Kotlin Tooling Cocoapods Spm Migration

CocoaPods to SwiftPM Migration for KMP

Migrate Kotlin Multiplatform projects from kotlin("native.cocoapods") to swiftPMDependencies {} DSL.

Requirements

• Kotlin: Version with Swift Import support (e.g., 2.4.0-Beta1 or later)
• Xcode: 16.4 or 26.0+
• iOS Deployment Target: 16.0+ recommended

Migration Overview

IMPORTANT: Keep the cocoapods {} block and plugin active until Phase 6. The migration adds swiftPMDependencies {} alongside the existing CocoaPods setup first, reconfigures Xcode, and only then removes CocoaPods.

Phase 1: Pre-Migration Analysis

1.0 Verify the project builds

Before starting migration, identify the module to migrate and confirm it compiles successfully.

1. Find the module that uses CocoaPods — look for build.gradle.kts files containing cocoapods:

   bashCopy code
   grep -rl "cocoapods" --include="build.gradle.kts" .
   

   Extract the module name from the path (e.g., ./shared/build.gradle.kts → module name is shared).

2. Build only that module (avoids building the entire multi-module project):

   bashCopy code
   ./gradlew :moduleName:build
   

   Replace moduleName with the directory name of the module (e.g., :shared:build).

3. If the targeted build fails, ask the user to either:

   • Provide the correct Gradle command to verify the module builds, or
   • Confirm the module is in a working state and it's safe to proceed

   If the user confirms without providing a build command, record that the pre-migration build could not be verified and warn about this at the end of migration (Phase 7).

1.0a Confirm Kotlin version with Swift Import support

Ask the user:

Does your project already use a Kotlin version with Swift Import support (swiftPMDependencies DSL)?

If yes → read their current Kotlin version from gradle/libs.versions.toml (or build.gradle.kts), record it, and skip Phase 2.2 (no version change needed).

If no → ask:

Please provide the Kotlin version to use (e.g., "2.4.0", "2.4.0-Beta1", "2.4.0-dev-123").

Record the user-provided version. Then ask:

Does this Kotlin version require a custom Maven repository (e.g., JetBrains dev repo)?

• Yes → ask for the repo URL (suggest https://packages.jetbrains.team/maven/p/kt/dev as default). Phase 2.1 will add it.
• No → Phase 2.1 is skipped (no custom repo needed).

Finally, check the project's current Kotlin version. Compare major.minor against the target. If it differs significantly (e.g., 2.1.0 → 2.4.0), warn: "⚠️ Kotlin version jump — upgrading across minor versions can introduce breaking changes unrelated to this migration. Recommended: update first, verify it builds, then re-run." If the user confirms despite the mismatch, proceed.

1.1 Check for deprecated CocoaPods workaround property

Search gradle.properties for the deprecated property:

propertiesCopy code
kotlin.apple.deprecated.allowUsingEmbedAndSignWithCocoaPodsDependencies=true

This property was a workaround (see KT-64096) for projects using embedAndSign alongside CocoaPods dependencies. It suppresses an error about unsupported configurations that can cause runtime crashes or symbol duplication. After migrating to SwiftPM import, this property is no longer needed and must be removed in Phase 6. Record its presence if found.

1.2 Check for EmbedAndSign disablers

Search all build.gradle.kts files for code that disables EmbedAndSign tasks (e.g., TaskGraph.whenReady filters, tasks.matching blocks). This is a CocoaPods-era workaround that breaks the migration because integrateEmbedAndSign (needed in Phase 5) gets disabled too. Record any such code — it must be removed in Phase 6, and may need to be removed earlier. See troubleshooting.md § "integrateEmbedAndSign Skipped" for patterns.

