+      end
+    end)
+    if protocol then
+      local status, data, headers = protocol.request(URI.url)
+      obj.URLResponse = {
+        ok          = (status >= 200 and status < 300),
+        status      = status,
+        data        = data,
+        headers     = headers 
+      }
+      api.exec( api.ext, 'loadasset', obj)
+    end
+  end
+
+}
diff --git a/src/ext/browser/main.lua b/src/ext/browser/main.lua
deleted file mode 100644
index 9c99a8f..0000000
--- a/src/ext/browser/main.lua
+++ /dev/null
@@ -1,38 +0,0 @@
-local api = ...
-local ecs = api.ecs
-
-return {
-  name = "browser",
-  enabled = true,
-
-  init = function() 
-    urlListener = ecs.processingSystem({
-      updatesystem = true,
-      filter = ecs.requireAll('url', 'method'),
-      onAdd = function(self,obj)
-        api.ext.browser.to(obj.url, nil, obj)
-      end
-    })
-    api.world.add(urlListener)
-  end,
-
-  to = function(url,refererer, opts)
-    opts = opts or {method = 'GET' }
-    print("surfing to " .. url)
-    local URL = api.url.parse(url) 
-    foreach( api.protocol, function(name, p)
-      if URL.protocol:match("^"..name) then 
-        protocol = p
-      end
-    end)
-    if protocol then
-      local status, data, headers = protocol.request(url)
-      opts.ok      = (status >= 200 and status < 300)
-      opts.status  = status
-      opts.data    = data
-      opts.headers = headers 
-      opts.URL     = URL
-    end
-  end
-
-}
diff --git a/src/ext/janusxr/main.lua b/src/ext/janusxr/main.lua
index acfab83..5798ad1 100644
--- a/src/ext/janusxr/main.lua
+++ b/src/ext/janusxr/main.lua
@@ -8,7 +8,7 @@ return {
 
   init = function() 
     JMLLoader = ecs.processingSystem()
-    JMLLoader.updatesystem = true 
+    JMLLoader.updatethread = true 
     JMLLoader.filter = ecs.requireAll('URL', 'method', 'data', 'ok')
     function JMLLoader:process(req, dt)
       if req.ok and req.xml == nil then
@@ -37,7 +37,7 @@ return {
         end
       end
     end
-    api.world.add(JMLLoader)
+    ecs.addSystem(api.world,JMLLoader)
 
   end,
 }
diff --git a/src/ext/xrfragments/main.lua b/src/ext/xrfragments/main.lua
index efc096c..530c888 100644
--- a/src/ext/xrfragments/main.lua
+++ b/src/ext/xrfragments/main.lua
@@ -9,7 +9,9 @@ return {
     local ecs   = api.ecs
     xrfsystem = ecs.system({
 
-      filter = ecs.filter('x', 'y', 'z', 'model'),
+      filter = ecs.requireAll('x', 'y', 'z', 'model'),
+      nocache = true,
+      filterDynamic = true,
 
       onAdd = function(self,obj)
 
