diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 25bc69c..7441eec 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -14,9 +14,10 @@ on:
 
 env:
   # Common versions
-  GO_VERSION: '1.21.3'
-  GOLANGCI_VERSION: 'v1.54.2'
-  DOCKER_BUILDX_VERSION: 'v0.11.2'
+  GO_VERSION: '1.22.4'
+  GOLANGCI_VERSION: 'v1.59.1'
+  DOCKER_BUILDX_VERSION: 'v0.15.1'
+  PKL_VERSION: '0.26.0'
 
   # These environment variables are important to the Crossplane CLI install.sh
   # script. They determine what version it installs.
@@ -49,7 +50,7 @@ jobs:
           cache: false  # The golangci-lint action does its own caching.
 
       - name: Lint
-        uses: golangci/golangci-lint-action@v4
+        uses: golangci/golangci-lint-action@v6.0.1
         with:
           version: ${{ env.GOLANGCI_VERSION }}
 
@@ -64,6 +65,11 @@ jobs:
         with:
           go-version: ${{ env.GO_VERSION }}
 
+      - name: Install pkl
+        uses: pkl-community/setup-pkl@v0
+        with:
+          pkl-version: ${{ env.PKL_VERSION }}
+
       - name: Run Unit Tests
         run: go test -v -cover ./...
 
diff --git a/go.mod b/go.mod
index d0021cb..f8575fe 100644
--- a/go.mod
+++ b/go.mod
@@ -1,8 +1,6 @@
 module github.com/crossplane-contrib/function-pkl
 
-go 1.22.1
-
-toolchain go1.22.3
+go 1.22.4
 
 require (
 	github.com/alecthomas/kong v0.9.0
diff --git a/input/v1beta1/input.go b/input/v1beta1/input.go
index 8e22d61..e4911eb 100644
--- a/input/v1beta1/input.go
+++ b/input/v1beta1/input.go
@@ -25,7 +25,7 @@ import (
 // This isn't a custom resource, in the sense that we never install its CRD.
 // It is a KRM-like object, so we generate a CRD to describe its schema.
 
-// Input can be used to provide input to this Function.
+// Pkl struct can be used to provide input to this Function.
 // +kubebuilder:object:root=true
 // +kubebuilder:storageversion
 // +kubebuilder:resource:categories=crossplane
@@ -37,12 +37,13 @@ type Pkl struct {
 	Spec PklSpec `json:"spec,omitempty"`
 }
 
+// PklSpec specifies references for the function
 type PklSpec struct {
 	// +kubebuilder:validation:Enum=uri;inline;local
 	Type string `json:"type,omitempty"`
 
 	// Use URI Scheme to load Project/Package
-	Uri string `json:"uri,omitempty"`
+	URI string `json:"uri,omitempty"`
 	// Contains a stringified Pkl file
 	Inline string `json:"inline,omitempty"`
 
diff --git a/internal/extraresources.go b/internal/extraresources.go
deleted file mode 100644
index 46dfd57..0000000
--- a/internal/extraresources.go
+++ /dev/null
@@ -1,56 +0,0 @@
-/*
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-	http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package internal
-
-import (
-	fnv1beta1 "github.com/crossplane/function-sdk-go/proto/v1beta1"
-)
-
-type ExtraResourceSelectors struct {
-	ExtraResources map[string]*ExtraResourceSelector `json:"extraResourceSelectors,omitempty"`
-}
-
-func (e *ExtraResourceSelectors) ToResourceSelectors() map[string]*fnv1beta1.ResourceSelector {
-	out := map[string]*fnv1beta1.ResourceSelector{}
-	for name, extraResourceSelector := range e.ExtraResources {
-		out[name] = extraResourceSelector.ToResourceSelector()
-	}
-	return out
-}
-
-type ExtraResourceSelector struct {
-	ApiVersion  string            `json:"apiVersion"`
-	Kind        string            `json:"kind"`
-	MatchLabels map[string]string `json:"matchLabels,omitempty"`
-	Name        string            `json:"name,omitempty"`
-}
-
-func (e *ExtraResourceSelector) ToResourceSelector() *fnv1beta1.ResourceSelector {
-	out := &fnv1beta1.ResourceSelector{
-		ApiVersion: e.ApiVersion,
-		Kind:       e.Kind,
-	}
-	if len(e.MatchLabels) == 0 {
-		out.Match = &fnv1beta1.ResourceSelector_MatchName{
-			MatchName: e.Name,
-		}
-		return out
-	}
-
-	out.Match = &fnv1beta1.ResourceSelector_MatchLabels{
-		MatchLabels: &fnv1beta1.MatchLabels{Labels: e.MatchLabels},
-	}
-	return out
-}
diff --git a/internal/function/fn.go b/internal/function/fn.go
index 1ad03d7..9a99906 100644
--- a/internal/function/fn.go
+++ b/internal/function/fn.go
@@ -12,22 +12,25 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+// Package function package handles the gRPC calls
 package function
 
 import (
 	"context"
-	"google.golang.org/protobuf/types/known/durationpb"
 