1.3 Check for third-party KMP libraries with bundled cinterop klibs

Some KMP libraries ship pre-built cinterop klibs with cocoapods.* package namespaces. After migration, the swiftPMDependencies cinterop generator detects these existing bindings and skips generating new bindings for those Clang modules to avoid duplicates. This means cocoapods.* imports for those modules must be kept as-is — they resolve to the third-party library's bundled klib, not to actual CocoaPods.

Known libraries with bundled cocoapods.* klibs:

How to detect: Search Gradle dependency declarations for known libraries, then cross-reference their bundled namespaces against the import cocoapods.* statements found in step 4. Mark any matches — these imports will NOT be transformed in Phase 4.

If unsure whether a third-party KMP library bundles cinterop klibs, check if it has a linkOnly = true pod dependency in the project — this is a strong indicator that the library provides its own klib for those classes.

To inspect klib contents and verify bundled bindings, see troubleshooting.md § "Third-Party KMP Libraries with Bundled Klibs".

Find and record:

1. CocoaPods configuration - Search for cocoapods in build.gradle.kts files
2. Pod dependencies - Extract pod names, versions from cocoapods {} blocks
3. Framework configuration - Record baseName, isStatic, deployment target from cocoapods.framework {}
4. linkOnly pods - Record pods declared with linkOnly = true. These pods provide native linking only — cinterop bindings come from a KMP wrapper library (e.g., dev.gitlive:firebase-*). See common-pods-mapping.md for implications.
5. Kotlin imports - Find all import cocoapods.* statements. Cross-reference with step 1.3 to identify which imports come from bundled klibs (and must be preserved) vs. which come from direct pod cinterop (and must be transformed).
6. Map pods to SPM - See common-pods-mapping.md
7. Locate iOS project directory - Find the directory containing Podfile and .xcworkspace:

   bashCopy code
   find . -name "Podfile" -type f
   

   Record this path (e.g., iosApp/, ios/, or project root) - needed for Phase 5
8. Check for non-KMP CocoaPods - Determine if the project uses CocoaPods for dependencies other than KMP. This affects cleanup strategy in Phase 5.
9. Check Xcode build phases - Open the .xcodeproj's project.pbxproj and search for the Gradle build phase script. Check if embedAndSignAppleFrameworkForXcode is present but commented out (prefixed with #). If commented out, it must be uncommented during Phase 5 — the integrateEmbedAndSign task may or may not handle this automatically.
10. Check for existing Crashlytics dSYM upload script - If using FirebaseCrashlytics, search project.pbxproj for a dSYM upload shell script phase. Record its current path (CocoaPods-era scripts reference ${PODS_ROOT}/FirebaseCrashlytics/upload-symbols). This must be updated to the SPM path in Phase 5.
11. Identify CocoaPods-related extras in build scripts - Search all build.gradle.kts files for CocoaPods workarounds beyond the standard cocoapods {} block (custom tasks hooking into podInstall, Pods.xcodeproj patching, podspec metadata, extraSpecAttributes, noPodspec(), etc.). See cocoapods-extras-patterns.md for the full pattern list. Record all findings — these will be handled in Phase 6.

Phase 2: Gradle Configuration

Important scope note: Do NOT upgrade the Gradle wrapper version, update KSP, or update any other dependencies during this migration. Those are separate concerns and out of scope. Only change what is listed below.

2.1 Add custom Maven repository (if needed)

Skip this step if the user indicated in Phase 1.0a that their Kotlin version does not require a custom Maven repository (i.e., it is an official release, Beta, or RC available from Maven Central).

For dev/custom builds, add the custom Maven repository (URL from Phase 1.0a) to settings.gradle.kts:

kotlinCopy code
pluginManagement {
    repositories {
        gradlePluginPortal()
        mavenCentral()
        maven("<custom-repo-url>")  // ADD
    }
}

dependencyResolutionManagement {
    repositories {
        mavenCentral()
        maven("<custom-repo-url>")  // ADD
    }
}

2.2 Update Kotlin version

Skip this step if the user's project already uses a Kotlin version with Swift Import support (recorded in Phase 1.0a).

