diff --git a/Package.swift b/Package.swift
index 14bd36aea..5f086c71b 100644
--- a/Package.swift
+++ b/Package.swift
@@ -171,7 +171,7 @@ let package = Package(
     .package(url: "https://github.com/apple/swift-system", from: "1.4.0"),
     .package(url: "https://github.com/apple/swift-log", from: "1.2.0"),
     .package(url: "https://github.com/apple/swift-collections", from: "1.3.0"), // primarily for ordered collections
-    .package(url: "https://github.com/swiftlang/swift-subprocess.git", "0.4.0"..<"0.5.0", traits: ["SubprocessFoundation"]),
+    .package(url: "https://github.com/swiftlang/swift-subprocess.git", "1.0.0"..<"2.0.0", traits: ["SubprocessFoundation"]),
 
     // Benchmarking
     .package(url: "https://github.com/ordo-one/package-benchmark", .upToNextMajor(from: "1.4.0")),
diff --git a/Sources/StaticBuildConfigPluginExecutable/StaticBuildConfigPluginExecutable.swift b/Sources/StaticBuildConfigPluginExecutable/StaticBuildConfigPluginExecutable.swift
index 52a1d07be..47a0fb33f 100644
--- a/Sources/StaticBuildConfigPluginExecutable/StaticBuildConfigPluginExecutable.swift
+++ b/Sources/StaticBuildConfigPluginExecutable/StaticBuildConfigPluginExecutable.swift
@@ -37,7 +37,8 @@ import SwiftIfConfig
       output: .data(limit: 65536),
       error: .string(limit: 65536)
     )
-    if let error = result.standardError, !error.isEmpty {
+    let error = result.standardError
+    if !error.isEmpty {
       fatalError(error)
     }
     return result.standardOutput
diff --git a/Sources/SwiftJavaTool/Commands/JavaCallbacksBuildCommand.swift b/Sources/SwiftJavaTool/Commands/JavaCallbacksBuildCommand.swift
index 1182e3c08..1b4d84721 100644
--- a/Sources/SwiftJavaTool/Commands/JavaCallbacksBuildCommand.swift
+++ b/Sources/SwiftJavaTool/Commands/JavaCallbacksBuildCommand.swift
@@ -269,8 +269,8 @@ private func runSubprocess(
     .path(FilePath(executable)),
     arguments: .init(arguments),
     environment: environment,
-    output: FileDescriptorOutput.standardOutput,
-    error: FileDescriptorOutput.standardError,
+    output: FileDescriptorOutput.currentStandardOutput,
+    error: FileDescriptorOutput.currentStandardError,
   )
   guard result.terminationStatus.isSuccess else {
     throw JavaCallbacksBuildError(
diff --git a/Sources/SwiftJavaToolLib/JavaDependencyResolver.swift b/Sources/SwiftJavaToolLib/JavaDependencyResolver.swift
index 70d831c3c..f5869c4db 100644
--- a/Sources/SwiftJavaToolLib/JavaDependencyResolver.swift
+++ b/Sources/SwiftJavaToolLib/JavaDependencyResolver.swift
@@ -141,8 +141,8 @@ public struct JavaDependencyResolver {
       error: .string(limit: Int.max, encoding: UTF8.self)
     )
 
-    let outString = process.standardOutput ?? ""
-    let errString = process.standardError ?? ""
+    let outString = process.standardOutput
+    let errString = process.standardError
 
     if let found = outString.split(separator: "\n").first(where: { $0.hasPrefix(SwiftJavaClasspathPrefix) }) {
       return String(found.dropFirst(SwiftJavaClasspathPrefix.count))
diff --git a/Tests/SwiftJavaToolLibTests/CompileJavaTool.swift b/Tests/SwiftJavaToolLibTests/CompileJavaTool.swift
index 1fde8202a..c1f471d29 100644
--- a/Tests/SwiftJavaToolLibTests/CompileJavaTool.swift
+++ b/Tests/SwiftJavaToolLibTests/CompileJavaTool.swift
@@ -56,8 +56,8 @@ struct CompileJavaTool {
     )
 
     guard javacProcess.terminationStatus.isSuccess else {
-      let outString = javacProcess.standardOutput ?? ""
-      let errString = javacProcess.standardError ?? ""
+      let outString = javacProcess.standardOutput
+      let errString = javacProcess.standardError
       fatalError(
         "javac failed (\(javacProcess.terminationStatus));\nOUT: \(outString)\nERROR: \(errString)"
       )
@@ -104,8 +104,8 @@ struct CompileJavaTool {
     )
 
     guard javacProcess.terminationStatus.isSuccess else {
-      let outString = javacProcess.standardOutput ?? ""
-      let errString = javacProcess.standardError ?? ""
+      let outString = javacProcess.standardOutput
+      let errString = javacProcess.standardError
       fatalError(
         "javac '\(sourceFile)' failed (\(javacProcess.terminationStatus));\nOUT: \(outString)\nERROR: \(errString)"
       )
@@ -131,8 +131,8 @@ struct CompileJavaTool {
     )
 
     guard jarProcess.terminationStatus.isSuccess else {
-      let outString = jarProcess.standardOutput ?? ""
-      let errString = jarProcess.standardError ?? ""
+      let outString = jarProcess.standardOutput
+      let errString = jarProcess.standardError
       fatalError(
         "jar failed (\(jarProcess.terminationStatus));\nOUT: \(outString)\nERROR: \(errString)"
       )