diff --git a/ci/diagnose.js b/ci/diagnose.js
index 35919026b24..c7f90557686 100644
--- a/ci/diagnose.js
+++ b/ci/diagnose.js
@@ -506,8 +506,10 @@ function checkSupportedFrameworks (results, frameworks) {
       )
     }
 
-    for (const note of framework.notes || []) {
-      addResult(results, 'info', `${framework.name} capability note`, note)
+    if (framework.notes) {
+      for (const note of framework.notes) {
+        addResult(results, 'info', `${framework.name} capability note`, note)
+      }
     }
   }
 }
diff --git a/ci/test-optimization-validation/approval-artifacts.js b/ci/test-optimization-validation/approval-artifacts.js
index 0bcd843d32d..ac087d018de 100644
--- a/ci/test-optimization-validation/approval-artifacts.js
+++ b/ci/test-optimization-validation/approval-artifacts.js
@@ -154,10 +154,16 @@ function getCoveredFilesManifest (material) {
   }
   for (const executable of material.executables) {
     if (executable.path && executable.sha256) files.set(executable.path, executable.sha256)
-    for (const delegated of executable.delegated || []) files.set(delegated.path, delegated.sha256)
-    for (const entrypoint of executable.entrypoints || []) files.set(entrypoint.path, entrypoint.sha256)
+    if (executable.delegated) {
+      for (const delegated of executable.delegated) files.set(delegated.path, delegated.sha256)
+    }
+    if (executable.entrypoints) {
+      for (const entrypoint of executable.entrypoints) files.set(entrypoint.path, entrypoint.sha256)
+    }
+  }
+  if (material.projectFiles) {
+    for (const projectFile of material.projectFiles) files.set(projectFile.path, projectFile.sha256)
   }
-  for (const projectFile of material.projectFiles || []) files.set(projectFile.path, projectFile.sha256)
 
   return [...files]
     .sort(([left], [right]) => left.localeCompare(right))
diff --git a/ci/test-optimization-validation/approval.js b/ci/test-optimization-validation/approval.js
index 3ce0234edfa..4ab375e432f 100644
--- a/ci/test-optimization-validation/approval.js
+++ b/ci/test-optimization-validation/approval.js
@@ -240,21 +240,25 @@ function getApprovalCommand (id, command) {
  */
 function getGeneratedFileMaterial (manifest, requestedScenario) {
   const files = []
-  for (const framework of manifest.frameworks || []) {
-    const strategy = framework.generatedTestStrategy
-    const selectedPaths = getSelectedGeneratedPaths(strategy, requestedScenario)
-    for (const file of strategy?.files || []) {
-      if (!selectedPaths.has(path.resolve(file.path))) continue
-      const content = `${file.contentLines.join('\n')}\n`
-      files.push(sanitizeForReport({
-        frameworkId: framework.id,
-        path: path.resolve(file.path),
-        sha256: crypto.createHash('sha256').update(content).digest('hex'),
-        content,
-        removeAfterValidation: (strategy.cleanupPaths || []).some(cleanupPath => {
-          return path.resolve(cleanupPath) === path.resolve(file.path)
-        }),
-      }))
+  if (manifest.frameworks) {
+    for (const framework of manifest.frameworks) {
+      const strategy = framework.generatedTestStrategy
+      const selectedPaths = getSelectedGeneratedPaths(strategy, requestedScenario)
+      if (strategy?.files) {
+        for (const file of strategy.files) {
+          if (!selectedPaths.has(path.resolve(file.path))) continue
+          const content = `${file.contentLines.join('\n')}\n`
+          files.push(sanitizeForReport({
+            frameworkId: framework.id,
+            path: path.resolve(file.path),
+            sha256: crypto.createHash('sha256').update(content).digest('hex'),
+            content,
+            removeAfterValidation: (strategy.cleanupPaths || []).some(cleanupPath => {
+              return path.resolve(cleanupPath) === path.resolve(file.path)
+            }),
+          }))
+        }
+      }
     }
   }
   return files
@@ -278,9 +282,11 @@ function getSelectedGeneratedPaths (strategy, requestedScenario) {
     return path.resolve(scenario.testIdentities[0].file)
   }))
   const selectedPaths = new Set()
-  for (const file of strategy.files || []) {
-    const filename = path.resolve(file.path)
-    if (!requestedScenario || !scenarioPaths.has(filename)) selectedPaths.add(filename)
+  if (strategy.files) {
+    for (const file of strategy.files) {
+      const filename = path.resolve(file.path)
+      if (!requestedScenario || !scenarioPaths.has(filename)) selectedPaths.add(filename)
+    }
   }
   if (generatedId) {
     const scenario = strategy.scenarios?.find(candidate => candidate.id === generatedId)
diff --git a/ci/test-optimization-validation/ci-discovery.js b/ci/test-optimization-validation/ci-discovery.js
index 483fc46bad8..28b86fe68fe 100644
--- a/ci/test-optimization-validation/ci-discovery.js
+++ b/ci/test-optimization-validation/ci-discovery.js
@@ -61,18 +61,22 @@ function buildCiDiscovery ({ manifest, diagnosis }) {
 function getManifestWorkflowLocations (manifest) {
   const root = manifest.repository?.root
   const locations = []
-  for (const framework of manifest.frameworks || []) {
-    const configFile = framework.ciWiring?.configFile
-    if (typeof configFile !== 'string') continue
-    if (!root || !path.isAbsolute(configFile)) {
-      locations.push(configFile)
-      continue
+  if (manifest.frameworks) {
+    for (const framework of manifest.frameworks) {
+      const configFile = framework.ciWiring?.configFile
+      if (typeof configFile !== 'string') continue
+      if (!root || !path.isAbsolute(configFile)) {
+        locations.push(configFile)
+        continue
+      }
+
+      const relative = path.relative(root, configFile)
+      const isRelativePath = relative && relative !== '..' && !relative.startsWith(`..${path.sep}`) &&
+        !path.isAbsolute(relative)
+      locations.push(isRelativePath
+        ? relative.split(path.sep).join('/')
+        : configFile)
     }
-
-    const relative = path.relative(root, configFile)
-    locations.push(relative && relative !== '..' && !relative.startsWith(`..${path.sep}`) && !path.isAbsolute(relative)
-      ? relative.split(path.sep).join('/')
-      : configFile)
   }
   return uniqueStrings(locations)
 }
@@ -106,12 +110,14 @@ function getCiDiscoveryContradictions ({ manifest, declaredFound, staticFound })
     )
   }
 
-  for (const framework of manifest.frameworks || []) {
-    if (!frameworkClaimsNoCi(framework)) continue
-    contradictions.push(
-      `framework ${framework.id || '<unknown>'} records no CI workflow, but static diagnosis found ` +
-        formatList(staticFound)
-    )
+  if (manifest.frameworks) {
+    for (const framework of manifest.frameworks) {
+      if (!frameworkClaimsNoCi(framework)) continue
+      contradictions.push(
+        `framework ${framework.id || '<unknown>'} records no CI workflow, but static diagnosis found ` +
+          formatList(staticFound)
+      )
+    }
   }
 
   return contradictions
diff --git a/ci/test-optimization-validation/command-runner.js b/ci/test-optimization-validation/command-runner.js
index c20b790af7d..ecf4e1b8c90 100644
--- a/ci/test-optimization-validation/command-runner.js
+++ b/ci/test-optimization-validation/command-runner.js
@@ -555,11 +555,13 @@ function buildOfflineValidationEnv ({ fixture, outputRoot }) {
  */
 function assertNoInlineValidationEnvOverrides (command, env) {
   if (!env[VALIDATION_MODE_ENV]) return
-  for (const name of Object.keys(command.env || {})) {
-    const normalized = process.platform === 'win32' ? name.toUpperCase() : name
-    if (VALIDATION_RESERVED_ENV_NAMES.some(reserved => environmentNamesEqual(reserved, name)) ||
-      isDatadogEnvironmentName(name) || normalized.startsWith('OTEL_')) {
-      throw new Error(`Direct-runner adapter must not override validator-controlled environment variable ${name}.`)
+  if (command.env) {
+    for (const name of Object.keys(command.env)) {
+      const normalized = process.platform === 'win32' ? name.toUpperCase() : name
+      if (VALIDATION_RESERVED_ENV_NAMES.some(reserved => environmentNamesEqual(reserved, name)) ||
+        isDatadogEnvironmentName(name) || normalized.startsWith('OTEL_')) {
+        throw new Error(`Direct-runner adapter must not override validator-controlled environment variable ${name}.`)
+      }
     }
   }
 }
diff --git a/ci/test-optimization-validation/environment.js b/ci/test-optimization-validation/environment.js
index 7dbced529b3..bbbd8e5bb26 100644
--- a/ci/test-optimization-validation/environment.js
+++ b/ci/test-optimization-validation/environment.js
@@ -63,8 +63,10 @@ function setEnvironmentValue (environment, name, value, platform = process.platf
  * @returns {void}
  */
 function mergeEnvironment (target, source, platform = process.platform) {
-  for (const [name, value] of Object.entries(source || {})) {
-    setEnvironmentValue(target, name, value, platform)
+  if (source) {
+    for (const [name, value] of Object.entries(source)) {
+      setEnvironmentValue(target, name, value, platform)
+    }
   }
 }
 
