diff --git a/Sources/ScipioKit/Executor.swift b/Sources/ScipioKit/Executor.swift
index 79094f62..80f65961 100644
--- a/Sources/ScipioKit/Executor.swift
+++ b/Sources/ScipioKit/Executor.swift
@@ -11,8 +11,19 @@ private actor ProcessOutputBuffer {
 
 @_spi(Internals)
 public protocol Executor {
+    /// Executes the command with the given arguments and environment variables.
+    ///
+    /// - Parameters:
+    ///   - arguments: Command-line arguments for the process.
+    ///   - environment: Complete set of environment variables for the process.
+    ///     If `nil`, the current environment is used.
+    ///     If non-nil, it **replaces** the entire environment.
+    ///     Use `ProcessInfo.processInfo.environment` to preserve existing values if needed.
+    ///
+    /// - Note:
+    ///   This does not merge with the existing environment.
     @discardableResult
-    func execute(_ arguments: [String]) async throws -> ExecutorResult
+    func execute(_ arguments: [String], environment: [String: String]?) async throws -> ExecutorResult
 }
 
 @_spi(Internals)
@@ -43,6 +54,11 @@ public protocol ExecutorResult: Sendable {
 }
 
 public extension Executor {
+    @discardableResult
+    func execute(_ arguments: [String]) async throws -> ExecutorResult {
+        try await execute(arguments, environment: nil)
+    }
+
     @discardableResult
     func execute(_ arguments: String...) async throws -> ExecutorResult {
         try await execute(arguments)
@@ -98,7 +114,7 @@ public struct ProcessExecutor<Decoder: ErrorDecoder>: Executor, Sendable {
 
     public var streamOutput: (@Sendable ([UInt8]) async -> Void)?
 
-    public func execute(_ arguments: [String]) async throws -> ExecutorResult {
+    public func execute(_ arguments: [String], environment: [String: String]?) async throws -> ExecutorResult {
         guard let executable = arguments.first, !executable.isEmpty else {
             throw ProcessExecutorError.executableNotFound
         }
@@ -108,7 +124,7 @@ public struct ProcessExecutor<Decoder: ErrorDecoder>: Executor, Sendable {
             throw ProcessExecutorError.executableNotFound
         }
 
-        let process = Foundation.Process()
+        let process = Process()
         let stdoutPipe = Pipe()
         let stderrPipe = Pipe()
 
@@ -117,6 +133,12 @@ public struct ProcessExecutor<Decoder: ErrorDecoder>: Executor, Sendable {
         process.standardOutput = stdoutPipe
         process.standardError = stderrPipe
 
+        // Completely replace the process environment if provided.
+        // If nil, the process inherits the current environment.
+        if let environment {
+            process.environment = environment
+        }
+
         let outputHandle = stdoutPipe.fileHandleForReading
         let errorHandle = stderrPipe.fileHandleForReading
 
diff --git a/Tests/ScipioKitTests/TestingExecutor.swift b/Tests/ScipioKitTests/TestingExecutor.swift
index 8c1d0bad..5a5a09f3 100644
--- a/Tests/ScipioKitTests/TestingExecutor.swift
+++ b/Tests/ScipioKitTests/TestingExecutor.swift
@@ -13,7 +13,7 @@ final class StubbableExecutor: Executor {
         calledArguments.count
     }
 
-    func execute(_ arguments: [String]) async throws -> ExecutorResult {
+    func execute(_ arguments: [String], environment: [String: String]?) async throws -> ExecutorResult {
         calledArguments.append(arguments)
         return try executeHook(arguments)
     }