 	"github.com/apple/pkl-go/pkl"
-	"github.com/crossplane-contrib/function-pkl/input/v1beta1"
-	"github.com/crossplane-contrib/function-pkl/internal/helper"
-	"github.com/crossplane-contrib/function-pkl/internal/pkl/reader"
+	"google.golang.org/protobuf/types/known/durationpb"
+	"sigs.k8s.io/yaml"
+
 	"github.com/crossplane/crossplane-runtime/pkg/errors"
 	"github.com/crossplane/crossplane-runtime/pkg/logging"
 	fnv1beta1 "github.com/crossplane/function-sdk-go/proto/v1beta1"
 	"github.com/crossplane/function-sdk-go/request"
 	"github.com/crossplane/function-sdk-go/response"
-	"sigs.k8s.io/yaml"
+
+	"github.com/crossplane-contrib/function-pkl/input/v1beta1"
+	"github.com/crossplane-contrib/function-pkl/internal/helper"
+	"github.com/crossplane-contrib/function-pkl/internal/pkl/reader"
 )
 
 // Function returns whatever response you ask it to.
@@ -90,8 +93,7 @@ func (f *Function) RunFunction(ctx context.Context, req *fnv1beta1.RunFunctionRe
 		return rsp, nil
 	}
 	defer func(evaluator pkl.Evaluator) {
-		err := evaluator.Close()
-		if err != nil {
+		if err := evaluator.Close(); err != nil {
 			f.Log.Info("evaluator could not be closed correctly:", err)
 		}
 	}(evaluator)
@@ -137,10 +139,10 @@ func convertExtraResources(extraResources map[string]*helper.ResourceSelector) m
 	out := make(map[string]*fnv1beta1.ResourceSelector)
 	for name, fixedrs := range extraResources {
 		rs := &fnv1beta1.ResourceSelector{
-			ApiVersion: fixedrs.ApiVersion,
+			ApiVersion: fixedrs.APIVersion,
 			Kind:       fixedrs.Kind,
 		}
-		if fixedrs.Match.MatchLabels != nil && len(fixedrs.Match.MatchLabels.Labels) > 0 {
+		if fixedrs.Match.MatchLabels != nil && len(fixedrs.Match.MatchLabels.GetLabels()) > 0 {
 			rs.Match = &fnv1beta1.ResourceSelector_MatchLabels{
 				MatchLabels: &fnv1beta1.MatchLabels{
 					Labels: fixedrs.Match.MatchLabels.GetLabels(),
@@ -159,10 +161,10 @@ func convertExtraResources(extraResources map[string]*helper.ResourceSelector) m
 func getModuleSource(pklSpec v1beta1.PklSpec) (*pkl.ModuleSource, error) {
 	switch pklSpec.Type {
 	case "uri":
-		if pklSpec.Uri == "" {
+		if pklSpec.URI == "" {
 			return nil, errors.New("manifest type is uri but uri is empty")
 		}
-		return pkl.UriSource(pklSpec.Uri), nil
+		return pkl.UriSource(pklSpec.URI), nil
 
 	case "inline":
 		if pklSpec.Inline == "" {
diff --git a/internal/function/fn_test.go b/internal/function/fn_test.go
index 58253b5..7dcb3d3 100644
--- a/internal/function/fn_test.go
+++ b/internal/function/fn_test.go
@@ -21,7 +21,6 @@ import (
 	"testing"
 