diff --git a/ci/test-optimization-validation/executable.js b/ci/test-optimization-validation/executable.js
index 0af544e623d..05201fe35ed 100644
--- a/ci/test-optimization-validation/executable.js
+++ b/ci/test-optimization-validation/executable.js
@@ -40,19 +40,21 @@ function getResolvedExecutable (command) {
  */
 function bindManifestExecutables (manifest) {
   const identities = []
-  for (const framework of manifest.frameworks || []) {
-    if (framework.status !== 'runnable') continue
-    const command = getManifestCommands({ frameworks: [framework] })[0]?.[1]
-    try {
-      const identity = getCommandExecutableIdentity(command, manifest.repository.root)
-      bindApprovedExecutable(framework.validation, identity)
-      identities.push({ id: `framework:${framework.id}`, ...identity })
-    } catch (error) {
-      identities.push({
-        id: `framework:${framework.id}`,
-        unavailable: true,
-        reason: error?.message || String(error),
-      })
+  if (manifest.frameworks) {
+    for (const framework of manifest.frameworks) {
+      if (framework.status !== 'runnable') continue
+      const command = getManifestCommands({ frameworks: [framework] })[0]?.[1]
+      try {
+        const identity = getCommandExecutableIdentity(command, manifest.repository.root)
+        bindApprovedExecutable(framework.validation, identity)
+        identities.push({ id: `framework:${framework.id}`, ...identity })
+      } catch (error) {
+        identities.push({
+          id: `framework:${framework.id}`,
+          unavailable: true,
+          reason: error?.message || String(error),
+        })
+      }
     }
   }
   return identities
diff --git a/ci/test-optimization-validation/generated-files.js b/ci/test-optimization-validation/generated-files.js
index 32ad84281ba..fccd9588ca7 100644
--- a/ci/test-optimization-validation/generated-files.js
+++ b/ci/test-optimization-validation/generated-files.js
@@ -91,14 +91,16 @@ function cleanupGeneratedFiles (manifest, { keep = false } = {}) {
     filesRemoved: 0,
     filesRetained: 0,
   }
-  for (const framework of manifest.frameworks || []) {
-    const strategy = framework.generatedTestStrategy
-    addCleanupOutcome(
-      outcome,
-      cleanupPaths(getSafeCleanupPaths(framework, strategy, { includeGeneratedFiles: true })),
-      'files'
-    )
-    addCleanupOutcome(outcome, cleanupCreatedDirectories(framework.project.root), 'directories')
+  if (manifest.frameworks) {
+    for (const framework of manifest.frameworks) {
+      const strategy = framework.generatedTestStrategy
+      addCleanupOutcome(
+        outcome,
+        cleanupPaths(getSafeCleanupPaths(framework, strategy, { includeGeneratedFiles: true })),
+        'files'
+      )
+      addCleanupOutcome(outcome, cleanupCreatedDirectories(framework.project.root), 'directories')
+    }
   }
   outcome.status = outcome.filesRetained > 0 || outcome.directoriesRetained > 0
     ? 'incomplete'
@@ -168,13 +170,15 @@ function initializeRuntimeCleanupFiles (framework, strategy) {
   if (initializedCleanupStrategies.has(strategy)) return
 
   const generatedFiles = new Set((strategy.files || []).map(file => validateGeneratedFilePath(framework, file.path)))
-  for (const cleanupPath of strategy.cleanupPaths || []) {
-    const filename = validateCleanupPath(framework, cleanupPath)
-    if (generatedFiles.has(filename) || isDirectory(filename) || !isNamespacedRuntimeFile(filename)) continue
-    if (fs.existsSync(filename)) {
-      throw new Error(`Refusing to delete pre-existing generated validation runtime file: ${filename}`)
+  if (strategy.cleanupPaths) {
+    for (const cleanupPath of strategy.cleanupPaths) {
+      const filename = validateCleanupPath(framework, cleanupPath)
+      if (generatedFiles.has(filename) || isDirectory(filename) || !isNamespacedRuntimeFile(filename)) continue
+      if (fs.existsSync(filename)) {
+        throw new Error(`Refusing to delete pre-existing generated validation runtime file: ${filename}`)
+      }
+      authorizedRuntimeCleanupFiles.set(filename, authorizePathForCleanup(framework.project.root, filename))
     }
-    authorizedRuntimeCleanupFiles.set(filename, authorizePathForCleanup(framework.project.root, filename))
   }
   initializedCleanupStrategies.add(strategy)
 }
@@ -183,20 +187,24 @@ function getSafeCleanupPaths (framework, strategy, { includeGeneratedFiles }) {
   if (!strategy) return []
 
   const generatedFiles = new Set()
-  for (const file of strategy.files || []) {
-    generatedFiles.add(validateGeneratedFilePath(framework, file.path))
+  if (strategy.files) {
+    for (const file of strategy.files) {
+      generatedFiles.add(validateGeneratedFilePath(framework, file.path))
+    }
   }
 
   const cleanupPaths = []
-  for (const cleanupPath of strategy.cleanupPaths || []) {
-    const filename = validateCleanupPath(framework, cleanupPath)
-    if (generatedFiles.has(filename)) {
-      if (includeGeneratedFiles && writtenGeneratedFiles.has(filename)) cleanupPaths.push(filename)
-      continue
-    }
+  if (strategy.cleanupPaths) {
+    for (const cleanupPath of strategy.cleanupPaths) {
+      const filename = validateCleanupPath(framework, cleanupPath)
+      if (generatedFiles.has(filename)) {
+        if (includeGeneratedFiles && writtenGeneratedFiles.has(filename)) cleanupPaths.push(filename)
+        continue
+      }
 
-    if (authorizedRuntimeCleanupFiles.has(filename)) {
-      cleanupPaths.push(filename)
+      if (authorizedRuntimeCleanupFiles.has(filename)) {
+        cleanupPaths.push(filename)
+      }
     }
   }
 