diff --git a/src/lib/lust.lua b/src/lib/lust.lua
new file mode 100644
index 0000000..7a5d28a
--- /dev/null
+++ b/src/lib/lust.lua
@@ -0,0 +1,272 @@
+-- lust v0.2.0 - Lua test framework
+-- https://github.com/bjornbytes/lust
+-- MIT LICENSE
+
+local lust = {}
+lust.level = 0
+lust.passes = 0
+lust.errors = 0
+lust.befores = {}
+lust.afters = {}
+
+local red = string.char(27) .. '[31m'
+local green = string.char(27) .. '[32m'
+local normal = string.char(27) .. '[0m'
+local function indent(level) return string.rep('\t', level or lust.level) end
+
+function lust.nocolor()
+  red, green, normal = '', '', ''
+  return lust
+end
+
+function lust.describe(name, fn)
+  print(indent() .. name)
+  lust.level = lust.level + 1
+  fn()
+  lust.befores[lust.level] = {}
+  lust.afters[lust.level] = {}
+  lust.level = lust.level - 1
+end
+
+function lust.it(name, fn)
+  for level = 1, lust.level do
+    if lust.befores[level] then
+      for i = 1, #lust.befores[level] do
+        lust.befores[level][i](name)
+      end
+    end
+  end
+
+  local success, err = pcall(fn)
+  if success then lust.passes = lust.passes + 1
+  else lust.errors = lust.errors + 1 end
+  local color = success and green or red
+  local label = success and 'PASS' or 'FAIL'
+  print(indent() .. color .. label .. normal .. ' ' .. name)
+  if err then
+    print(indent(lust.level + 1) .. red .. tostring(err) .. normal)
+  end
+
+  for level = 1, lust.level do
+    if lust.afters[level] then
+      for i = 1, #lust.afters[level] do
+        lust.afters[level][i](name)
+      end
+    end
+  end
+end
+
+function lust.before(fn)
+  lust.befores[lust.level] = lust.befores[lust.level] or {}
+  table.insert(lust.befores[lust.level], fn)
+end
+
+function lust.after(fn)
+  lust.afters[lust.level] = lust.afters[lust.level] or {}
+  table.insert(lust.afters[lust.level], fn)
+end
+
+-- Assertions
+local function isa(v, x)
+  if type(x) == 'string' then
+    return type(v) == x,
+      'expected ' .. tostring(v) .. ' to be a ' .. x,
+      'expected ' .. tostring(v) .. ' to not be a ' .. x
+  elseif type(x) == 'table' then
+    if type(v) ~= 'table' then
+      return false,
+        'expected ' .. tostring(v) .. ' to be a ' .. tostring(x),
+        'expected ' .. tostring(v) .. ' to not be a ' .. tostring(x)
+    end
+
+    local seen = {}
+    local meta = v
+    while meta and not seen[meta] do
+      if meta == x then return true end
+      seen[meta] = true
+      meta = getmetatable(meta) and getmetatable(meta).__index
+    end
+
+    return false,
+      'expected ' .. tostring(v) .. ' to be a ' .. tostring(x),
+      'expected ' .. tostring(v) .. ' to not be a ' .. tostring(x)
+  end
+
+  error('invalid type ' .. tostring(x))
+end
+
+local function has(t, x)
+  for k, v in pairs(t) do
+    if v == x then return true end
+  end
+  return false
+end
+
+local function eq(t1, t2, eps)
+  if type(t1) ~= type(t2) then return false end
+  if type(t1) == 'number' then return math.abs(t1 - t2) <= (eps or 0) end
+  if type(t1) ~= 'table' then return t1 == t2 end
+  for k, _ in pairs(t1) do
+    if not eq(t1[k], t2[k], eps) then return false end
+  end
+  for k, _ in pairs(t2) do
+    if not eq(t2[k], t1[k], eps) then return false end
+  end
+  return true
+end
+
+local function stringify(t)
+  if type(t) == 'string' then return "'" .. tostring(t) .. "'" end
+  if type(t) ~= 'table' or getmetatable(t) and getmetatable(t).__tostring then return tostring(t) end
+  local strings = {}
+  for i, v in ipairs(t) do
+    strings[#strings + 1] = stringify(v)
+  end
+  for k, v in pairs(t) do
+    if type(k) ~= 'number' or k > #t or k < 1 then
+      strings[#strings + 1] = ('[%s] = %s'):format(stringify(k), stringify(v))
+    end
+  end
+  return '{ ' .. table.concat(strings, ', ') .. ' }'
+end
+
+local paths = {
+  [''] = { 'to', 'to_not' },
+  to = { 'have', 'equal', 'be', 'exist', 'fail', 'match' },
+  to_not = { 'have', 'equal', 'be', 'exist', 'fail', 'match', chain = function(a) a.negate = not a.negate end },
+  a = { test = isa },
+  an = { test = isa },
+  be = { 'a', 'an', 'truthy',
+    test = function(v, x)
+      return v == x,
+        'expected ' .. tostring(v) .. ' and ' .. tostring(x) .. ' to be the same',
+        'expected ' .. tostring(v) .. ' and ' .. tostring(x) .. ' to not be the same'
+    end
+  },
+  exist = {
+    test = function(v)
+      return v ~= nil,
+        'expected ' .. tostring(v) .. ' to exist',
+        'expected ' .. tostring(v) .. ' to not exist'
+    end
+  },
+  truthy = {
+    test = function(v)
+      return v,
+        'expected ' .. tostring(v) .. ' to be truthy',
+        'expected ' .. tostring(v) .. ' to not be truthy'
+    end
+  },
+  equal = {
+    test = function(v, x, eps)
+      local comparison = ''
+      local equal = eq(v, x, eps)
+
+      if not equal and (type(v) == 'table' or type(x) == 'table') then
+        comparison = comparison .. '\n' .. indent(lust.level + 1) .. 'LHS: ' .. stringify(v)
+        comparison = comparison .. '\n' .. indent(lust.level + 1) .. 'RHS: ' .. stringify(x)
+      end
+
+      return equal,
+        'expected ' .. tostring(v) .. ' and ' .. tostring(x) .. ' to be equal' .. comparison,
+        'expected ' .. tostring(v) .. ' and ' .. tostring(x) .. ' to not be equal'
+    end
+  },
+  have = {
+    test = function(v, x)
+      if type(v) ~= 'table' then
+        error('expected ' .. tostring(v) .. ' to be a table')
+      end
+
+      return has(v, x),
+        'expected ' .. tostring(v) .. ' to contain ' .. tostring(x),
+        'expected ' .. tostring(v) .. ' to not contain ' .. tostring(x)
+    end
+  },
+  fail = { 'with',
+    test = function(v)
+      return not pcall(v),
+        'expected ' .. tostring(v) .. ' to fail',
+        'expected ' .. tostring(v) .. ' to not fail'
+    end
+  },
+  with = {
+    test = function(v, pattern)
+      local ok, message = pcall(v)
+      return not ok and message:match(pattern),
+        'expected ' .. tostring(v) .. ' to fail with error matching "' .. pattern .. '"',
+        'expected ' .. tostring(v) .. ' to not fail with error matching "' .. pattern .. '"'
+    end
+  },
+  match = {
+    test = function(v, p)
+      if type(v) ~= 'string' then v = tostring(v) end
+      local result = string.find(v, p)
+      return result ~= nil,
+        'expected ' .. v .. ' to match pattern [[' .. p .. ']]',
+        'expected ' .. v .. ' to not match pattern [[' .. p .. ']]'
+    end
+  }
+}
+
+function lust.expect(v)
+  local assertion = {}
+  assertion.val = v
+  assertion.action = ''
+  assertion.negate = false
+
+  setmetatable(assertion, {
+    __index = function(t, k)
+      if has(paths[rawget(t, 'action')], k) then
+        rawset(t, 'action', k)
+        local chain = paths[rawget(t, 'action')].chain
+        if chain then chain(t) end
+        return t
+      end
+      return rawget(t, k)
+    end,
+    __call = function(t, ...)
+      if paths[t.action].test then
+        local res, err, nerr = paths[t.action].test(t.val, ...)
+        if assertion.negate then
+          res = not res
+          err = nerr or err
+        end
+        if not res then
+          error(err or 'unknown failure', 2)
+        end
+      end
+    end
+  })
+
+  return assertion
+end
+
+function lust.spy(target, name, run)
+  local spy = {}
+  local subject
+
+  local function capture(...)
+    table.insert(spy, {...})
+    return subject(...)
+  end
+
+  if type(target) == 'table' then
+    subject = target[name]
+    target[name] = capture
+  else
+    run = name
+    subject = target or function() end
+  end
+
+  setmetatable(spy, {__call = function(_, ...) return capture(...) end})
+
+  if run then run() end
+
+  return spy
+end
+
+lust.test = lust.it
+lust.paths = paths
+
+return lust
diff --git a/src/lovr/main.lua b/src/lovr/main.lua
index a2824e4..1785121 100644
--- a/src/lovr/main.lua
+++ b/src/lovr/main.lua
@@ -16,6 +16,8 @@ api.backend = backend
 -- decorate api
 api.protocol.http = require('http')
 local ecs = api.ecs
+ecs.filterDraw   = ecs.requireAll('drawthread')
+ecs.filterUpdate = ecs.requireAll('updatethread')
 