Update to the version recorded in Phase 1.0a:

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# gradle/libs.versions.toml
[versions]
kotlin = "<kotlin-version>"

2.3 Add buildscript constraint (if swiftPMDependencies not recognized)

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// root build.gradle.kts
buildscript {
    dependencies.constraints {
        "classpath"("org.jetbrains.kotlin:kotlin-gradle-plugin:<kotlin-version>!!")
    }
}

Replace <kotlin-version> with the version recorded in Phase 1.0a. The !! suffix forces strict version resolution, ensuring no other dependency pulls in a different Kotlin Gradle plugin version.

Phase 3: Add swiftPMDependencies (Keep CocoaPods)

Do NOT remove the cocoapods {} block or kotlin("native.cocoapods") plugin yet. Add swiftPMDependencies {} alongside the existing CocoaPods configuration.

3.1 Add group property

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group = "org.example.myproject"  // Required for import namespace

3.2 Add swiftPMDependencies block alongside cocoapods

For each pod dependency, add the equivalent SwiftPM package declaration. Use common-pods-mapping.md to map each pod to its SPM package URL, product name, and importedModules.

Key concepts: products = SPM product names (controls linking). importedModules = Clang module names for cinterop bindings (only when discoverModulesImplicitly = false). discoverModulesImplicitly defaults to true (bindings for all Clang modules); set false when transitive C/C++ modules fail cinterop (Firebase, gRPC), then list needed modules explicitly.

Important: SPM product names and Clang module names don't always match. Always consult common-pods-mapping.md for correct values.

Do not mix the same library suite across CocoaPods and SPM. Libraries that share a common repository (e.g., all Firebase products) share transitive dependencies. Having some products linked via CocoaPods and others via SPM causes duplicate/conflicting symbols and dyld crashes at runtime. When migrating such a suite, move all pods from that suite to SPM at once — including Swift-only pods that Kotlin doesn't use directly. Add Swift-only pods as products entries (no importedModules needed). After adding new products, re-run integrateLinkagePackage to regenerate the linkage Swift package.

kotlinCopy code
kotlin {
    // Keep existing targets
    iosArm64()
    iosSimulatorArm64()
    iosX64()

    swiftPMDependencies {
        iosDeploymentVersion.set("16.0")

        // If using KMP IntelliJ plugin, specify the .xcodeproj path:
        // xcodeProjectPathForKmpIJPlugin.set(
        //     layout.projectDirectory.file("../iosApp/iosApp.xcodeproj")
        // )

        swiftPackage(
            url = url("https://github.com/owner/repo.git"),
            version = from("1.0.0"),
            products = listOf(product("ProductName")),
        )
    }

    cocoapods {
        // ... keep existing cocoapods block for now
    }
}

3.3 Move framework configuration out of cocoapods block

If the cocoapods block contains a framework {} configuration, move it to the binaries API on each target. isStatic = true is recommended — dynamic frameworks have known edge cases with SwiftPM import that can cause linker errors, dyld crashes, or duplicate class warnings:

kotlinCopy code
listOf(iosArm64(), iosSimulatorArm64(), iosX64()).forEach { iosTarget ->
    iosTarget.binaries.framework { baseName = "Shared"; isStatic = true }
}

3.4 Handle dev.gitlive/firebase-kotlin-sdk and similar CocoaPods-era KMP wrappers

If the project uses dev.gitlive:firebase-* or similar KMP wrapper libraries, two additional steps are required:

A. Switch to isStatic = true — dynamic frameworks + Firebase SPM = runtime dyld crash. After switching: re-run integrateLinkagePackage, remove any "Embed Frameworks" copy phase, move linker flags to OTHER_LDFLAGS.

B. Add framework search paths — add conditional -F linkerOpts in build.gradle.kts and matching FRAMEWORK_SEARCH_PATHS in the Xcode project.