@@ -264,10 +272,12 @@ function authorizePathForCleanup (root, filename) {
 }
 
 function pinRuntimeCleanupParents (strategy) {
-  for (const cleanupPath of strategy.cleanupPaths || []) {
-    const authorization = authorizedRuntimeCleanupFiles.get(path.resolve(cleanupPath))
-    if (authorization && authorization.physicalParent === undefined) {
-      pinCleanupParent(authorization, cleanupPath)
+  if (strategy.cleanupPaths) {
+    for (const cleanupPath of strategy.cleanupPaths) {
+      const authorization = authorizedRuntimeCleanupFiles.get(path.resolve(cleanupPath))
+      if (authorization && authorization.physicalParent === undefined) {
+        pinCleanupParent(authorization, cleanupPath)
+      }
     }
   }
 }
diff --git a/ci/test-optimization-validation/generated-verifier.js b/ci/test-optimization-validation/generated-verifier.js
index b20e961bacb..05b47d1d5f9 100644
--- a/ci/test-optimization-validation/generated-verifier.js
+++ b/ci/test-optimization-validation/generated-verifier.js
@@ -209,14 +209,16 @@ function getVerificationFailure (framework, evidence, artifacts, scenario, resul
 function getGeneratedRuntimeFileStatus (strategy) {
   const generatedFiles = new Set((strategy.files || []).map(file => path.resolve(file.path)))
   let expectsRuntimeFile = false
-  for (const cleanupPath of strategy.cleanupPaths || []) {
-    const filename = path.resolve(cleanupPath)
-    if (generatedFiles.has(filename)) continue
-    expectsRuntimeFile = true
-    try {
-      const stat = fs.lstatSync(filename)
-      if (!stat.isSymbolicLink() && stat.isFile()) return true
-    } catch {}
+  if (strategy.cleanupPaths) {
+    for (const cleanupPath of strategy.cleanupPaths) {
+      const filename = path.resolve(cleanupPath)
+      if (generatedFiles.has(filename)) continue
+      expectsRuntimeFile = true
+      try {
+        const stat = fs.lstatSync(filename)
+        if (!stat.isSymbolicLink() && stat.isFile()) return true
+      } catch {}
+    }
   }
   return expectsRuntimeFile ? false : undefined
 }
diff --git a/ci/test-optimization-validation/manifest-scaffold.js b/ci/test-optimization-validation/manifest-scaffold.js
index 40fe6f60932..aa0f7a41bc4 100644
--- a/ci/test-optimization-validation/manifest-scaffold.js
+++ b/ci/test-optimization-validation/manifest-scaffold.js
@@ -457,15 +457,17 @@ function buildFramework (repositoryRoot, detection, ciDiscovery) {
 
 function getImplicitConfigFiles (framework, projectRoot, repositoryRoot) {
   const files = []
-  for (const basename of IMPLICIT_CONFIG_FILENAMES[framework] || []) {
-    const filename = path.join(projectRoot, basename)
-    try {
-      const stat = fs.lstatSync(filename)
-      const physical = fs.realpathSync(filename)
-      if (stat.isFile() && !stat.isSymbolicLink() &&
-        fs.statSync(physical).isFile() &&
-        isPathInside(fs.realpathSync(repositoryRoot), physical)) files.push(physical)
-    } catch {}
+  if (IMPLICIT_CONFIG_FILENAMES[framework]) {
+    for (const basename of IMPLICIT_CONFIG_FILENAMES[framework]) {
+      const filename = path.join(projectRoot, basename)
+      try {
+        const stat = fs.lstatSync(filename)
+        const physical = fs.realpathSync(filename)
+        if (stat.isFile() && !stat.isSymbolicLink() &&
+          fs.statSync(physical).isFile() &&
+          isPathInside(fs.realpathSync(repositoryRoot), physical)) files.push(physical)
+      } catch {}
+    }
   }
   return files
 }
@@ -1135,9 +1137,11 @@ function getFrameworkPackageJson (repositoryRoot, detection) {
   if (preciseLocation) return findOwningPackageJson(repositoryRoot, preciseLocation)
 
   const owners = new Map()
-  for (const location of detection.locations || []) {
-    const owner = findOwningPackageJson(repositoryRoot, location)
-    if (owner) owners.set(owner.path, owner)
+  if (detection.locations) {
+    for (const location of detection.locations) {
+      const owner = findOwningPackageJson(repositoryRoot, location)
+      if (owner) owners.set(owner.path, owner)
+    }
   }
   if (owners.size === 1) return [...owners.values()][0]
 }
diff --git a/ci/test-optimization-validation/manifest-schema.js b/ci/test-optimization-validation/manifest-schema.js
index 0bba03efd1f..622c7fce084 100644
--- a/ci/test-optimization-validation/manifest-schema.js
+++ b/ci/test-optimization-validation/manifest-schema.js
@@ -239,21 +239,23 @@ function validateRunnableFramework (repositoryRoot, framework, prefix, generated
     if (runnerInputError) errors.push(`${prefix}.validation runner configuration ${runnerInputError}.`)
   }
   validateStringArray(validation.requiredEnvVars, `${prefix}.validation.requiredEnvVars`, errors)
-  for (const name of validation.requiredEnvVars || []) {
-    if (!ENV_NAME_PATTERN.test(name)) {
-      errors.push(`${prefix}.validation.requiredEnvVars contains an invalid environment name.`)
-    }
-    if (/^(?:DD_|DATADOG_|OTEL_|NODE_OPTIONS$|TS_NODE_PROJECT$)/i.test(name)) {
-      errors.push(
-        `${prefix}.validation.requiredEnvVars must not inherit Datadog, OpenTelemetry, NODE_OPTIONS, or ` +
-          'TS_NODE_PROJECT.'
-      )
-    }
-    if (SECRET_ENV_PATTERN.test(name)) {
-      errors.push(`${prefix}.validation.requiredEnvVars must not inherit secret-like environment variables.`)
-    }
-    if (EXECUTION_ENV_PATTERN.test(name)) {
-      errors.push(`${prefix}.validation.requiredEnvVars must not inherit executable-loading environment variables.`)
+  if (validation.requiredEnvVars) {
+    for (const name of validation.requiredEnvVars) {
+      if (!ENV_NAME_PATTERN.test(name)) {
+        errors.push(`${prefix}.validation.requiredEnvVars contains an invalid environment name.`)
+      }
+      if (/^(?:DD_|DATADOG_|OTEL_|NODE_OPTIONS$|TS_NODE_PROJECT$)/i.test(name)) {
+        errors.push(
+          `${prefix}.validation.requiredEnvVars must not inherit Datadog, OpenTelemetry, NODE_OPTIONS, or ` +
+            'TS_NODE_PROJECT.'
+        )
+      }
+      if (SECRET_ENV_PATTERN.test(name)) {
+        errors.push(`${prefix}.validation.requiredEnvVars must not inherit secret-like environment variables.`)
+      }
+      if (EXECUTION_ENV_PATTERN.test(name)) {
+        errors.push(`${prefix}.validation.requiredEnvVars must not inherit executable-loading environment variables.`)
+      }
     }
   }
   if (!Number.isInteger(validation.timeoutMs) || validation.timeoutMs < 1 || validation.timeoutMs > MAX_TIMEOUT_MS) {
diff --git a/ci/test-optimization-validation/plan-writer.js b/ci/test-optimization-validation/plan-writer.js
index 11f4d4b6191..d4d2c00d4f4 100644
--- a/ci/test-optimization-validation/plan-writer.js
+++ b/ci/test-optimization-validation/plan-writer.js
@@ -176,7 +176,9 @@ function formatApprovalPlan ({
           ? [`Blocker: ${plain(framework.blockerCategory.replaceAll('_', ' '))}.`]
           : [])
       )
-      for (const note of framework.notes || []) lines.push(`- ${plain(note)}`)
+      if (framework.notes) {
+        for (const note of framework.notes) lines.push(`- ${plain(note)}`)
+      }
       lines.push('')
       continue
     }
diff --git a/ci/test-optimization-validation/runner-command.js b/ci/test-optimization-validation/runner-command.js
index a6bd6841bac..27fc1b85efa 100644
--- a/ci/test-optimization-validation/runner-command.js
+++ b/ci/test-optimization-validation/runner-command.js
@@ -50,12 +50,18 @@ function getFrameworkCommands (framework, requestedScenario = null) {
   if (requestedScenario === 'ci-wiring') return []
 