 
 -- ecs systems
@@ -48,11 +50,8 @@ function lovr.load()
 end
 
 function lovr.update(dt)
-    if lovr.system.isKeyDown("escape") then
-        lovr.event.quit()
-    end
     
-    ecs.update( api.world, dt, ecs.filter('updatesystem') )
+    ecs.update( api.world, dt, ecs.filterUpdate )
 
     iui.beginFrame(dt)
 
@@ -92,7 +91,7 @@ function lovr.draw(pass)
     end
 
     api.exec(api.ext, "draw",pass)
-    ecs.update( api.world, pass, ecs.filter('drawsystem') )
+    ecs.update( api.world, pass, ecs.filterDraw )
 
      -- Dot
     if selectedBox then
@@ -154,12 +153,12 @@ if launch.mode == "desktop" then
 end
 
 local initECS = function(ecs)
-  -- lovr.draw => ecs.drawsystem (render-logic thread)
+  -- lovr.draw => ecs.draw (render-logic thread)
   renderer = ecs.processingSystem()
-  renderer.filter     = ecs.requireAny('model')
-  renderer.drawsystem = true
+  renderer.filter        = ecs.requireAll('model') 
+  renderer.drawthread = true
   function renderer:process(obj, pass)
-    if obj['model'] ~= nil then 
+    if obj.model ~= nil and obj.root ~= nil then 
       pass:setMaterial()
       pass:setCullMode('none')
       pass:draw(
@@ -172,22 +171,13 @@ local initECS = function(ecs)
   end
   ecs.addSystem( api.world, renderer )
 
