diff --git a/.drone.yml b/.drone.yml
index dc8c6cf..87bcda3 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -14,9 +14,11 @@ steps:
 - name: staticcheck
   pull: always
   image: golang:1.19
+  environment:
+    GO111MODULE: "on" # Explicitly enable Go modules
   commands:
-  - go get honnef.co/go/tools/cmd/staticcheck
-  - go run honnef.co/go/tools/cmd/staticcheck ./...
+  - go install honnef.co/go/tools/cmd/staticcheck@v0.4.3
+  - staticcheck ./...
   volumes:
   - name: gopath
     path: /go
diff --git a/go.mod b/go.mod
index 47c2603..550108f 100644
--- a/go.mod
+++ b/go.mod
@@ -4,11 +4,19 @@ go 1.19
 
 require (
 	github.com/sirupsen/logrus v1.9.0
+	github.com/stretchr/testify v1.7.0
 	github.com/urfave/cli/v2 v2.23.6
 )
 
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)
+
 require (
 	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
+	github.com/harness/godotenv/v3 v3.0.1
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
 	github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 // indirect
 	golang.org/x/sys v0.0.0-20220731174439-a90be440212d // indirect
diff --git a/go.sum b/go.sum
index 3c51b04..e4865a2 100644
--- a/go.sum
+++ b/go.sum
@@ -3,6 +3,8 @@ github.com/cpuguy83/go-md2man/v2 v2.0.2/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46t
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/harness/godotenv/v3 v3.0.1 h1:7QPEOkpx6SLLrYRRzPBp50d6c0XIxq721iqoFxbz1Bs=
+github.com/harness/godotenv/v3 v3.0.1/go.mod h1:UIXXJtTM7NkSYMYknHYOO2d8BfDlAWMYZRuRsXcDDR0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
@@ -12,10 +14,6 @@ github.com/sirupsen/logrus v1.9.0/go.mod h1:naHLuLoDiP4jHNo9R0sCBMtWGeIprob74mVs
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/urfave/cli/v2 v2.11.1 h1:UKK6SP7fV3eKOefbS87iT9YHefv7iB/53ih6e+GNAsE=
-github.com/urfave/cli/v2 v2.11.1/go.mod h1:f8iq5LtQ/bLxafbdBSLPPNsgaW0l/2fYYEHhAyPlwvo=
-github.com/urfave/cli/v2 v2.23.5 h1:xbrU7tAYviSpqeR3X4nEFWUdB/uDZ6DE+HxmRU7Xtyw=
-github.com/urfave/cli/v2 v2.23.5/go.mod h1:GHupkWPMM0M/sj1a2b4wUrWBPzazNrIjouW6fmdJLxc=
 github.com/urfave/cli/v2 v2.23.6 h1:iWmtKD+prGo1nKUtLO0Wg4z9esfBM4rAV4QRLQiEmJ4=
 github.com/urfave/cli/v2 v2.23.6/go.mod h1:GHupkWPMM0M/sj1a2b4wUrWBPzazNrIjouW6fmdJLxc=
 github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 h1:bAn7/zixMGCfxrRTfdpNzjtPYqr8smhKouy9mxVdGPU=
@@ -23,6 +21,8 @@ github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673/go.mod h1:N3UwUGtsr
 golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220731174439-a90be440212d h1:Sv5ogFZatcgIMMtBSTTAgMYsicp25MXBubjXNDKwm80=
 golang.org/x/sys v0.0.0-20220731174439-a90be440212d/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/harness/variables.go b/harness/variables.go
new file mode 100644
index 0000000..dc5e640
--- /dev/null
+++ b/harness/variables.go
@@ -0,0 +1,213 @@
+package harness
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	v3 "github.com/harness/godotenv/v3"
+)
+
+const (
+	// ErrorMessageKey is the key used to retrieve or store the error message content.
+	ErrorMessageKey = "ERROR_MESSAGE"
+
+	// ErrorCodeKey is the key used to identify the specific error code associated with an error.
+	ErrorCodeKey = "ERROR_CODE"
+
+	// ErrorCategoryKey is the key used to classify the category of the error, which can help in grouping similar types of errors.
+	ErrorCategoryKey = "ERROR_CATEGORY"
+
+	// MetadataFile is the key for the file that stores metadata associated with an error, such as details about the error's source or context.
+	MetadataFile = "ERROR_METADATA_FILE"
+
+	// DroneOutputFile is the key for the file where outputs can be exported and utilized in the subsequent steps in Harness CI pipeline.
