April 2026 (2026-04) monthly summary for Mullvadvpn-app. Key features delivered include hardware-backed Android signing and build pipeline hardening. Major bugs fixed included corrections to reproducible diffs and signing-related issues, improving reliability and security. Overall impact: stronger security posture for Android builds, more reliable releases, improved CI/CD efficiency, and better traceability of changes. Technologies and skills demonstrated: Android container tooling, YubiKey PKCS#11 integration, PCSC, Gradle and Nix-based build pipelines, secure signing workflows, and devshell workflows for Android development.

March 2026 focused on reliability, security, and clarity in the Mullvad VPN app deployment and distribution workflow. Key improvements reduced risk in artifact uploads, hardened build scripts, and improved documentation to reduce developer confusion. The changes supported faster releases with fewer post-release incidents and clearer integration points for partners.

November 2025 (mullvadvpn-app) — Key features delivered and fixes across the project, with a focus on more predictable builds and safer releases. Key features delivered: 1) Default WireGuard implementation switched to gotatun/boringtun in cargo, removing wireguard-go from default builds and exposing an option to re-enable userspace wireguard via TALPID_FORCE_USERSPACE_WIREGUARD. 2) Android/desktop build tooling and CI/docs updates, including cleanup of Go tooling, removal of Go/WGGo from Android builds, and moving Android build instructions to docs. 3) Versioning and Play publishing enhancements: refactored version logic to a Gradle provider, added conditional and automatic Play publishing, and introduced stable/beta version helpers. 4) Nix configuration refactor and shared config: extracted common nix config and modernized workflows, channels, and devshell usage. 5) Deployment governance: Production publishing restricted to drafts to prevent unintended production releases. Major bugs fixed: 1) Windows binaries check now conditionally runs based on gotatun/borgintun or wireguard-go presence. 2) Nix/flake-related reproducibility checks and lockfile bumps ensure reproducible builds. 3) Android nix/development tooling cleanups improved CI reliability. Overall impact and accomplishments: Reduced deployment surface, improved build reproducibility and governance, accelerated release readiness, and stronger alignment with platform-specific defaults. Technologies/skills demonstrated: Rust/Cargo feature management, Gradle build automation, Android/Nix tooling, CI workflows, reproducible builds, and release governance.

Month 2025-10 focused on stabilizing cross‑platform builds, modernizing dev environments, and tightening Android CI/CD, while expanding developer guidance. Key cross‑repo outcomes include fixing a macOS build failure for protoc-gen-grpc-java by applying autoPatchelfHook only on Linux in nixpkgs, reducing platform regressions and improving CI reliability. In mullvadvpn-app, the Nix build environment was refreshed to align with upstream fixes, Python dependency issues were resolved by selecting an available Python 3 version, and Android CI/CD was streamlined through a self‑hosted runner and workflow updates, plus removal of obsolete patches. Additional momentum was gained by upgrading the Android Gradle plugin submodule to support JVM Toolchain 17 and by enriching developer docs for Android SDK/NDK and tooling. These efforts collectively improved build reliability, shortened iteration cycles, and lowered maintenance burden, delivering tangible business value through faster, more predictable releases and enhanced developer productivity.

July 2025 performance-focused update for mullvadvpn-app. Delivered a set of targeted enhancements that improve CI reliability, cross-platform developer workflows, security, and developer-facing documentation, resulting in more predictable releases and faster iteration cycles. The work spans reproducible CI, devshell tooling across Android and macOS, system gRPC plugin support, security hardening for credentials and keystores, and expanded build/docs guidance.

June 2025 milestones for mullvadvpn-app: 1) CI/CD Security Updates: added Karl's GPG key to the CI keys directory to strengthen code signing and integrity checks in the CI pipeline (commit 92bb48608f07020e40b12ae858bcab6445c50ffb). 2) Release Process Improvements and Alpha Publishing: improved release preparation UX with clearer headers and spacing and enabled alpha publishing by introducing a release configuration and wiring it into the build script's publishing tasks (commits dd978e5e426a7888d5dd2d223d94863ebc6a5051; e7196f194d481bba95f1f65ba02e86013eb78581). 3) Release Process Robustness and Correctness: added safeguards to the release preparation script to ensure the relay list exists before committing and only commits when changed; enforce that version information files are actually modified to prevent stale releases (commits 1e692852b0bd7e6f255f767ddd82c918f0851a03; ed7b5dd567b364f0a9cdde94aea079e8e8108fa3).

May 2025 — Mullvad Mullvadvpn-app: Security scanning improvements, CI automation, and release engineering that reduce risk, improve build determinism, and speed up release cycles. Delivered OSV-Scanner improvements to reduce false positives, extended ignore windows to maintain stable configurations through 2025-08-01, extended reproducible build triggers in CI, added APK permissions check to catch unintended dependency changes, and optimized Gradle build performance with parallel execution and config-cache-friendly refactors. Release readiness was advanced with Beta 1 and Beta 2 prep and final 2025.4 stable release, plus manifest permissions snapshot documentation.

April 2025 (mullvadvpn-app) — Key outcomes: Delivery of a structured Android release cadence and quality improvements, plus strengthened test stability. Established a clear path for beta and stable releases (2025.2-beta2, 2025.2, 2025.3), accelerated build times with Gradle caching while enforcing official Kotlin code style, and re-enabled end-to-end leak tests to validate leak detection after VPN settings UI changes. These efforts reduce release risk, shorten feedback loops, and improve overall product quality for Android users.