   const commands = [['basic-reporting', getBasicCommand(framework)]]
-  for (const [index, fallback] of (framework.validation.fallbackTests || []).entries()) {
-    commands.push([`basic-reporting:fallback-${index + 1}`, getBasicCommand(framework, fallback.testFile)])
+  const fallbackTests = framework.validation.fallbackTests
+  if (fallbackTests) {
+    for (const [index, fallback] of fallbackTests.entries()) {
+      commands.push([`basic-reporting:fallback-${index + 1}`, getBasicCommand(framework, fallback.testFile)])
+    }
   }
-  for (const scenario of framework.generatedTestStrategy?.scenarios || []) {
-    if (!shouldIncludeGeneratedScenario(scenario.id, requestedScenario)) continue
-    commands.push([`generated:${scenario.id}`, getGeneratedCommand(framework, scenario)])
+  const scenarios = framework.generatedTestStrategy?.scenarios
+  if (scenarios) {
+    for (const scenario of scenarios) {
+      if (!shouldIncludeGeneratedScenario(scenario.id, requestedScenario)) continue
+      commands.push([`generated:${scenario.id}`, getGeneratedCommand(framework, scenario)])
+    }
   }
   return commands
 }
@@ -69,9 +75,11 @@ function getFrameworkCommands (framework, requestedScenario = null) {
  */
 function getManifestCommands (manifest, requestedScenario = null) {
   const commands = []
-  for (const framework of manifest.frameworks || []) {
-    for (const [label, command] of getFrameworkCommands(framework, requestedScenario)) {
-      commands.push([`${framework.id}:${label}`, command])
+  if (manifest.frameworks) {
+    for (const framework of manifest.frameworks) {
+      for (const [label, command] of getFrameworkCommands(framework, requestedScenario)) {
+        commands.push([`${framework.id}:${label}`, command])
+      }
     }
   }
   return commands
@@ -87,15 +95,23 @@ function getManifestCommands (manifest, requestedScenario = null) {
  */
 function getManifestInputFiles (manifest, { includeLocal = true } = {}) {
   const files = new Set()
-  for (const framework of manifest.frameworks || []) {
-    addExistingFile(files, framework.ciWiring?.configFile)
-    addExistingFile(files, framework.project?.packageJson)
-    if (!includeLocal) continue
-    if (framework.status !== 'runnable') continue
-    addExistingFile(files, framework.validation?.runner)
-    addExistingFile(files, framework.validation?.testFile)
-    for (const fallback of framework.validation?.fallbackTests || []) addExistingFile(files, fallback.testFile)
-    for (const filename of framework.project?.configFiles || []) addExistingFile(files, filename)
+  if (manifest.frameworks) {
+    for (const framework of manifest.frameworks) {
+      addExistingFile(files, framework.ciWiring?.configFile)
+      addExistingFile(files, framework.project?.packageJson)
+      if (!includeLocal) continue
+      if (framework.status !== 'runnable') continue
+      addExistingFile(files, framework.validation?.runner)
+      addExistingFile(files, framework.validation?.testFile)
+      const fallbackTests = framework.validation?.fallbackTests
+      if (fallbackTests) {
+        for (const fallback of fallbackTests) addExistingFile(files, fallback.testFile)
+      }
+      const configFiles = framework.project?.configFiles
+      if (configFiles) {
+        for (const filename of configFiles) addExistingFile(files, filename)
+      }
+    }
   }
   return [...files].sort()
 }
diff --git a/ci/test-optimization-validation/runner-contract.js b/ci/test-optimization-validation/runner-contract.js
index f2d5e018edc..895ed52d8d5 100644
--- a/ci/test-optimization-validation/runner-contract.js
+++ b/ci/test-optimization-validation/runner-contract.js
@@ -432,10 +432,12 @@ function getRunnerInputError (args, environment, projectRoot, repositoryRoot, co
   if (inputs.error) return inputs.error
 
   const approved = new Set()
-  for (const filename of configFiles || []) {
-    try {
-      approved.add(fs.realpathSync(filename))
-    } catch {}
+  if (configFiles) {
+    for (const filename of configFiles) {
+      try {
+        approved.add(fs.realpathSync(filename))
+      } catch {}
+    }
   }
   const unbound = inputs.files.find(filename => !approved.has(filename))
   if (unbound) return `references an input that is not approval-bound: ${unbound}`
diff --git a/ci/test-optimization-validation/static-diagnosis.js b/ci/test-optimization-validation/static-diagnosis.js
index 636fc035940..c080d112655 100644
--- a/ci/test-optimization-validation/static-diagnosis.js
+++ b/ci/test-optimization-validation/static-diagnosis.js
@@ -121,8 +121,11 @@ function getExactFrameworkLocations (diagnosis, framework) {
   const locations = new Set()
   addRelativeFrameworkLocation(locations, diagnosis, framework.project?.packageJson)
 
-  for (const configFile of framework.project?.configFiles || []) {
-    addRelativeFrameworkLocation(locations, diagnosis, configFile)
+  const configFiles = framework.project?.configFiles
+  if (configFiles) {
+    for (const configFile of configFiles) {
+      addRelativeFrameworkLocation(locations, diagnosis, configFile)
+    }
   }
 
   return locations
diff --git a/ci/vitest-no-worker-init-setup.mjs b/ci/vitest-no-worker-init-setup.mjs
index 2372e1baff9..feb84f3e4c4 100644
--- a/ci/vitest-no-worker-init-setup.mjs
+++ b/ci/vitest-no-worker-init-setup.mjs
@@ -109,26 +109,29 @@ if (isNoWorkerInitActive) {
 }
 
 function applyExecutionChanges (suite) {
-  for (const task of suite?.tasks || []) {
-    if (task.type === 'suite') {
-      applyExecutionChanges(task)
-      continue
-    }
+  const tasks = suite?.tasks
+  if (tasks) {
+    for (const task of tasks) {
+      if (task.type === 'suite') {
+        applyExecutionChanges(task)
+        continue
+      }
 
-    const testSuite = getTestSuite(task)
-    const testName = getTestName(task)
-    if (attemptToFixTests[testSuite]?.[testName]) {
-      task.retry = 0
-      task.repeats = attemptToFixRetries
-      task.meta.__ddTestOptAtfRetries = attemptToFixRetries
-    } else if (disabledTests[testSuite]?.[testName]) {
-      task.mode = 'skip'
-    } else if (isEarlyFlakeDetectionTest(testSuite, testName)) {
-      task.retry = 0
-      task.repeats = earlyFlakeDetectionRetries
-      task.meta.__ddTestOptEfdRetries = earlyFlakeDetectionRetries
+      const testSuite = getTestSuite(task)
+      const testName = getTestName(task)
+      if (attemptToFixTests[testSuite]?.[testName]) {
+        task.retry = 0
+        task.repeats = attemptToFixRetries
+        task.meta.__ddTestOptAtfRetries = attemptToFixRetries
+      } else if (disabledTests[testSuite]?.[testName]) {
+        task.mode = 'skip'
+      } else if (isEarlyFlakeDetectionTest(testSuite, testName)) {
+        task.retry = 0
+        task.repeats = earlyFlakeDetectionRetries
+        task.meta.__ddTestOptEfdRetries = earlyFlakeDetectionRetries
+      }
+      wrapRetryCondition(task)
     }
-    wrapRetryCondition(task)
   }
 }
 
diff --git a/eslint.config.mjs b/eslint.config.mjs
index 2290258b348..40f8cf51b56 100644
--- a/eslint.config.mjs
+++ b/eslint.config.mjs
@@ -645,6 +645,7 @@ export default [
       ...eslintPluginUnicorn.configs.recommended.rules,
 
       // Not in `recommended`: the innerHTML sink class and unread object properties.
+      'unicorn/iteration-fallback-style': 'error',
       'unicorn/no-unsafe-dom-html': 'error',
       'unicorn/no-unused-properties': 'error',
 
@@ -699,6 +700,7 @@ export default [
       'unicorn/prefer-simple-condition-first': 'off', // lots | needs a short-circuit behavior audit
       'unicorn/prefer-then-catch': 'off', // many | broadens rejection boundaries
       'unicorn/require-array-sort-compare': 'off', // many | many intentional lexicographic sorts
+      'unicorn/single-line-block-comment-style': 'off', // lots | preserve compact JSDoc typedefs
 