 	"github.com/apple/pkl-go/pkl"
-	"github.com/crossplane-contrib/function-pkl/input/v1beta1"
 	"github.com/google/go-cmp/cmp"
 	"github.com/google/go-cmp/cmp/cmpopts"
 	"google.golang.org/protobuf/testing/protocmp"
@@ -30,6 +29,8 @@ import (
 	"github.com/crossplane/crossplane-runtime/pkg/logging"
 	fnv1beta1 "github.com/crossplane/function-sdk-go/proto/v1beta1"
 	"github.com/crossplane/function-sdk-go/resource"
+
+	"github.com/crossplane-contrib/function-pkl/input/v1beta1"
 )
 
 var (
@@ -181,8 +182,7 @@ func TestRunFunction(t *testing.T) {
 		t.Run(name, func(t *testing.T) {
 			evaluatorManager := pkl.NewEvaluatorManager()
 			defer func(evaluatorManager pkl.EvaluatorManager) {
-				err := evaluatorManager.Close()
-				if err != nil {
+				if err := evaluatorManager.Close(); err != nil {
 					t.Error(err)
 				}
 			}(evaluatorManager)
diff --git a/internal/helper/composition.go b/internal/helper/composition.go
index 2816207..a651d5d 100644
--- a/internal/helper/composition.go
+++ b/internal/helper/composition.go
@@ -12,34 +12,40 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+// Package helper contains hacky alternative implementations of resources that would otherwise not be able to be converted to yaml
 package helper
 
 import fnv1beta1 "github.com/crossplane/function-sdk-go/proto/v1beta1"
 
+// CompositionRequest is a drop-in for RunFunctionRequest to replace ExtraResources
 type CompositionRequest struct {
 	*fnv1beta1.RunFunctionRequest
 
 	ExtraResources map[string]*fnv1beta1.Resources `protobuf:"bytes,6,rep,name=extra_resources,json=extraResources,proto3" json:"extraResources,omitempty" protobuf_key:"bytes,1,opt,name=key,proto3" protobuf_val:"bytes,2,opt,name=value,proto3"`
 }
 
+// CompositionResponse is a drop-in for RunFunctionResponse to replace Requirements
 type CompositionResponse struct {
 	fnv1beta1.RunFunctionResponse
 
 	Requirements *Requirements `json:"requirements,omitempty"`
 }
 
+// Requirements is a drop-in for the version provided by fnv1beta1
 type Requirements struct {
-	//fnv1beta1.Requirements
+	// fnv1beta1.Requirements
 
 	ExtraResources map[string]*ResourceSelector `protobuf:"bytes,1,rep,name=extra_resources,json=extraResources,proto3" json:"extraResources,omitempty" protobuf_key:"bytes,1,opt,name=key,proto3" protobuf_val:"bytes,2,opt,name=value,proto3"`
 }
 
+// ResourceSelector allows to select Kubernetes Resources
 type ResourceSelector struct {
-	ApiVersion string `protobuf:"bytes,1,opt,name=api_version,json=apiVersion,proto3" json:"apiVersion,omitempty"`
+	APIVersion string `protobuf:"bytes,1,opt,name=api_version,json=apiVersion,proto3" json:"apiVersion,omitempty"`
 	Kind       string `protobuf:"bytes,2,opt,name=kind,proto3" json:"kind,omitempty"`
 	Match      Match  `json:"match,omitempty"`
 }
 
+// Match specifies the method used for the Lookup
 type Match struct {
 	MatchName   string                 `protobuf:"bytes,3,opt,name=match_name,json=matchName,proto3,oneof" json:"matchName,omitempty"`
 	MatchLabels *fnv1beta1.MatchLabels `protobuf:"bytes,4,opt,name=match_labels,json=matchLabels,proto3,oneof" json:"matchLabels,omitempty"`
diff --git a/internal/pkl/reader/crossplane_reader.go b/internal/pkl/reader/crossplane_reader.go
index 4900315..f83b973 100644
--- a/internal/pkl/reader/crossplane_reader.go
+++ b/internal/pkl/reader/crossplane_reader.go
@@ -12,6 +12,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+// Package reader Contains Pkl Custom Readers
 package reader
 
 import (
@@ -20,11 +21,14 @@ import (
 	"net/url"
 
 	"github.com/apple/pkl-go/pkl"
-	"github.com/crossplane-contrib/function-pkl/internal/helper"
-	"github.com/crossplane/function-sdk-go/logging"
 	"sigs.k8s.io/yaml"
+
+	"github.com/crossplane/function-sdk-go/logging"
+
+	"github.com/crossplane-contrib/function-pkl/internal/helper"
 )
 