2025-03 Mullvad Mullvadvpn-app monthly summary focusing on business value and technical achievements across release readiness, CI/CD automation, security compliance, and reliability improvements. This period delivered release-ready Android versioning, enhanced automated publishing for devmole builds, tightened security posture with MASA documentation and CVE handling, and stabilized testing/build tooling to reduce risk and manual toil, accelerating release velocity and developer productivity.

February 2025 — Mullvadvpn-app: Security, CI/CD reliability, E2E testing improvements, and build/dependency governance across the Android project. Delivered targeted upgrades to vulnerability scanning, CI quality gates, end-to-end testing reliability, and library/version management, driving reduced risk, more stable builds, and clearer dependency governance.

January 2025 (2025-01) monthly summary for mullvad/mullvadvpn-app. Focus this month was to harden build integrity, streamline Android build flows, improve end-to-end (E2E) testing reliability, and tighten CI security, delivering concrete business value through reproducible builds, faster turnaround, and higher test confidence. Key features delivered: - Build Integrity and Reproducibility: Added build checksums output and ensured reproducible builds by removing user-specific path information in go build; aligned Rust remapping for target directory. Commits: 1812ba2a62126321111bafe62b998b3bcc2a2078; ef51904ca8ae8b16c8b5b39a204855f852d983e5; 4e270b2893232551c68f5d21b63796e7de9aa0be. - Android Build System Cleanup: Clean up libwg Android.mk by removing unused environment variables related to Go build architecture, OS, and tarball URLs to simplify the build process. Commit: 21649a41335f24b62aa80357bd02e2c49b8055d7. - End-to-End Testing Framework Enhancements and Reliability: Default E2E tests toward stagemole; added infra flavor control; improved API client error handling for 429; switched to partner API for account creation; enabled test attachments; refactored leak tests and fixed related assertions. Commits: a928adaf65c71c11c8b9c7752dd16a74f98d2154; 0a10a1ae2315f00a345263a4e9b8698e14cf713a; 2f615a48d78650a25a86bee6e50a945266dad3a0; b8ecbe5a43fb665e82686daf84fe46e0f9e601b3; 4f8d72d4d79e20162b5210d4ed5d7e8717a716f1; 406e3d3682d3bffd487fd0ee695d7aa30b0f7515; e9d051073ee57c27a96246eae03127ce6b503dad. - CI Workflow Security Improvements: Refactor CI workflow to use secrets for the debug keystore, removing dynamic generation and improving security. Commit: ff2e3422c79da34e212f58b25dfd932661c57578. Major bugs fixed: - Resolved missing default infra workflow variable to ensure consistent E2E execution. Commit: 0a10a1ae2315f00a345263a4e9b8698e14cf713a. - Fixed incorrect assertion by inverting it in E2E leak tests to improve reliability. Commit: e9d051073ee57c27a96246eae03127ce6b503dad. Overall impact and accomplishments: - Significantly improved build reliability and reproducibility, reducing environment-specific failures and enabling faster, repeatable releases. - Streamlined Android build process, decreasing friction for developer onboarding and CI runs. - Increased confidence in E2E tests through default-enabled tests, robust error handling, reliable account creation flows, test artifacts, and improved leak detection. - Strengthened security posture of CI/CD by removing runtime keystores from code paths and storing them as secrets. Technologies and skills demonstrated: - Go build optimizations and remapping for reproducible builds; Rust target-dir remapping. - Android.mk simplification and Makefile hygiene. - End-to-end testing engineering: API client resilience, test automation pipelines, leak testing, and artifacts handling. - CI/CD security: secret management and keystore handling. - Cross-discipline collaboration across build, test, and security domains.

December 2024 monthly performance summary for mullvad/mullvadvpn-app focusing on delivering security, privacy, release discipline, and code quality improvements. Business value delivered includes strengthened device security, enhanced user privacy, stable release processes, and a more scalable localization/CI workflow. Key achievements: - Android 2024.9 Release: Encrypted DNS Proxy and security enhancements with changelog updates and version bump (beta release). - Multihop Routing feature and DAITA UI/Translation upgrades: privacy improvements with updated UI text and translations and changelog entries. - Android 2024.10 Release: beta1/beta2 with UI bug fix (filter screen) and version bumps, including multihop notes. - Maintenance & CI/Code Quality Improvements and i18n Infrastructure: CI lint optimizations scoped to app module, lint baseline generation, and i18n tooling upgrades; translation updates and messages.pot refreshed. - Localization readiness and governance: translation baseline and prepare-script adjustments to stabilize translations and release notes for upcoming cycles.

November 2024: Delivered security mitigations, streamlined release processes, and enhanced Play Store publishing for the Mullvad VPN Android app. Key outcomes include CVE-2024-47535 mitigation reducing Windows exposure risk; enabling internal/testing Play Store publishing via Gradle publish plugin with stage/mole flavors and CI integration; and tightening the Android build workflow to support a stable release (version 2024.8). These changes improve security posture, accelerate internal testing and deployment, and strengthen release reliability. Technologies demonstrated include Gradle plugin usage, Android Gradle build system, flavor-based publishing, CI/CD automation, and versioning discipline.

October 2024 focused on expanding platform coverage, tightening security posture, and improving Android stability and documentation for Mullvad VPN app. Delivered cross-platform enhancements for DAITA, mitigated CVE-2022-24329 risk with no code changes, and published actionable Android release notes and stability fixes to support customers and contributors.