       // The following rules should not be activated!
       'unicorn/consistent-boolean-name': 'off', // Would rename public API and config booleans
diff --git a/package.json b/package.json
index 5d57dad60f8..0ead1995ffc 100644
--- a/package.json
+++ b/package.json
@@ -219,7 +219,7 @@
     "eslint-plugin-n": "^18.2.1",
     "eslint-plugin-promise": "^7.3.0",
     "eslint-plugin-sonarjs": "^4.2.0",
-    "eslint-plugin-unicorn": "^72.0.0",
+    "eslint-plugin-unicorn": "^73.0.0",
     "express": "^5.1.0",
     "glob": "^10.4.5",
     "globals": "^17.7.0",
diff --git a/packages/datadog-instrumentations/src/helpers/router-helper.js b/packages/datadog-instrumentations/src/helpers/router-helper.js
index cc32812bc3f..05c2a231944 100644
--- a/packages/datadog-instrumentations/src/helpers/router-helper.js
+++ b/packages/datadog-instrumentations/src/helpers/router-helper.js
@@ -68,12 +68,14 @@ function collectRoutesFromRouter (router, prefix) {
       const fullPaths = getRouteFullPaths(route, prefix)
 
       for (const fullPath of fullPaths) {
-        for (const [method, enabled] of Object.entries(route.methods || {})) {
-          if (!enabled) continue
-          routeAddedChannel.publish({
-            method: normalizeMethodName(method),
-            path: fullPath,
-          })
+        if (route.methods) {
+          for (const [method, enabled] of Object.entries(route.methods)) {
+            if (!enabled) continue
+            routeAddedChannel.publish({
+              method: normalizeMethodName(method),
+              path: fullPath,
+            })
+          }
         }
       }
     } else if (layer.handle?.stack?.length) {
diff --git a/packages/datadog-instrumentations/src/jest.js b/packages/datadog-instrumentations/src/jest.js
index e8dd88f7f63..f1ece57984a 100644
--- a/packages/datadog-instrumentations/src/jest.js
+++ b/packages/datadog-instrumentations/src/jest.js
@@ -2254,16 +2254,15 @@ function getWrappedEnvironment (BaseEnvironment, jestVersion) {
         this.#efdRetryGatesByName = undefined
         this.#detachedEfdRetryQueue = undefined
         testSuiteDatadogEnvironments.delete(this.testSuiteAbsolutePath)
-      }
-      if (event.name === 'test_skip' || event.name === 'test_todo') {
+      } else if (event.name === 'test_skip' || event.name === 'test_todo') {
         const testName = getJestTestName(event.test)
         const retryGates = this.#efdRetryGatesByName?.get(testName)
-        if (retryGates && efdRetryMetadataByTest.has(event.test)) {
-          this.#discardedEfdRetryTests ??= new Set()
-          this.#discardedEfdRetryTests.add(event.test)
-          return
-        }
         if (retryGates) {
+          if (efdRetryMetadataByTest.has(event.test)) {
+            this.#discardedEfdRetryTests ??= new Set()
+            this.#discardedEfdRetryTests.add(event.test)
+            return
+          }
           for (const gate of retryGates) {
             gate.resolve(false)
           }
diff --git a/packages/datadog-instrumentations/src/jest/coverage-backfill.js b/packages/datadog-instrumentations/src/jest/coverage-backfill.js
index b1ed08bc63c..4bc9bea5c0e 100644
--- a/packages/datadog-instrumentations/src/jest/coverage-backfill.js
+++ b/packages/datadog-instrumentations/src/jest/coverage-backfill.js
@@ -14,7 +14,7 @@ const TRANSFORM_OPTIONS = {
 
 function getCoverageBackfillFiles (skippableSuitesCoverage, rootDir, getTestSuitePath) {
   const files = []
-  for (const filename of Object.keys(skippableSuitesCoverage || {})) {
+  for (const filename of Object.keys(skippableSuitesCoverage)) {
     const relativeFilename = path.isAbsolute(filename)
       ? getTestSuitePath(filename, rootDir)
       : filename
diff --git a/packages/datadog-instrumentations/src/mocha/worker.js b/packages/datadog-instrumentations/src/mocha/worker.js
index 0d4f6d26cca..93d98ca050b 100644
--- a/packages/datadog-instrumentations/src/mocha/worker.js
+++ b/packages/datadog-instrumentations/src/mocha/worker.js
@@ -239,7 +239,7 @@ function getWebdriverioHookTest (hook) {
  */
 function adjustWebdriverioHookFailures (runner) {
   let suppressedFailures = 0
-  for (const { test } of runnerToFailedHooks.get(runner) || []) {
+  for (const { test } of runnerToFailedHooks.get(runner)) {
     if (isWebdriverioFailureSuppressed(test)) {
       suppressedFailures++
     }
@@ -281,7 +281,7 @@ function getWebdriverioSuiteResults (runner) {
     }
   })
 
-  for (const { file, test } of runnerToFailedHooks.get(runner) || []) {
+  for (const { file, test } of runnerToFailedHooks.get(runner)) {
     const result = resultsByFile.get(file)
     if (result && !isWebdriverioFailureSuppressed(test)) {
       result.status = 'fail'
diff --git a/packages/datadog-instrumentations/src/vitest-worker.js b/packages/datadog-instrumentations/src/vitest-worker.js
index b483f1d989e..bbaa73157c4 100644
--- a/packages/datadog-instrumentations/src/vitest-worker.js
+++ b/packages/datadog-instrumentations/src/vitest-worker.js
@@ -137,8 +137,8 @@ function isFileInRepository (filename, repositoryRoot) {
 }
 
 function isV8ScriptCovered (scriptCoverage) {
-  for (const functionCoverage of scriptCoverage.functions || []) {
-    for (const range of functionCoverage.ranges || []) {
+  for (const functionCoverage of scriptCoverage.functions) {
+    for (const range of functionCoverage.ranges) {
       if (range.count > 0) return true
     }
   }
@@ -147,15 +147,18 @@ function isV8ScriptCovered (scriptCoverage) {
 
 function getCoveredFilesFromV8Result (coverage, repositoryRoot) {
   const coveredFiles = []
-  for (const scriptCoverage of coverage?.result || []) {
-    if (!isV8ScriptCovered(scriptCoverage)) continue
+  const scriptCoverageResults = coverage?.result
+  if (scriptCoverageResults) {
+    for (const scriptCoverage of scriptCoverageResults) {
+      if (!isV8ScriptCovered(scriptCoverage)) continue
 
-    const coverageFilename = getCoverageFilename(scriptCoverage.url)
-    if (!coverageFilename) continue
+      const coverageFilename = getCoverageFilename(scriptCoverage.url)
+      if (!coverageFilename) continue
 
-    const filename = realpath(coverageFilename)
-    if (isFileInRepository(filename, repositoryRoot)) {
-      coveredFiles.push(filename)
+      const filename = realpath(coverageFilename)
+      if (isFileInRepository(filename, repositoryRoot)) {
+        coveredFiles.push(filename)
+      }
     }
   }
   return coveredFiles
diff --git a/packages/datadog-instrumentations/src/webdriverio.js b/packages/datadog-instrumentations/src/webdriverio.js
index 4a6a81a0a00..2b9ed41231e 100644
--- a/packages/datadog-instrumentations/src/webdriverio.js
+++ b/packages/datadog-instrumentations/src/webdriverio.js
@@ -1002,9 +1002,13 @@ launcherStartInstanceCh.subscribe({
 
     const state = getCoordinatorState(localRunner)
     addScheduledFiles(state, context.arguments?.[0] || [])
-    for (const schedule of context.self._schedule || []) {
-      for (const { files } of schedule.specs || []) {
-        addScheduledFiles(state, files)
+    if (context.self._schedule) {
+      for (const schedule of context.self._schedule) {
+        if (schedule.specs) {
+          for (const { files } of schedule.specs) {
+            addScheduledFiles(state, files)
+          }
+        }
       }
     }
   },
diff --git a/packages/datadog-plugin-aws-sdk/src/services/bedrockruntime/utils.js b/packages/datadog-plugin-aws-sdk/src/services/bedrockruntime/utils.js
index 6ee7b84f96d..0cca3fef773 100644
--- a/packages/datadog-plugin-aws-sdk/src/services/bedrockruntime/utils.js
+++ b/packages/datadog-plugin-aws-sdk/src/services/bedrockruntime/utils.js
@@ -487,16 +487,18 @@ function extractMessagesFromConverseContent (role, contentBlocks) {
   const toolCalls = []
   const toolResults = []
 
-  for (const block of contentBlocks || []) {
-    if (block == null || typeof block !== 'object') continue
-    if (typeof block.text === 'string') {
-      content += block.text
-    } else if (block.toolUse) {
-      toolCalls.push(buildToolCall(block.toolUse))
-    } else if (block.toolResult) {
-      toolResults.push(buildToolResult(block.toolResult))
-    } else {
-      content += `[Unsupported content type: ${getContentBlockType(block)}]`
+  if (contentBlocks) {
+    for (const block of contentBlocks) {
+      if (block == null || typeof block !== 'object') continue
+      if (typeof block.text === 'string') {
+        content += block.text
+      } else if (block.toolUse) {
+        toolCalls.push(buildToolCall(block.toolUse))
+      } else if (block.toolResult) {
+        toolResults.push(buildToolResult(block.toolResult))
+      } else {
+        content += `[Unsupported content type: ${getContentBlockType(block)}]`
+      }
     }
   }
 