See common-pods-mapping.md § dev.gitlive and troubleshooting.md for code snippets and the full product list.

3.5 Add opt-in for cinterop API

kotlinCopy code
kotlin.compilerOptions {
    optIn.add("kotlinx.cinterop.ExperimentalForeignApi")
}

For full DSL reference, see dsl-reference.md.

Phase 4: Kotlin Source Updates

Import Namespace Formula

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swiftPMImport.<group>.<module>.<ClassName>

Where:
- group: build.gradle.kts `group` property, dashes (-) → dots (.)
- module: Gradle module name, dashes (-) → dots (.)
- ClassName: Objective-C class name (FIR* for Firebase, GMS* for Google Maps)

Example Transformation

kotlinCopy code
// group = "org.jetbrains.kotlin.firebase.sample", module = "kotlin-library"

// BEFORE:
import cocoapods.FirebaseAnalytics.FIRAnalytics

// AFTER:
import swiftPMImport.org.jetbrains.kotlin.firebase.sample.kotlin.library.FIRAnalytics

Import flattening: The Clang module name (e.g., FirebaseFirestoreInternal, FirebaseAuth) disappears from the import path — all classes are flattened under the same swiftPMImport.<group>.<module> prefix regardless of which library they come from. For example, both cocoapods.FirebaseAuth.FIRAuth and cocoapods.FirebaseFirestoreInternal.FIRFirestore become swiftPMImport.<group>.<module>.FIRAuth and swiftPMImport.<group>.<module>.FIRFirestore.

Preserving Bundled Klib Imports

CRITICAL: Do NOT replace cocoapods.* imports that resolve to third-party KMP libraries' bundled cinterop klibs (identified in Phase 1 step 1.3). These imports must remain as-is — the cocoapods prefix is the package namespace in the library's published klib, not an actual CocoaPods dependency. The swiftPMDependencies cinterop generator skips modules already provided by a dependency's klib, so swiftPMImport.* for those classes will fail with "Unresolved reference".

Example (project using KMPNotifier):

kotlinCopy code
// KEEP — resolves to kmpnotifier's bundled cinterop klib
import cocoapods.FirebaseMessaging.FIRMessaging

Bulk Replacement

Use a regex find-and-replace across all Kotlin source files, excluding imports identified in Phase 1 step 1.3:

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Find:    cocoapods\.\w+\.
Replace: swiftPMImport.<your.group>.<your.module>.

After bulk replacement, manually restore any cocoapods.* imports that should be preserved (from bundled klibs).

Finding correct import path: Run ./gradlew :moduleName:build - errors show available classes.

Phase 5: iOS Project Reconfiguration

5.1 Get migration command

Build the CocoaPods workspace to obtain the migration command:

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cd /path/to/iosApp

xcodebuild -scheme "$(echo -n *.xcworkspace | python3 -c 'import sys, json; from subprocess import check_output; print(list(set(json.loads(check_output(["xcodebuild", "-workspace", sys.stdin.readline(), "-list", "-json"]))["workspace"]["schemes"]) - set(json.loads(check_output(["xcodebuild", "-project", "Pods/Pods.xcodeproj", "-list", "-json"]))["project"]["schemes"]))[0])')" -workspace *.xcworkspace -destination 'generic/platform=iOS Simulator' ARCHS=arm64 | grep -A5 'What went wrong'

The build output will contain a command like:

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XCODEPROJ_PATH='/path/to/project/iosApp.xcodeproj' GRADLE_PROJECT_PATH=':shared' '/path/to/project/gradlew' -p '/path/to/project' ':shared:integrateEmbedAndSign' ':shared:integrateLinkagePackage'

Run this command. It modifies the .xcodeproj to trigger embedAndSignAppleFrameworkForXcode during the build. integrateLinkagePackage is a one-time setup — it does not need to be added as a build phase. If integrateEmbedAndSign is skipped, check for EmbedAndSign disablers (Phase 1 step 1.2) — remove them first, then re-run.

