Sequencer is working (minimal parsing)

internal/config/config.go

@@ -1,9 +1,13 @@
+
+
 package config
 
 import (
 	"fmt"
 	"os"
+	"regexp"
 	"strconv"
+	"strings"
 
 	"gopkg.in/yaml.v3"
 )
@@ -117,9 +121,12 @@ func Load(filename string) (*Config, error) {
 		return nil, fmt.Errorf("failed to read config file: %w", err)
 	}
 
+	// Expand environment variables in the raw YAML
+	expandedData := expandEnvVars(string(data))
+
 	// Parse the YAML
 	var config Config
-	if err := yaml.Unmarshal(data, &config); err != nil {
+	if err := yaml.Unmarshal([]byte(expandedData), &config); err != nil {
 		return nil, fmt.Errorf("failed to parse config file: %w", err)
 	}
 
@@ -129,6 +136,33 @@ func Load(filename string) (*Config, error) {
 	return &config, nil
 }
 
+// expandEnvVars expands ${VAR} and $VAR patterns in the given string
+func expandEnvVars(s string) string {
+	// Pattern to match ${VAR} and $VAR
+	envVarPattern := regexp.MustCompile(`\$\{([^}]+)\}|\$([A-Za-z_][A-Za-z0-9_]*)`)
+	
+	return envVarPattern.ReplaceAllStringFunc(s, func(match string) string {
+		var varName string
+		
+		// Handle ${VAR} format
+		if strings.HasPrefix(match, "${") && strings.HasSuffix(match, "}") {
+			varName = match[2 : len(match)-1]
+		} else if strings.HasPrefix(match, "$") {
+			// Handle $VAR format
+			varName = match[1:]
+		}
+		
+		// Get environment variable value
+		if value := os.Getenv(varName); value != "" {
+			return value
+		}
+		
+		// Return empty string if environment variable is not set
+		// This prevents invalid YAML when variables are missing
+		return ""
+	})
+}
+
 // OverrideWithEnv overrides configuration with environment variables
 func (c *Config) OverrideWithEnv() {
 	// Override RPC endpoint