@@ -572,14 +574,17 @@ function buildUsage (usage = {}) {
  */
 function extractConverseToolDefinitions (params) {
   const toolDefinitions = []
-  for (const tool of params.toolConfig?.tools || []) {
-    const toolSpec = tool?.toolSpec
-    if (!toolSpec?.name) continue
-    toolDefinitions.push({
-      name: toolSpec.name,
-      description: toolSpec.description ?? '',
-      schema: toolSpec.inputSchema ?? {},
-    })
+  const tools = params.toolConfig?.tools
+  if (tools) {
+    for (const tool of tools) {
+      const toolSpec = tool?.toolSpec
+      if (!toolSpec?.name) continue
+      toolDefinitions.push({
+        name: toolSpec.name,
+        description: toolSpec.description ?? '',
+        schema: toolSpec.inputSchema ?? {},
+      })
+    }
   }
   return toolDefinitions
 }
@@ -593,13 +598,17 @@ function extractConverseToolDefinitions (params) {
  */
 function extractRequestParamsConverse (params) {
   const prompt = []
-  for (const block of params.system || []) {
-    if (typeof block?.text === 'string') prompt.push({ content: block.text, role: 'system' })
+  if (params.system) {
+    for (const block of params.system) {
+      if (typeof block?.text === 'string') prompt.push({ content: block.text, role: 'system' })
+    }
   }
-  for (const msg of params.messages || []) {
-    if (msg == null || typeof msg !== 'object') continue
-    const message = extractMessagesFromConverseContent(msg.role || 'user', msg.content)
-    if (message) prompt.push(message)
+  if (params.messages) {
+    for (const msg of params.messages) {
+      if (msg == null || typeof msg !== 'object') continue
+      const message = extractMessagesFromConverseContent(msg.role || 'user', msg.content)
+      if (message) prompt.push(message)
+    }
   }
 
   const { temperature, topP, maxTokens, stopSequences } = params.inferenceConfig || {}
@@ -632,7 +641,7 @@ function extractTextAndResponseReasonConverse (response) {
  * response, spread across start/delta chunks. We reassemble those chunks
  * into a normalized content-block array and reuse the non-stream extractor.
  *
- * @param {Array<object>} chunks - Ordered ConverseStreamOutput events.
+ * @param {Array<object> | undefined} chunks - Ordered ConverseStreamOutput events.
  * @returns {Generation}
  */
 function extractTextAndResponseReasonConverseFromStream (chunks) {
@@ -641,29 +650,31 @@ function extractTextAndResponseReasonConverseFromStream (chunks) {
   let usage = {}
   const blocksByIdx = new Map()
 
-  for (const chunk of chunks || []) {
-    if (chunk.messageStart?.role) {
-      role = chunk.messageStart.role
-    } else if (chunk.messageStop?.stopReason) {
-      stopReason = chunk.messageStop.stopReason
-    } else if (chunk.metadata?.usage) {
-      usage = chunk.metadata.usage
-    } else if (chunk.contentBlockStart?.start?.toolUse) {
-      const { contentBlockIndex, start: { toolUse } } = chunk.contentBlockStart
-      blocksByIdx.set(contentBlockIndex, {
-        toolUse: { toolUseId: toolUse.toolUseId, name: toolUse.name, inputStr: '' },
-      })
-    } else if (chunk.contentBlockDelta) {
-      const { contentBlockIndex, delta } = chunk.contentBlockDelta
-      if (typeof delta?.text === 'string') {
-        const block = blocksByIdx.get(contentBlockIndex) ?? {}
-        block.text = (block.text ?? '') + delta.text
-        blocksByIdx.set(contentBlockIndex, block)
-      } else if (typeof delta?.toolUse?.input === 'string') {
-        const block = blocksByIdx.get(contentBlockIndex) ?? { toolUse: { inputStr: '' } }
-        block.toolUse ??= { inputStr: '' }
-        block.toolUse.inputStr += delta.toolUse.input
-        blocksByIdx.set(contentBlockIndex, block)
+  if (chunks) {
+    for (const chunk of chunks) {
+      if (chunk.messageStart?.role) {
+        role = chunk.messageStart.role
+      } else if (chunk.messageStop?.stopReason) {
+        stopReason = chunk.messageStop.stopReason
+      } else if (chunk.metadata?.usage) {
+        usage = chunk.metadata.usage
+      } else if (chunk.contentBlockStart?.start?.toolUse) {
+        const { contentBlockIndex, start: { toolUse } } = chunk.contentBlockStart
+        blocksByIdx.set(contentBlockIndex, {
+          toolUse: { toolUseId: toolUse.toolUseId, name: toolUse.name, inputStr: '' },
+        })
+      } else if (chunk.contentBlockDelta) {
+        const { contentBlockIndex, delta } = chunk.contentBlockDelta
+        if (typeof delta?.text === 'string') {
+          const block = blocksByIdx.get(contentBlockIndex) ?? {}
+          block.text = (block.text ?? '') + delta.text
+          blocksByIdx.set(contentBlockIndex, block)
+        } else if (typeof delta?.toolUse?.input === 'string') {
+          const block = blocksByIdx.get(contentBlockIndex) ?? { toolUse: { inputStr: '' } }
+          block.toolUse ??= { inputStr: '' }
+          block.toolUse.inputStr += delta.toolUse.input
+          blocksByIdx.set(contentBlockIndex, block)
+        }
       }
     }
   }
diff --git a/packages/datadog-plugin-aws-sdk/test/bedrockruntime.util.spec.js b/packages/datadog-plugin-aws-sdk/test/bedrockruntime.util.spec.js
index df4cc6f905c..762481fef05 100644
--- a/packages/datadog-plugin-aws-sdk/test/bedrockruntime.util.spec.js
+++ b/packages/datadog-plugin-aws-sdk/test/bedrockruntime.util.spec.js
@@ -9,6 +9,36 @@ const {
 } = require('../src/services/bedrockruntime/utils')
 
 describe('bedrockruntime converse stream extractor', () => {
+  it('returns an empty message when the stream fails before yielding a chunk', () => {
+    const generation = extractTextAndResponseReasonConverseFromStream()
+
+    assert.deepStrictEqual(generation.messages, [{ role: 'assistant', content: '' }])
+  })
+
+  it('aggregates streamed text, tool input, metadata, and the stop reason', () => {
+    const generation = extractTextAndResponseReasonConverseFromStream([
+      { messageStart: { role: 'assistant' } },
+      { contentBlockDelta: { contentBlockIndex: 0, delta: { text: 'hel' } } },
+      { contentBlockDelta: { contentBlockIndex: 0, delta: { text: 'lo' } } },
+      { contentBlockDelta: { contentBlockIndex: 1, delta: { toolUse: { input: '{"city":"Berlin"}' } } } },
+      { metadata: { usage: { inputTokens: 2, outputTokens: 3 } } },
+      { messageStop: { stopReason: 'tool_use' } },
+    ])
+
+    assert.deepStrictEqual(generation.messages, [{
+      role: 'assistant',
+      content: 'hello',
+      toolCalls: [{ name: '', arguments: { city: 'Berlin' }, toolId: '', type: 'toolUse' }],
+    }])
+    assert.deepStrictEqual(generation.usage, {
+      inputTokens: 2,
+      outputTokens: 3,
+      cacheReadTokens: undefined,
+      cacheWriteTokens: undefined,
+    })
+    assert.strictEqual(generation.finishReason, 'tool_use')
+  })
+
   it('emits empty tool-call arguments when the streamed tool-use input is malformed JSON', () => {
     const generation = extractTextAndResponseReasonConverseFromStream([
       { messageStart: { role: 'assistant' } },
diff --git a/packages/datadog-plugin-electron/src/net.js b/packages/datadog-plugin-electron/src/net.js
index 1f8675f1482..07bbaf96345 100644
--- a/packages/datadog-plugin-electron/src/net.js
+++ b/packages/datadog-plugin-electron/src/net.js
@@ -64,12 +64,18 @@ class ElectronRequestPlugin extends HttpClientPlugin {
     const responseHead = ctx.res?._responseHead
     const { statusCode } = responseHead || {}
 