+	DroneOutputFile = "DRONE_OUTPUT"
+
+	// HarnessOutputSecretFile is the key for the file where secrets can be exported and utilized in the subsequent steps in Harness CI pipeline.
+	HarnessOutputSecretFile = "HARNESS_OUTPUT_SECRET_FILE"
+)
+
+// SetSecret sets a new secret by adding it to the HARNESS_OUTPUT_SECRET_FILE file
+func SetSecret(name, value string) error {
+	return UpdateOrRemoveKeyValue(HarnessOutputSecretFile, name, value, false)
+}
+
+// UpdateSecret overwrites the value of an existing secret.
+func UpdateSecret(name, value string) error {
+	return UpdateOrRemoveKeyValue(HarnessOutputSecretFile, name, value, false)
+}
+
+// DeleteSecret removes a secret from the file entirely.
+func DeleteSecret(name string) error {
+	return UpdateOrRemoveKeyValue(HarnessOutputSecretFile, name, "", true)
+}
+
+// SetOutput sets a new secret by adding it to the DRONE_OUTPUT file
+func SetOutput(name, value string) error {
+	return UpdateOrRemoveKeyValue(DroneOutputFile, name, value, false)
+}
+
+// UpdateOutput overwrites the value of an existing output.
+func UpdateOutput(name, value string) error {
+	return UpdateOrRemoveKeyValue(DroneOutputFile, name, value, false)
+}
+
+// DeleteOutput removes an output from the file entirely.
+func DeleteOutput(name string) error {
+	return UpdateOrRemoveKeyValue(DroneOutputFile, name, "", true)
+}
+
+// SetErrorMetadata sets the error message, error code, and error category, writing them to the CI_ERROR_METADATA file
+func SetErrorMetadata(message, code, category string) error {
+	// Write the error message
+	if err := UpdateOrRemoveKeyValue(MetadataFile, ErrorMessageKey, message, false); err != nil {
+		return err
+	}
+
+	// Write the error code
+	if err := UpdateOrRemoveKeyValue(MetadataFile, ErrorCodeKey, code, false); err != nil {
+		return err
+	}
+
+	// Write the error category
+	if err := UpdateOrRemoveKeyValue(MetadataFile, ErrorCategoryKey, category, false); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// UpdateOrRemoveKeyValue updates or deletes a key-value pair in the specified file.
+func UpdateOrRemoveKeyValue(envVar, key, newValue string, deleteKey bool) error {
+	filePath := os.Getenv(envVar)
+	if filePath == "" {
+		return fmt.Errorf("environment variable %s is not set", envVar)
+	}
+
+	// Ensure the file exists before reading
+	if _, err := os.Stat(filePath); os.IsNotExist(err) {
+		_, err := os.OpenFile(filePath, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0644)
+		if err != nil {
+			return fmt.Errorf("failed to create file: %w", err)
+		}
+	}
+
+	// Trim trailing newline characters from newValue
+	newValue = strings.TrimRight(newValue, "\n")
+
+	ext := strings.ToLower(filepath.Ext(filePath))
+
+	if ext == ".env" {
+		// Use godotenv for .env files
+		data, err := v3.Read(filePath)
+		if err != nil {
+			return fmt.Errorf("failed to parse .env file: %w", err)
+		}
+
+		if deleteKey {
+			delete(data, key)
+		} else {
+			data[key] = newValue
+		}
+
+		err = v3.Write(data, filePath)
+		if err != nil {
+			return fmt.Errorf("failed to write .env file: %w", err)
+		}
+	} else {
+		// For .out files, process manually
+		// For .out files, check for multiline values
+		if strings.Contains(newValue, "\n") {
+			return fmt.Errorf("multiline values are not allowed for key %s in .out file", key)
+		}
+
+		lines, err := ReadLines(filePath)
+		if err != nil {
+			return fmt.Errorf("failed to read file: %w", err)
+		}
+
+		var updatedLines []string
+		found := false
+		for _, line := range lines {
+			k, v := ParseKeyValue(line, ext)
+			if k == key {
+				found = true
+				if deleteKey {
+					continue
+				}
+				updatedLines = append(updatedLines, FormatKeyValue(k, newValue, ext))
+			} else {
+				updatedLines = append(updatedLines, FormatKeyValue(k, v, ext))
+			}
+		}
+
+		if !found && !deleteKey {
+			updatedLines = append(updatedLines, FormatKeyValue(key, newValue, ext))
+		}
+
+		err = WriteLines(filePath, updatedLines)
+		if err != nil {
+			return fmt.Errorf("failed to write file: %w", err)
+		}
+	}
+
+	return nil
+}
+
+// ReadLines reads lines from a file and returns them as a slice of strings.