+// CrossplaneReader implements the "crossplane" scheme
 type CrossplaneReader struct {
 	Request      *helper.CompositionRequest
 	ReaderScheme string
@@ -32,14 +36,17 @@ type CrossplaneReader struct {
 	Ctx          context.Context
 }
 
+// Scheme implements the https://pkg.go.dev/github.com/apple/pkl-go/pkl#Reader interface
 func (f *CrossplaneReader) Scheme() string {
 	return f.ReaderScheme
 }
 
+// IsGlobbable implements https://pkg.go.dev/github.com/apple/pkl-go/pkl#Reader
 func (f *CrossplaneReader) IsGlobbable() bool {
 	return false
 }
 
+// HasHierarchicalUris implements https://pkg.go.dev/github.com/apple/pkl-go/pkl#Reader
 func (f *CrossplaneReader) HasHierarchicalUris() bool {
 	return false
 }
@@ -49,7 +56,7 @@ func (f *CrossplaneReader) HasHierarchicalUris() bool {
 // available values.
 //
 // This method is only called if it is hierarchical and local, or if it is globbable.
-func (f *CrossplaneReader) ListElements(url url.URL) ([]pkl.PathElement, error) {
+func (f *CrossplaneReader) ListElements(_ url.URL) ([]pkl.PathElement, error) {
 	out := []pkl.PathElement{
 		pkl.NewPathElement("request", false),
 	}
@@ -62,17 +69,12 @@ type crossplaneModuleReader struct {
 	*CrossplaneReader
 }
 
+// IsLocal implements https://pkg.go.dev/github.com/apple/pkl-go/pkl#ModuleReader
 func (f crossplaneModuleReader) IsLocal() bool {
 	return true
 }
 
-var evaluatorManager pkl.EvaluatorManager = pkl.NewEvaluatorManager()
-
-// TODO find better solution
-func Close() error {
-	return evaluatorManager.Close()
-}
-
+// WithCrossplane activates the CrossplaneReader for the Evaluator
 var WithCrossplane = func(crossplaneReader *CrossplaneReader) func(opts *pkl.EvaluatorOptions) {
 	return func(opts *pkl.EvaluatorOptions) {
 		reader := crossplaneReader
@@ -81,6 +83,7 @@ var WithCrossplane = func(crossplaneReader *CrossplaneReader) func(opts *pkl.Eva
 	}
 }
 
+// BaseRead contains the business logic of what happens when the scheme gets a request
 func (f *CrossplaneReader) BaseRead(url url.URL) ([]byte, error) {
 	switch url.Opaque {
 	case "request":
@@ -96,7 +99,7 @@ func (f *CrossplaneReader) BaseRead(url url.URL) ([]byte, error) {
 	}
 }
 
-// Expects an URL like /observed/composition/resource and evaluates the RunFunctionRequest for the state of the desired field and returns it as a pkl file
+// Read Expects a URL like /observed/composition/resource and evaluates the RunFunctionRequest for the state of the desired field and returns it as a pkl file
 func (f crossplaneModuleReader) Read(url url.URL) (string, error) {
 	out, err := f.BaseRead(url)
 	if err != nil {
@@ -111,6 +114,7 @@ type crossplaneResourceReader struct {
 	*CrossplaneReader
 }
 
+// Read implements https://pkg.go.dev/github.com/apple/pkl-go/pkl#ResourceReader
 func (f crossplaneResourceReader) Read(url url.URL) ([]byte, error) {
 	out, err := f.BaseRead(url)
 	if err != nil {
diff --git a/main.go b/main.go
index d092e81..7331bb7 100644
--- a/main.go
+++ b/main.go
@@ -22,7 +22,6 @@ import (
 	"github.com/crossplane/function-sdk-go"
 
 	fn "github.com/crossplane-contrib/function-pkl/internal/function"
-	"github.com/crossplane-contrib/function-pkl/internal/pkl/reader"
 )
 
 // CLI of this Function.
@@ -43,8 +42,11 @@ func (c *CLI) Run() error {
 	}
 
 	evaluatorManager := pkl.NewEvaluatorManager()
-	defer evaluatorManager.Close()
-	defer reader.Close()
+	defer func(evaluatorManager pkl.EvaluatorManager) {
+		if err := evaluatorManager.Close(); err != nil {
+			log.Info("error closing evaluatorManager", err)
+		}
+	}(evaluatorManager)
 
 	return function.Serve(&fn.Function{Log: log, EvaluatorManager: evaluatorManager},
 		function.Listen(c.Network, c.Address),