[oharboe]

Before: the installer installed the KLayout application on every OS, because the flow wrote its GDS file and ran its DRC/LVS decks with it.
Now: the installer installs no KLayout application; the flow needs only KLayout's Python module, which #4757 brings in with the other Python packages.

Draft, and red until #4757 merges. This pull request does not contain #4757: on master the GDS merge still runs under the KLayout application, so without it the flow stops at the merge. Once #4757 is in master, pr-merge runs this on top of it and goes green; then this comes out of draft. It merges cleanly on top of #4757 (git merge-tree).

Deleted

• etc/DependencyInstaller.sh: klayoutVersion and the KLayout install for each OS:
  • the version-check-and-reinstall logic, written three times (CentOS 7, CentOS 8, Rocky Linux 9) around klayout.org RPMs;
  • on Ubuntu x86_64, the klayout.org .deb download, its md5 table per release, and the "Unsupported Ubuntu version" exit, so KLayout's packaging no longer limits which Ubuntu releases the installer supports;
  • on Ubuntu aarch64, the build of KLayout from source with its Qt, Ruby and libgit2 build dependencies, the slowest step of a fresh aarch64 install;
  • klayout from apt on rodete, and the Homebrew cask on macOS.
• env.sh: the KLayout.app PATH entry on macOS.
• flow/scripts/variables.mk: the lookup of a KLayout in tools/install/klayout, which nothing installs. KLAYOUT_CMD is the klayout on PATH unless set.
• docs/user/BuildWithPrebuilt.md: the KLayout version note and the LD_LIBRARY_PATH line for a KLayout built from source; it now says the GDS file, DRC and LVS use the Python module.

Still needing the KLayout application

A deprecated Ruby DRC/LVS deck (unsupported after 2027-02-06, #4757), the gallery and the viewers. Whoever uses them installs it; without it they stop at check-klayout, as on master.

Tests

• bash -n etc/DependencyInstaller.sh; make -n parses on asap7/gcd.
• Everything the flow runs without the application is tested in flow: KLayout Python module for GDS, DRC and LVS; deprecate Ruby decks; no KLayout application install #4757.

🤖 Generated with Claude Code

https://claude.ai/code/session_018PFLaCzFtFbnWE4nPTDwpC

[gemini-code-assist]

Code Review

This pull request simplifies the KLayout installation process by removing custom build and dependency management logic from the installation scripts and Makefiles, relying instead on system-provided packages. The review comment identifies a performance issue in the Makefile where the use of a deferred shell expansion for the KLayout command causes unnecessary shell spawning; it suggests a more efficient way to define the variable.

[oharboe]

Folded into #4757 as its last commit, installer: no KLayout application: with Ruby decks deprecated, the ORFS installer installs only the klayout Python module, and whoever uses a Ruby deck installs the KLayout application themselves.

[openroad-ci]

🔍 QoR check

Metrics reflect the PR merge build — i.e. what will land on the target branch.

Commit 7d81988 · Jenkins build #1 · Baseline: none resolved · View build on dashboard

62 design(s) checked — 0 with regression(s), 62 without a comparable baseline.