+func ReadLines(filename string) ([]string, error) {
+	file, err := os.Open(filename)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	var lines []string
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		lines = append(lines, scanner.Text())
+	}
+	return lines, scanner.Err()
+}
+
+// WriteLines writes a slice of strings to a file, each string being written to a new line.
+func WriteLines(filename string, lines []string) error {
+	file, err := os.Create(filename)
+	if err != nil {
+		return fmt.Errorf("failed to create file: %w", err)
+	}
+	defer file.Close()
+
+	for _, line := range lines {
+		_, err := file.WriteString(line + "\n")
+		if err != nil {
+			return fmt.Errorf("failed to write to file: %w", err)
+		}
+	}
+	return nil
+}
+
+// ParseKeyValue parses a key-value pair from a string and returns the key and value.
+func ParseKeyValue(line, ext string) (string, string) {
+	if ext == ".out" {
+		parts := strings.Fields(line)
+		if len(parts) > 1 {
+			return strings.TrimSpace(parts[0]), strings.TrimSpace(strings.Join(parts[1:], " "))
+		}
+		return strings.TrimSpace(parts[0]), ""
+	}
+	// .env is handled by godotenv, so this is not used for .env files
+	return "", ""
+}
+
+// FormatKeyValue handles formatting for .env and .out files.
+func FormatKeyValue(key, value, ext string) string {
+	if ext == ".out" {
+		return fmt.Sprintf("%s %s", key, value)
+	}
+	// For .env files, use godotenv directly; this function won't apply
+	return ""
+}
diff --git a/harness/variables_test.go b/harness/variables_test.go
new file mode 100644
index 0000000..a6be218
--- /dev/null
+++ b/harness/variables_test.go
@@ -0,0 +1,218 @@
+package harness
+
+import (
+	"os"
+	"testing"
+
+	v3 "github.com/harness/godotenv/v3"
+	"github.com/stretchr/testify/assert"
+)
+
+// Helper function to create the .env file with the given content
+func createEnvFile(t *testing.T, filePath string, content map[string]string) error {
+	file, err := os.Create(filePath)
+	if err != nil {
+		t.Fatalf("Failed to create file: %v", err)
+		return err
+	}
+	defer file.Close()
+
+	for key, value := range content {
+		_, err := file.WriteString(key + "=" + value + "\n")
+		if err != nil {
+			t.Fatalf("Failed to write to file: %v", err)
+			return err
+		}
+	}
+
+	return nil
+}
+
+// Helper function to create an output file (.out) with the given content
+func createOutFile(t *testing.T, filePath string, content []string) error {
+	file, err := os.Create(filePath)
+	if err != nil {
+		t.Fatalf("Failed to create file: %v", err)
+		return err
+	}
+	defer file.Close()
+
+	// Write the content to the .out file manually
+	for _, line := range content {
+		_, err := file.WriteString(line + "\n")
+		if err != nil {
+			t.Fatalf("Failed to write to file: %v", err)
+			return err
+		}
+	}
+	return nil
+}
+
+// Test Set, Update, and Delete functions for .env files
+func TestSetUpdateDeleteEnvFile(t *testing.T) {
+	// Set the environment variable to point to the test.env file
+	envFilePath := "test.env"
+	os.Setenv("HARNESS_OUTPUT_SECRET_FILE", envFilePath)
+
+	// Setup: Create the .env file at the path specified by HARNESS_OUTPUT_SECRET_FILE
+	envContent := map[string]string{
+		"KEY1": "value1",
+		"KEY2": "value2",
+	}
+	err := createEnvFile(t, envFilePath, envContent)
+	assert.NoError(t, err)
+
+	// Defer file removal after the test completes
+	defer os.Remove(envFilePath)
+
+	// Set a new key-value pair
+	err = SetSecret("KEY3", "value3")
+	assert.NoError(t, err)
+
+	// Update an existing key-value pair
+	err = UpdateSecret("KEY1", "new_value1")
+	assert.NoError(t, err)
+
+	// Delete an existing key
+	err = DeleteSecret("KEY2")
+	assert.NoError(t, err)
+
+	// Read the file content and verify the changes
+	data, err := v3.Read(envFilePath)
+	assert.NoError(t, err)
+
+	// Assertions
+	assert.Equal(t, "new_value1", data["KEY1"])
