diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,3 +1,9 @@
 # Changelog for cloudflare
 
 ## Unreleased changes
+
+## 0.2.0.0
+
+### Breaking changes
+
+- Use `HashMap Text Attribute` instead of `[(Text, Attribute)]` as attributes
diff --git a/Setup.hs b/Setup.hs
--- a/Setup.hs
+++ b/Setup.hs
@@ -1,2 +1,4 @@
 import Distribution.Simple
+
+
 main = defaultMain
diff --git a/hs-opentelemetry-instrumentation-cloudflare.cabal b/hs-opentelemetry-instrumentation-cloudflare.cabal
--- a/hs-opentelemetry-instrumentation-cloudflare.cabal
+++ b/hs-opentelemetry-instrumentation-cloudflare.cabal
@@ -1,20 +1,20 @@
 cabal-version: 1.12
 
--- This file has been generated from package.yaml by hpack version 0.34.4.
+-- This file has been generated from package.yaml by hpack version 0.35.2.
 --
 -- see: https://github.com/sol/hpack
 
-name:           hs-opentelemetry-instrumentation-cloudflare
-version:        0.1.0.0
-description:    Please see the README on GitHub at <https://github.com/iand675/hs-opentelemetry/tree/main/instrumentation/cloudflare#readme>
-homepage:       https://github.com/iand675/hs-opentelemetry#readme
-bug-reports:    https://github.com/iand675/hs-opentelemetry/issues
-author:         Ian Duncan
-maintainer:     ian@iankduncan.com
-copyright:      2021 Ian Duncan
-license:        BSD3
-license-file:   LICENSE
-build-type:     Simple
+name:               hs-opentelemetry-instrumentation-cloudflare
+version:            0.2.0.0
+description:        Please see the README on GitHub at <https://github.com/iand675/hs-opentelemetry/tree/main/instrumentation/cloudflare#readme>
+homepage:           https://github.com/iand675/hs-opentelemetry#readme
+bug-reports:        https://github.com/iand675/hs-opentelemetry/issues
+author:             Ian Duncan, Jade Lovelace
+maintainer:         ian@iankduncan.com
+copyright:          2023 Ian Duncan, Mercury Technologies
+license:            BSD3
+license-file:       LICENSE
+build-type:         Simple
 extra-source-files:
     README.md
     ChangeLog.md
@@ -33,10 +33,11 @@
   build-depends:
       base >=4.7 && <5
     , case-insensitive
-    , hs-opentelemetry-api ==0.0.3.*
+    , hs-opentelemetry-api ==0.1.*
     , hs-opentelemetry-instrumentation-wai
     , http-types
     , text
+    , unordered-containers
     , wai
   default-language: Haskell2010
 
@@ -51,10 +52,11 @@
   build-depends:
       base >=4.7 && <5
     , case-insensitive
-    , hs-opentelemetry-api ==0.0.3.*
+    , hs-opentelemetry-api ==0.1.*
     , hs-opentelemetry-instrumentation-conduit
     , hs-opentelemetry-instrumentation-wai
     , http-types
     , text
+    , unordered-containers
     , wai
   default-language: Haskell2010
diff --git a/src/OpenTelemetry/Instrumentation/Cloudflare.hs b/src/OpenTelemetry/Instrumentation/Cloudflare.hs
--- a/src/OpenTelemetry/Instrumentation/Cloudflare.hs
+++ b/src/OpenTelemetry/Instrumentation/Cloudflare.hs
@@ -1,41 +1,48 @@
+{-# LANGUAGE OverloadedLists #-}
 {-# LANGUAGE OverloadedStrings #-}
+
 module OpenTelemetry.Instrumentation.Cloudflare where
 
+import Control.Monad (forM_)
+import qualified Data.CaseInsensitive as CI
+import qualified Data.HashMap.Strict as H
+import qualified Data.List
+import Data.Maybe
 import qualified Data.Text as T
 import qualified Data.Text.Encoding as T
 import Network.Wai
-import OpenTelemetry.Attributes (PrimitiveAttribute(..), ToAttribute (..))
+import OpenTelemetry.Attributes (PrimitiveAttribute (..), ToAttribute (..))
 import OpenTelemetry.Context
 import OpenTelemetry.Instrumentation.Wai (requestContext)
 import OpenTelemetry.Trace.Core (addAttributes)
-import Control.Monad (forM_)
-import Data.Maybe
-import qualified Data.List
-import qualified Data.CaseInsensitive as CI
 
+
 cloudflareInstrumentationMiddleware :: Middleware
 cloudflareInstrumentationMiddleware app req sendResp = do
   let mCtxt = requestContext req
   forM_ mCtxt $ \ctxt -> do
     forM_ (lookupSpan ctxt) $ \span_ -> do
-      addAttributes span_ $ concatMap
-        (\hn -> case Data.List.lookup hn $ requestHeaders req of
-            Nothing -> []
-            Just val -> 
-              [ ("http.request.header." <> T.decodeUtf8 (CI.foldedCase hn)
-                , toAttribute $ T.decodeUtf8 val
-                )
-              ]
-        )
-        headers
+      addAttributes span_ $
+        H.unions $
+          fmap
+            ( \hn -> case Data.List.lookup hn $ requestHeaders req of
+                Nothing -> []
+                Just val ->
+                  [
+                    ( "http.request.header." <> T.decodeUtf8 (CI.foldedCase hn)
+                    , toAttribute $ T.decodeUtf8 val
+                    )
+                  ]
+            )
+            headers
   app req sendResp
   where
     headers =
       [ "cf-connecting-ip"
       , "true-client-ip"
       , "cf-ray"
-      -- CF-Visitor
-      , "cf-ipcountry"
-      -- CDN-Loop
-      , "cf-worker"
+      , -- CF-Visitor
+        "cf-ipcountry"
+      , -- CDN-Loop
+        "cf-worker"
       ]
diff --git a/test/Spec.hs b/test/Spec.hs
--- a/test/Spec.hs
+++ b/test/Spec.hs
@@ -1,2 +1,3 @@
+
 main :: IO ()
 main = putStrLn "Test suite not yet implemented"