-    for (const header in ctx.req._urlLoaderOptions?.headers || {}) {
-      reqHeaders[header.name] = header.value
+    const requestHeaders = ctx.req._urlLoaderOptions?.headers
+    if (requestHeaders) {
+      for (const header in requestHeaders) {
+        reqHeaders[header.name] = header.value
+      }
     }
 
-    for (const header in responseHead?.rawHeaders || {}) {
-      resHeaders[header.name] = header.value
+    const responseHeaders = responseHead?.rawHeaders
+    if (responseHeaders) {
+      for (const header in responseHeaders) {
+        resHeaders[header.name] = header.value
+      }
     }
 
     ctx.req = { headers: reqHeaders }
diff --git a/packages/datadog-plugin-mocha/src/index.js b/packages/datadog-plugin-mocha/src/index.js
index cac667f58bf..4849d048a03 100644
--- a/packages/datadog-plugin-mocha/src/index.js
+++ b/packages/datadog-plugin-mocha/src/index.js
@@ -767,7 +767,7 @@ class MochaPlugin extends CiPlugin {
     const state = this._webdriverioJasmineState
     const results = []
     const reportedFiles = new Set()
-    for (const [file, status] of state?.suiteStatuses || []) {
+    for (const [file, status] of state.suiteStatuses) {
       const error = state.suiteErrors.get(file)
       const result = { file, status }
       if (error) {
@@ -779,7 +779,7 @@ class MochaPlugin extends CiPlugin {
       results.push(result)
       reportedFiles.add(file)
     }
-    for (const spec of state?.specs || []) {
+    for (const spec of state.specs) {
       const file = normalizeJasmineFile(spec)
       if (!reportedFiles.has(file)) {
         results.push({ file, status: 'skip' })
diff --git a/packages/datadog-plugin-vitest/src/index.js b/packages/datadog-plugin-vitest/src/index.js
index 6c4dce36773..b9a8c0df3fa 100644
--- a/packages/datadog-plugin-vitest/src/index.js
+++ b/packages/datadog-plugin-vitest/src/index.js
@@ -593,7 +593,7 @@ class VitestPlugin extends CiPlugin {
       isVitestNoWorkerInitActive,
       onDone,
     }) => {
-      for (const [tag, value] of Object.entries(requestErrorTags || {})) {
+      for (const [tag, value] of Object.entries(requestErrorTags)) {
         this.testSessionSpan.setTag(tag, value)
         this.testModuleSpan.setTag(tag, value)
       }
diff --git a/packages/dd-trace/src/ci-visibility/intelligent-test-runner/get-skippable-suites.js b/packages/dd-trace/src/ci-visibility/intelligent-test-runner/get-skippable-suites.js
index 1700b4550cb..4acd084f19e 100644
--- a/packages/dd-trace/src/ci-visibility/intelligent-test-runner/get-skippable-suites.js
+++ b/packages/dd-trace/src/ci-visibility/intelligent-test-runner/get-skippable-suites.js
@@ -34,8 +34,11 @@ function parseSkippableSuitesResponse (
     validateSkippableTestsResponse(parsedResponse, { validationMode })
   }
   const coverage = {}
-  for (const [filename, bitmap] of Object.entries(parsedResponse.meta?.coverage || {})) {
-    coverage[filename.replaceAll('\\', '/')] = bitmap
+  const coverageByFilename = parsedResponse.meta?.coverage
+  if (coverageByFilename) {
+    for (const [filename, bitmap] of Object.entries(coverageByFilename)) {
+      coverage[filename.replaceAll('\\', '/')] = bitmap
+    }
   }
 
   const skippableItems = parsedResponse
diff --git a/packages/dd-trace/src/config/index.js b/packages/dd-trace/src/config/index.js
index 4ee295e072c..99864e47874 100644
--- a/packages/dd-trace/src/config/index.js
+++ b/packages/dd-trace/src/config/index.js
@@ -194,8 +194,11 @@ class Config extends ConfigBase {
     this.debug = log.configure(options)
 
     // Process stable config warnings, if any
-    for (const warning of this.stableConfig?.warnings ?? []) {
-      log.warn(warning)
+    const stableConfigWarnings = this.stableConfig?.warnings
+    if (stableConfigWarnings) {
+      for (const warning of stableConfigWarnings) {
+        log.warn(warning)
+      }
     }
 
     this.#applyDefaults()
diff --git a/packages/dd-trace/src/config/remote_config.js b/packages/dd-trace/src/config/remote_config.js
index a95ca899a79..644e05d54b0 100644
--- a/packages/dd-trace/src/config/remote_config.js
+++ b/packages/dd-trace/src/config/remote_config.js
@@ -236,7 +236,7 @@ const optionLookupTable = {
 
 const transformers = {
   tracing_sampling_rules (samplingRules) {
-    for (const rule of (samplingRules || [])) {
+    for (const rule of samplingRules) {
       if (rule.tags) {
         const reformattedTags = {}
         for (const tag of rule.tags) {
diff --git a/packages/dd-trace/src/llmobs/experiments/index.js b/packages/dd-trace/src/llmobs/experiments/index.js
index 9eb5ee282a4..2ae22d4181c 100644
--- a/packages/dd-trace/src/llmobs/experiments/index.js
+++ b/packages/dd-trace/src/llmobs/experiments/index.js
@@ -47,15 +47,17 @@ class Experiments {
       : (descriptionOrOptions ?? {})
     const dataset = new Dataset(this.#client, name, options.description ?? '')
     const recordIds = new Set()
-    for (const record of options.records ?? []) {
-      if (record.id !== undefined && (typeof record.id !== 'string' || record.id.length === 0)) {
-        throw new Error('record id must be a non-empty string')
-      }
-      if (record.id !== undefined) {
-        if (recordIds.has(record.id)) throw new Error(`Duplicate record id '${record.id}'`)
-        recordIds.add(record.id)
+    if ((options.records) != null) {
+      for (const record of options.records) {
+        if (record.id !== undefined && (typeof record.id !== 'string' || record.id.length === 0)) {
+          throw new Error('record id must be a non-empty string')
+        }
+        if (record.id !== undefined) {
+          if (recordIds.has(record.id)) throw new Error(`Duplicate record id '${record.id}'`)
+          recordIds.add(record.id)
+        }
+        dataset.addRecord(new DatasetRecord(record.inputData, record.expectedOutput, record.metadata, record.id))
       }
-      dataset.addRecord(new DatasetRecord(record.inputData, record.expectedOutput, record.metadata, record.id))
     }
     return dataset
   }
@@ -82,13 +84,16 @@ class Experiments {
             'GET',
             `${API_BASE_PATH}/${projectId}/datasets?filter[name]=${encodeURIComponent(name)}`
           )
-          for (const item of listed?.data ?? []) {
-            if (item?.attributes?.name === name) {
-              datasetId = String(item?.id ?? '')
-              description = String(item?.attributes?.description ?? '')
-              latestVersion = item?.attributes?.current_version ?? null
-              datasetVersion = version ?? latestVersion
-              break
+          const datasets = listed?.data
+          if (datasets) {
+            for (const item of datasets) {
+              if (item?.attributes?.name === name) {
+                datasetId = String(item?.id ?? '')
+                description = String(item?.attributes?.description ?? '')
+                latestVersion = item?.attributes?.current_version ?? null
+                datasetVersion = version ?? latestVersion
+                break
+              }
             }
           }
           if (datasetId === null) return false
@@ -107,16 +112,19 @@ class Experiments {
             'GET',
             `${API_BASE_PATH}/${projectId}/datasets/${datasetId}/records?${query.toString()}`
           )
-          for (const item of resp?.data ?? []) {
-            const attrs = item?.attributes ?? item
-            const recordId = String(item?.id ?? attrs?.id ?? '')
-            recs.push(new DatasetRecord(
-              attrs?.input ?? null,
-              attrs?.expected_output ?? null,
-              attrs?.metadata ?? {},
-              recordId === '' ? null : recordId
-            ))
-            ids.push(recordId)
+          const recordData = resp?.data
+          if (recordData) {
+            for (const item of recordData) {
+              const attrs = item?.attributes ?? item
+              const recordId = String(item?.id ?? attrs?.id ?? '')
+              recs.push(new DatasetRecord(
+                attrs?.input ?? null,
+                attrs?.expected_output ?? null,
+                attrs?.metadata ?? {},
+                recordId === '' ? null : recordId
+              ))
+              ids.push(recordId)
+            }
           }
           cursor = resp?.meta?.after ?? ''
           if (!cursor) break
diff --git a/packages/dd-trace/src/llmobs/experiments/util.js b/packages/dd-trace/src/llmobs/experiments/util.js
index 9236f9098c7..002b0c98519 100644
--- a/packages/dd-trace/src/llmobs/experiments/util.js
+++ b/packages/dd-trace/src/llmobs/experiments/util.js
@@ -166,8 +166,10 @@ function stringify (value) {
  */
 function buildTags (userTags, autoTags) {
   const tags = new Map()
-  for (const [key, value] of Object.entries(userTags ?? {})) {
-    tags.set(key, `${key}:${value}`)
+  if ((userTags) != null) {
+    for (const [key, value] of Object.entries(userTags)) {
+      tags.set(key, `${key}:${value}`)
+    }
   }
   for (const [key, value] of Object.entries(autoTags)) {
     if (value !== undefined && value !== null && value !== '') tags.set(key, `${key}:${value}`)
diff --git a/packages/dd-trace/src/sampling_rule.js b/packages/dd-trace/src/sampling_rule.js
index 04787057033..28b82c771d6 100644
--- a/packages/dd-trace/src/sampling_rule.js
+++ b/packages/dd-trace/src/sampling_rule.js
@@ -180,8 +180,10 @@ class SamplingRule {
     if (resource) {
       this.matchers.push(matcher(resource, resourceLocator))
     }
-    for (const [key, value] of Object.entries(tags || {})) {
-      this.matchers.push(matcher(value, makeTagLocator(key)))
+    if (tags) {
+      for (const [key, value] of Object.entries(tags)) {
+        this.matchers.push(matcher(value, makeTagLocator(key)))
+      }
     }
 
