March 2026 monthly summary for the openai/codex repository focused on Windows sandbox reliability, sandbox configuration, and release automation. These changes improve reliability, determinism, and distribution efficiency for Windows users, and lay groundwork for safer sandbox usage and faster delivery of Codex CLI updates.

February 2026 performance highlights: Strengthened sandbox isolation, observability, and release reliability across Codex products. Delivered UAT Cancellation Metrics and per-workspace capability SIDs in zed-industries/codex to improve analytics and isolation. Enhanced telemetry with real OS data and sandbox policy tagging, improving visibility into OS-level performance and sandbox usage. Expanded Windows Sandbox UX and policy controls (read access, security hardening) in openai/codex, plus app-server support for Windows sandbox setup. Fixed release reliability with NPM Publish Robustness. Also added sandbox helpers for the OpenAI Codex 0.94 installer in winget-pkgs. These efforts reduce risk in multi-tenant environments, enhance troubleshooting, and accelerate safe deployments.

January 2026: Security hardening, UX enhancements, packaging improvements, and expanded observability for Codex Windows Sandbox. Delivered group-based Sandbox ACLs via SandboxUsers, privacy improvements to reduce exposure of sandbox accounts, and a comprehensive Elevated Sandbox UX with prompts and a dedicated /elevate-sandbox flow. Strengthened data protection by restricting sandbox directory writes and adopting system SIDs for locale-robust setups. Improved reliability with firewall rule idempotency, DPAPI machine scope, and packaging fixes for Winget and dist bundles. Expanded telemetry, including sandbox setup metrics, NUX events, and failure diagnostics for PowerShell spawning. Also enabled elevated sandbox without the base experimental flag. These changes improve security, usability, localization compatibility, distribution readiness, and operational visibility.

December 2025: Delivered a multi-release cycle for the Elevated Sandbox suite in codex, establishing a robust foundation for secure sandbox operations, while improving CI reliability and packaging for Windows. Focused on security, stability, and deployment readiness, with enhancements across sandbox setup, password handling, binaries, signing, and artifact workflows. The month set up a scalable architecture for sandbox binaries, improved ACL handling and logging, and tightened build/test pipelines to reduce CI failures, enabling a smoother upgrade path to Elevated Sandbox 4 and beyond.

November 2025 (2025-11) monthly summary for zed-industries/codex focused on Windows Sandbox hardening, world-writable risk controls, and Windows distribution readiness. Delivered key sandbox reliability improvements (trust prompt correctness and command logging), enhanced world-writable scanning (speed, broader coverage, and reduced false positives), introduced Winget packaging workflow templates and Windows CLI release artifacts to enable reliable distribution, and improved sandbox UX with auto-mode prompts and multi-root workspace support. These changes reduce security risk, accelerate Windows deployments, and improve reliability for enterprise environments.

2025-10 Monthly Summary (two repos: zed-industries/codex and openai/codex). This period focused on tightening security, improving Windows UX, enabling safer workflows, and enhancing terminal and model experiences. Key features delivered include Windows-specific safety, sandboxing, WSL onboarding, and targeted UI/UX improvements for Windows paths and terminal visuals. Major reliability improvements were achieved through added tests and robustness fixes, contributing to safer, more predictable developer workflows across Windows environments.

September 2025 monthly performance snapshot focused on strengthening command safety, cross-environment risk controls, and code quality across two active codex repos. Delivered policy-driven safety features, expanded cross-shell checks, and maintained clear documentation, with measurable business value in risk reduction, governance, and maintainability.