Verify embedAndSignAppleFrameworkForXcode is active: After running integration, check the build phase script in project.pbxproj. If embedAndSignAppleFrameworkForXcode is commented out (prefixed with #), uncomment it.

The integrateLinkagePackage task generates _internal_linkage_SwiftPMImport/ at <iosDir>/ — a local Swift package that mirrors your products list and ensures SPM libraries are linked into the final binary.

After running the integration tasks, disable User Script Sandboxing (ENABLE_USER_SCRIPT_SANDBOXING = NO) in the .xcodeproj. Xcode 16+ enables it by default, which prevents the Gradle build phase from writing to the project directory:

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sed -i '' 's/ENABLE_USER_SCRIPT_SANDBOXING = YES/ENABLE_USER_SCRIPT_SANDBOXING = NO/g' "$XCODEPROJ_PATH/project.pbxproj"

If the setting is absent (Xcode defaults to YES), add ENABLE_USER_SCRIPT_SANDBOXING = NO; to the app target's buildSettings sections. Then restart the Gradle daemon: ./gradlew --stop

Alternative (if xcodebuild approach fails): See troubleshooting.md § "Manual Integration Command Discovery" for a fallback script to discover paths and run integration tasks directly.

5.2 Update Crashlytics dSYM upload script (if applicable)

If the project uses FirebaseCrashlytics and has a dSYM upload run script phase (identified in Phase 1 step 10), update the script path from ${PODS_ROOT}/FirebaseCrashlytics/upload-symbols to "${BUILD_DIR%/Build/*}/SourcePackages/checkouts/firebase-ios-sdk/Crashlytics/run". See troubleshooting.md § "Firebase Crashlytics: dSYM Upload Script" and common-pods-mapping.md for the full script and input files list.

5.3 Deintegrate CocoaPods

Option A: Full deintegration (if CocoaPods was used ONLY for KMP dependencies):

Before deleting files, run git status --short and verify the paths. If unsure, move files to a backup location instead of deleting immediately.

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cd /path/to/iosApp
pod deintegrate
rm -rf Podfile Podfile.lock Pods/
# Remove the workspace that matches your app xcodeproj name
XCODEPROJ_NAME=$(basename "$(find . -maxdepth 1 -name "*.xcodeproj" -type d | grep -v Pods | head -1)" .xcodeproj)
rm -rf "${XCODEPROJ_NAME}.xcworkspace"
# Return to project root
cd ..
# Remove the migrated module podspec only (for example, shared.podspec)
# If unknown, list candidates and remove the matching one explicitly:
ls -1 *.podspec
# rm -f shared.podspec

This cleanup snippet is self-contained and does not assume XCODEPROJ_PATH or GRADLE_PROJECT_PATH from the earlier one-off migration command are still available in your shell.

If pod deintegrate is not available, see troubleshooting.md § "Manual CocoaPods Deintegration from pbxproj" for the full list of references to remove. Also remove Pods/ from .gitignore and delete the .xcworkspace directory.

Option B: Partial removal (if other non-KMP CocoaPods dependencies remain):

Remove only the KMP pod line from the Podfile and re-run pod install:

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target 'iosApp' do
  # Remove this line:
  pod 'shared', :path => '../shared'
  # Keep other non-KMP pods
end

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cd /path/to/iosApp && pod install

Tip: Consider migrating remaining pods to SPM too — most popular iOS libraries support it natively. Add them in Xcode via File → Add Package Dependencies, then fully deintegrate CocoaPods once all pods are replaced.

5.4 Manual integration (if automatic fails)

See troubleshooting.md § "Manual Xcode Integration Steps" for the 5-step manual setup (build phase, sandboxing, linkage package).