     this._sampler = new Sampler(sampleRate)
diff --git a/packages/dd-trace/src/telemetry/telemetry.js b/packages/dd-trace/src/telemetry/telemetry.js
index af6f5d37b76..cce74abb312 100644
--- a/packages/dd-trace/src/telemetry/telemetry.js
+++ b/packages/dd-trace/src/telemetry/telemetry.js
@@ -130,7 +130,7 @@ function updateRetryData (error, retryObj) {
 
 function getIntegrations () {
   const newIntegrations = /** @type {Integration[]} */ ([])
-  for (const pluginName of Object.keys(pluginManager._pluginsByName ?? {})) {
+  for (const pluginName of Object.keys(pluginManager._pluginsByName)) {
     if (!sentIntegrations.has(pluginName)) {
       newIntegrations.push({
         name: pluginName,
diff --git a/scripts/check_licenses.js b/scripts/check_licenses.js
index c54f95b30ff..13fb872a120 100644
--- a/scripts/check_licenses.js
+++ b/scripts/check_licenses.js
@@ -203,16 +203,18 @@ function addNpmProductionDependencies (dependencies, packageLockPath) {
 function addDependencyPatterns (patterns, manifest, context, includePeers = false) {
   const optionalDependencies = manifest.optionalDependencies ?? {}
 
-  for (const [name, range] of Object.entries(manifest.dependencies ?? {})) {
-    if (!Object.hasOwn(optionalDependencies, name)) {
-      addDependencyPattern(patterns, name, range, context)
+  if ((manifest.dependencies) != null) {
+    for (const [name, range] of Object.entries(manifest.dependencies)) {
+      if (!Object.hasOwn(optionalDependencies, name)) {
+        addDependencyPattern(patterns, name, range, context)
+      }
     }
   }
   for (const [name, range] of Object.entries(optionalDependencies)) {
     addDependencyPattern(patterns, name, range, context)
   }
-  if (includePeers) {
-    for (const [name, range] of Object.entries(manifest.peerDependencies ?? {})) {
+  if (includePeers && (manifest.peerDependencies) != null) {
+    for (const [name, range] of Object.entries(manifest.peerDependencies)) {
       addDependencyPattern(patterns, name, range, context, manifest.optionalPeers?.includes(name))
     }
   }
diff --git a/scripts/generate-config-types.js b/scripts/generate-config-types.js
index 235a07a1f62..418f5d49fdc 100644
--- a/scripts/generate-config-types.js
+++ b/scripts/generate-config-types.js
@@ -253,9 +253,11 @@ function generateEnvVarConfigTypes (supportedConfigurations) {
     const type = getEnvVarType(propertyName, entry)
 
     envVarTypes.set(canonicalName, type)
-    for (const alias of entry.aliases ?? []) {
-      if (!supportedConfigurations[alias] && !envVarTypes.has(alias)) {
-        envVarTypes.set(alias, type)
+    if ((entry.aliases) != null) {
+      for (const alias of entry.aliases) {
+        if (!supportedConfigurations[alias] && !envVarTypes.has(alias)) {
+          envVarTypes.set(alias, type)
+        }
       }
     }
   }
diff --git a/scripts/generate-supported-integrations.js b/scripts/generate-supported-integrations.js
index f8958cd156c..db877961872 100644
--- a/scripts/generate-supported-integrations.js
+++ b/scripts/generate-supported-integrations.js
@@ -108,9 +108,11 @@ function readInstrumentationRanges (engines) {
  */
 function lowestVersion (ranges) {
   let lowest
-  for (const range of ranges ?? []) {
-    const candidate = semver.minVersion(range)
-    if (candidate && (!lowest || semver.lt(candidate, lowest))) lowest = candidate
+  if ((ranges) != null) {
+    for (const range of ranges) {
+      const candidate = semver.minVersion(range)
+      if (candidate && (!lowest || semver.lt(candidate, lowest))) lowest = candidate
+    }
   }
   return lowest?.version ?? ''
 }
diff --git a/scripts/mocha-run-file.js b/scripts/mocha-run-file.js
index 51c083ba694..741baa49f36 100644
--- a/scripts/mocha-run-file.js
+++ b/scripts/mocha-run-file.js
@@ -67,11 +67,13 @@ async function main () {
     reporterOptions: config.reporterOptions,
   })
 
-  for (const req of config.require ?? []) {
-    // Resolve relative to repo root (cwd), matching Mocha CLI behavior.
-    const mod = require(path.resolve(req))
-    if (mod?.mochaHooks) {
-      mocha.rootHooks(mod.mochaHooks)
+  if ((config.require) != null) {
+    for (const req of config.require) {
+      // Resolve relative to repo root (cwd), matching Mocha CLI behavior.
+      const mod = require(path.resolve(req))
+      if (mod?.mochaHooks) {
+        mocha.rootHooks(mod.mochaHooks)
+      }
     }
   }
 
diff --git a/yarn.lock b/yarn.lock
index 6fdd6c5e87f..b116865b23d 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2068,10 +2068,10 @@ eslint-plugin-sonarjs@^4.2.0:
     typescript ">=5 <6.1.0"
     yaml "^2.9.0"
 
-eslint-plugin-unicorn@^72.0.0:
-  version "72.0.0"
-  resolved "https://registry.yarnpkg.com/eslint-plugin-unicorn/-/eslint-plugin-unicorn-72.0.0.tgz#3d8caf428fd84c02457e6f152128fd1944ce19a9"
-  integrity sha512-hqO6ksoOHO+ZhdseTuKRVQbx9U7PRO/cv8qAR1mctwzdVO2hYud8uS9luAhp43RJgziYgHAph8eHyipT8GL0ng==
+eslint-plugin-unicorn@^73.0.0:
+  version "73.0.0"
+  resolved "https://registry.yarnpkg.com/eslint-plugin-unicorn/-/eslint-plugin-unicorn-73.0.0.tgz#665a56b95b4fdae0e1e72ee66dab38c6dd0260ba"
+  integrity sha512-V0YatLe9nkGhXEXKe2Qljb1EY0sJHwDV0HUF1NKFwtsHh/fU7qGHDgv+6fchzZcgU2/7noHo2gdjnmo0P2uDPw==
   dependencies:
     "@eslint-community/eslint-utils" "^4.9.1"
     "@eslint/css-tree" "^4.0.4"