+	assert.Equal(t, "value3", data["KEY3"])
+	assert.NotContains(t, data, "KEY2")
+
+	// Clean up
+	defer os.Unsetenv("HARNESS_OUTPUT_SECRET_FILE")
+}
+
+// Test Set, Update, and Delete functions for .out files (single-line values)
+func TestSetUpdateDeleteOutFile(t *testing.T) {
+	// Set the environment variable to point to the test.out file
+	outFilePath := "test.out"
+	os.Setenv("DRONE_OUTPUT", outFilePath)
+
+	// Setup: Create the .out file at the path specified by DRONE_OUTPUT
+	outContent := []string{
+		"KEY1 value1",
+		"KEY2 value2",
+	}
+	err := createOutFile(t, outFilePath, outContent)
+	assert.NoError(t, err)
+
+	// Defer file removal after the test completes
+	defer os.Remove(outFilePath)
+
+	// Set a new key-value pair
+	err = SetOutput("KEY3", "value3")
+	assert.NoError(t, err)
+
+	// Update an existing key-value pair
+	err = UpdateOutput("KEY1", "new_value1")
+	assert.NoError(t, err)
+
+	// Delete an existing key
+	err = DeleteOutput("KEY2")
+	assert.NoError(t, err)
+
+	// Verify changes
+	lines, err := ReadLines(outFilePath)
+	assert.NoError(t, err)
+
+	// Assertions
+	assert.Contains(t, lines, "KEY1 new_value1")
+	assert.Contains(t, lines, "KEY3 value3")
+	assert.NotContains(t, lines, "KEY2")
+
+	// Clean up
+	defer os.Unsetenv("DRONE_OUTPUT")
+}
+
+// Test Set, Update, and Delete functions for multiline values in .env file
+func TestSetUpdateDeleteMultilineEnvFile(t *testing.T) {
+	// Set the environment variable to point to the test.env file
+	envFilePath := "test.env"
+	os.Setenv("HARNESS_OUTPUT_SECRET_FILE", envFilePath)
+
+	// Setup: Create a temporary .env file with multiline value for a key
+	envContent := map[string]string{}
+	err := createEnvFile(t, envFilePath, envContent)
+	assert.NoError(t, err)
+
+	// Defer file removal after the test completes
+	defer os.Remove(envFilePath)
+
+	// Set a new multiline value
+	err = SetSecret("KEY1", "line1\nline2\nline3")
+	assert.NoError(t, err)
+
+	// Verify the multiline update
+	data, err := v3.Read(envFilePath)
+	assert.NoError(t, err)
+	assert.Equal(t, "line1\nline2\nline3", data["KEY1"])
+
+	err = UpdateSecret("KEY1", "line4\nline5\nline6")
+	assert.NoError(t, err)
+
+	// Verify the multiline update
+	data, err = v3.Read(envFilePath)
+	assert.NoError(t, err)
+	assert.Equal(t, "line4\nline5\nline6", data["KEY1"])
+
+	// Delete the key
+	err = DeleteSecret("KEY1")
+	assert.NoError(t, err)
+
+	// Verify deletion
+	data, err = v3.Read(envFilePath)
+	assert.NoError(t, err)
+	assert.NotContains(t, data, "KEY1")
+
+	// Clean up
+	defer os.Unsetenv("HARNESS_OUTPUT_SECRET_FILE")
+}
+
+// Test invalid cases for setting a secret in .out (should not allow multiline)
+func TestSetInvalidMultilineOut(t *testing.T) {
+	// Set the environment variable to point to the test.out file
+	outFilePath := "test.out"
+	os.Setenv("DRONE_OUTPUT", outFilePath)
+
+	// Setup: Create a temporary .out file
+	outContent := []string{
+		"KEY1 value1",
+		"KEY2 value2",
+	}
+	err := createOutFile(t, outFilePath, outContent)
+	assert.NoError(t, err)
+
+	// Defer file removal after the test completes
+	defer os.Remove(outFilePath)
+
+	// Attempt to set a multiline value (should fail)
+	err = SetOutput("KEY3", "line1\nline2")
+	assert.Error(t, err)
+
+	// Verify the content did not change
+	lines, err := ReadLines(outFilePath)
+	assert.NoError(t, err)
+
+	// Assertions
+	assert.Contains(t, lines, "KEY1 value1")
+	assert.Contains(t, lines, "KEY2 value2")
+
+	// Clean up
+	defer os.Unsetenv("DRONE_OUTPUT")
+}
+
+// Test that the functions return the appropriate error when the file does not exist
+func TestFileNotExistError(t *testing.T) {
+	// Attempt to set a value when the .env file is missing
+	err := SetSecret("KEY1", "value1")
+	assert.Error(t, err)
+	assert.Contains(t, err.Error(), "environment variable HARNESS_OUTPUT_SECRET_FILE is not set")
+}