-  -- lovr.update => ecs updatesystem (game-logic thread)
-  local updater = ecs.processingSystem()
-  updater.updatesystem = true 
-  updater.filter = ecs.requireAll('update')
-  function updater:process(obj, dt)
-    print_r(obj['data'])
-  end
-  ecs.addSystem( api.world, updater )
-
 end
 
 function initInteractions(ecs)
 
   ecs.worldPhysics = lovr.physics.newWorld(0, 0, 0)
   interactionsUpdater = ecs.processingSystem()
-  interactionsUpdater.updatesystem = true 
+  interactionsUpdater.updatethread = true 
   interactionsUpdater.filter = ecs.requireAll('collider')
   -- collider vars
   interactionsUpdater.mouse = { released = false}
diff --git a/src/main.lua b/src/main.lua
index 164a677..f8ab809 100644
--- a/src/main.lua
+++ b/src/main.lua
@@ -1,5 +1,5 @@
 local util = require("util")
-local  ecs = require("tiny-ecs")
+local  ecs = require("ecs")
 
 api = {
   parser   = {
@@ -15,10 +15,6 @@ api = {
   exec     = function(...) util.exec(...) end -- calls function on each table item
 }
 
--- convenience wrappers
-api.world.add    = function(...) api.ecs.add( api.world, ...) end
-api.world.remove = function(...) api.ecs.remove( api.world, ...) end
-
 local runtime
 local runtimepath
 
@@ -26,11 +22,13 @@ if lovr ~= nil then runtime = { path = "lovr", api = lovr }  end
 if love ~= nil then runtime = { path = "love", api = love }  end 
 
 api = util.merge( api, runtime.api )
+
+require( runtime.path .. "/main")
+  
 util.loaddir( "ext",   api, api.ext )
 util.loaddir( "media", api, api.media )
-  
+ecs.init()
 api.exec( api.ext, 'init')
-require( runtime.path .. "/main")
 
 local url='https://coderofsalvation.codeberg.page/xrfragment-haxe/example/assets/example.glb?bar=1&f=2#foo'
 --local url = 'https://codeberg.org/coderofsalvation/xrfragment/raw/branch/main/assets/template/website/website.glb'
@@ -38,4 +36,4 @@ local url='https://coderofsalvation.codeberg.page/xrfragment-haxe/example/assets
 --local url = 'https://janusxr.org/index.html'
 
 
-api.world.add({ url = url, method = 'GET' })
+api.ecs.add( api.world, { URI = { url = url, method = 'GET', target = '_top' }  })
diff --git a/src/test/main.lua b/src/test/main.lua
new file mode 100644
index 0000000..5627be4
--- /dev/null
+++ b/src/test/main.lua
@@ -0,0 +1,19 @@
+local lust = require 'lust'
+local describe, it, expect = lust.describe, lust.it, lust.expect
+
+describe('my project', function()
+  lust.before(function()
+    -- This gets run before every test.
+  end)
+
+  describe('module1', function() -- Can be nested
+    it('feature1', function()
+      expect(1).to.be.a('number') -- Pass
+      expect('astring').to.equal('astring') -- Pass
+    end)
+
+    it('feature2', function()
+      expect(nil).to.exist() -- Fail
+    end)
+  end)
+end)
diff --git a/src/util.lua b/src/util.lua
index 200bc66..7ee6bf5 100644
--- a/src/util.lua
+++ b/src/util.lua
@@ -151,7 +151,6 @@ function print_r(t)
   print( util.dump(t) )
 end
 
-
 util.match = function(list,k,v)
   local ret = false
   foreach( list, function(K,V) 
@@ -160,4 +159,22 @@ util.match = function(list,k,v)
   return ret
 end
 
+-- recalculate filters for tiny-ecs systems 
+-- usage: entity.commit = util.commit(api.world)  -- once
+--        entity.commit() -- this recalculates the filtercache of systems
+util.commit = function(world) 
+  return function()
+    for j = 1, #world.entities do
+      local system = world.systems[j]
+      system.entities = {}
+      for j = 1, #world.entities do
+        local entity = world.entities[j]
+        if system.filter(system, entity) then
+          table.insert( system.entities, entity)
+        end
+      end
+    end
+  end
+end
+
 return util