diff --git a/Sources/GoogleAI/FunctionCalling.swift b/Sources/GoogleAI/FunctionCalling.swift
index 159c8b4..f723c3e 100644
--- a/Sources/GoogleAI/FunctionCalling.swift
+++ b/Sources/GoogleAI/FunctionCalling.swift
@@ -353,13 +353,14 @@ extension CodeExecution: Encodable {}
 
 extension ExecutableCode: Codable {}
 
-@available(iOS 15.0, macOS 11.0, macCatalyst 15.0, *)
 extension CodeExecutionResult.Outcome: Codable {
   public init(from decoder: any Decoder) throws {
     let value = try decoder.singleValueContainer().decode(String.self)
     guard let decodedOutcome = CodeExecutionResult.Outcome(rawValue: value) else {
-      Logging.default
-        .error("[GoogleGenerativeAI] Unrecognized Outcome with value \"\(value)\".")
+      if #available(iOS 15.0, macOS 11.0, macCatalyst 15.0, *) {
+        Logging.default
+          .error("[GoogleGenerativeAI] Unrecognized Outcome with value \"\(value)\".")
+      }
       self = .unknown
       return
     }
@@ -368,7 +369,6 @@ extension CodeExecutionResult.Outcome: Codable {
   }
 }
 
-@available(iOS 15.0, macOS 11.0, macCatalyst 15.0, *)
 extension CodeExecutionResult: Codable {
   public init(from decoder: any Decoder) throws {
     let container = try decoder.container(keyedBy: CodingKeys.self)
diff --git a/Tests/GoogleAITests/CodeExecutionTests.swift b/Tests/GoogleAITests/CodeExecutionTests.swift
new file mode 100644
index 0000000..b504eab
--- /dev/null
+++ b/Tests/GoogleAITests/CodeExecutionTests.swift
@@ -0,0 +1,153 @@
+// Copyright 2024 Google LLC
+//
+// 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.
+
+import XCTest
+
+@testable import GoogleGenerativeAI
+
+final class CodeExecutionTests: XCTestCase {
+  let decoder = JSONDecoder()
+  let encoder = JSONEncoder()
+
+  let languageKey = "language"
+  let languageValue = "PYTHON"
+  let codeKey = "code"
+  let codeValue = "print('Hello, world!')"
+  let outcomeKey = "outcome"
+  let outcomeValue = "OUTCOME_OK"
+  let outputKey = "output"
+  let outputValue = "Hello, world!"
+
+  override func setUp() {
+    encoder.outputFormatting = .init(
+      arrayLiteral: .prettyPrinted, .sortedKeys, .withoutEscapingSlashes
+    )
+  }
+
+  func testEncodeCodeExecution() throws {
+    let jsonData = try encoder.encode(CodeExecution())
+
+    let json = try XCTUnwrap(String(data: jsonData, encoding: .utf8))
+    XCTAssertEqual(json, """
+    {
+
+    }
+    """)
+  }
+
+  func testDecodeExecutableCode() throws {
+    let expectedExecutableCode = ExecutableCode(language: languageValue, code: codeValue)
+    let json = """
+    {
+      "\(languageKey)": "\(languageValue)",
+      "\(codeKey)": "\(codeValue)"
+    }
+    """
+    let jsonData = try XCTUnwrap(json.data(using: .utf8))
+
+    let executableCode = try XCTUnwrap(decoder.decode(ExecutableCode.self, from: jsonData))
+
+    XCTAssertEqual(executableCode, expectedExecutableCode)
+  }
+
+  func testEncodeExecutableCode() throws {
+    let executableCode = ExecutableCode(language: languageValue, code: codeValue)
+
+    let jsonData = try encoder.encode(executableCode)
+
+    let json = try XCTUnwrap(String(data: jsonData, encoding: .utf8))
+    XCTAssertEqual(json, """
+    {
+      "\(codeKey)" : "\(codeValue)",
+      "\(languageKey)" : "\(languageValue)"
+    }
+    """)
+  }
+
+  func testDecodeCodeExecutionResultOutcome_ok() throws {
+    let expectedOutcome = CodeExecutionResult.Outcome.ok
+    let json = "\"\(outcomeValue)\""
+    let jsonData = try XCTUnwrap(json.data(using: .utf8))
+
+    let outcome = try XCTUnwrap(decoder.decode(CodeExecutionResult.Outcome.self, from: jsonData))
+
+    XCTAssertEqual(outcome, expectedOutcome)
+  }
+
+  func testDecodeCodeExecutionResultOutcome_unknown() throws {
+    let expectedOutcome = CodeExecutionResult.Outcome.unknown
+    let json = "\"OUTCOME_NEW_VALUE\""
+    let jsonData = try XCTUnwrap(json.data(using: .utf8))
+
+    let outcome = try XCTUnwrap(decoder.decode(CodeExecutionResult.Outcome.self, from: jsonData))
+
+    XCTAssertEqual(outcome, expectedOutcome)
+  }
+
+  func testEncodeCodeExecutionResultOutcome() throws {
+    let jsonData = try encoder.encode(CodeExecutionResult.Outcome.ok)
+
+    let json = try XCTUnwrap(String(data: jsonData, encoding: .utf8))
+    XCTAssertEqual(json, "\"\(outcomeValue)\"")
+  }
+
+  func testDecodeCodeExecutionResult() throws {
+    let expectedCodeExecutionResult = CodeExecutionResult(outcome: .ok, output: "Hello, world!")
+    let json = """
+    {
+      "\(outcomeKey)": "\(outcomeValue)",
+      "\(outputKey)": "\(outputValue)"
+    }
+    """
+    let jsonData = try XCTUnwrap(json.data(using: .utf8))
+
+    let codeExecutionResult = try XCTUnwrap(decoder.decode(
+      CodeExecutionResult.self,
+      from: jsonData
+    ))
+
+    XCTAssertEqual(codeExecutionResult, expectedCodeExecutionResult)
+  }
+
+  func testDecodeCodeExecutionResult_missingOutput() throws {
+    let expectedCodeExecutionResult = CodeExecutionResult(outcome: .deadlineExceeded, output: "")
+    let json = """
+    {
+      "\(outcomeKey)": "OUTCOME_DEADLINE_EXCEEDED"
+    }
+    """
+    let jsonData = try XCTUnwrap(json.data(using: .utf8))
+
+    let codeExecutionResult = try XCTUnwrap(decoder.decode(
+      CodeExecutionResult.self,
+      from: jsonData
+    ))
+
+    XCTAssertEqual(codeExecutionResult, expectedCodeExecutionResult)
+  }
+
+  func testEncodeCodeExecutionResult() throws {
+    let codeExecutionResult = CodeExecutionResult(outcome: .ok, output: outputValue)
+
+    let jsonData = try encoder.encode(codeExecutionResult)
+
+    let json = try XCTUnwrap(String(data: jsonData, encoding: .utf8))
+    XCTAssertEqual(json, """
+    {
+      "\(outcomeKey)" : "\(outcomeValue)",
+      "\(outputKey)" : "\(outputValue)"
+    }
+    """)
+  }
+}