Phase 6: Remove CocoaPods from Gradle

Now that the iOS project is reconfigured, remove the CocoaPods plugin and block:

6.1 Remove CocoaPods plugin

kotlinCopy code
plugins {
    // REMOVE: kotlin("native.cocoapods")
    alias(libs.plugins.kotlinMultiplatform)  // Keep
}

6.2 Remove cocoapods block

Delete the entire cocoapods { ... } block from build.gradle.kts. The swiftPMDependencies {} block and binaries.framework {} configuration added in Phase 3 replace it.

6.3 Remove deprecated gradle.properties entries

If found in Phase 1.1, remove from gradle.properties:

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# REMOVE — no longer needed after migrating away from CocoaPods (KT-64096)
kotlin.apple.deprecated.allowUsingEmbedAndSignWithCocoaPodsDependencies=true

6.4 Clean up CocoaPods-related extras

Review the extras identified in Phase 1 step 11. Podspec metadata, noPodspec(), CocoaPods task hooks, and Pods.xcodeproj patching code are safe to remove without user consultation. Non-standard pod configurations (extraOpts, moduleName), custom cinterop defFile setups, and CocoaPods-specific compiler/linker flags require analysis — consult the user if unsure whether SPM handles them automatically.

See cocoapods-extras-patterns.md for the full categorized list with examples.

Phase 7: Verification

7.1 Build Gradle project

Build the migrated module to verify the migration succeeded:

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./gradlew :moduleName:build

7.2 Link framework

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./gradlew :moduleName:linkDebugFrameworkIosSimulatorArm64

7.3 Build iOS/macOS Xcode project

After the Gradle build succeeds, build the Xcode project. Use -project *.xcodeproj if all CocoaPods were removed (Option A), or -workspace *.xcworkspace if non-KMP CocoaPods remain (Option B):

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cd /path/to/iosApp
# Discover schemes and build (replace -project/-workspace as needed; for macOS use -destination 'platform=macOS'):
xcodebuild -project *.xcodeproj -list -json 2>/dev/null | python3 -c "import sys,json; schemes=json.load(sys.stdin)['project']['schemes']; [print(s) for s in schemes]"
xcodebuild -project *.xcodeproj -scheme "<AppScheme>" -destination 'generic/platform=iOS Simulator' ARCHS=arm64 build

If checkSandboxAndWriteProtection fails — sandboxing was not disabled in Phase 5.1. Go back and apply the sandboxing fix from Phase 5.1, then retry.

If the pre-migration build was not verified (Phase 1.0 fallback was used), warn the user:

Note: The pre-migration build could not be fully verified. If build errors appear now, some may be pre-existing issues unrelated to the migration. Compare errors against the pre-migration build output to distinguish migration issues from prior problems.

If the build fails

Do NOT revert the migration. Read the error log, re-check Phases 2-6, and consult troubleshooting.md. If unsure, present options to the user — do not silently undo migration work.

Phase 8: Migration Report

After migration (whether successful or not), write a comprehensive MIGRATION_REPORT.md in the project root. Use the template in migration-report-template.md.

The report must include:

1. Pre-Migration State — CocoaPods dependencies (name, version, linkOnly), framework config, cocoapods.* imports, non-KMP pods, atypical configuration
2. Migration Steps — exact changes per phase with before/after snippets for non-trivial changes
3. Import Transformations — table of every import change, clearly marking preserved cocoapods.* imports and which bundled klib provides them
4. Errors Encountered — structured Error #N entries: phase, exact symptom, root cause, fix, generalizable flag
5. Non-Trivial Decisions — isStatic changes, preserved imports, framework search paths, trade-offs
6. Files Changed — complete list grouped by type (Gradle, Kotlin, Xcode, created, deleted)

Additional Resources

• DSL Reference - Full swiftPMDependencies syntax
• Common Pods Mapping - Pod to SPM mapping table
• CocoaPods Extras Patterns - Detection and cleanup patterns for CocoaPods workarounds
• Troubleshooting - Issues, solutions, rollback
• Migration Report Template - Post-migration report template