diff --git a/.editorconfig b/.editorconfig
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--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,27 @@
+# EditorConfig is awesome: https://EditorConfig.org
+
+# top-most EditorConfig file
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+# The POSIX standard requires the last line to end with a new line character.
+# All UNIX tools expect a new line at the end of files. Most text editors use this convention too.
+insert_final_newline = true
+trim_trailing_whitespace = true
+max_line_length = 120
+
+# Matches multiple files with brace expansion notation
+# Set default charset and 4 space indentation
+[*.{py,txt,md,rst,c,cxx,cpp,h,hpp,hxx,sh,cfg,ini}]
+indent_style = space
+indent_size = 4
+
+[*.{js,json,html,htm,xml,yaml,yml}]
+indent_style = space
+indent_size = 2
+
+# Tab indentation (no size specified)
+[{Makefile,*.go}]
+indent_style = tab
diff --git a/AGENTS.md b/AGENTS.md
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index 0000000..38ea467
--- /dev/null
+++ b/AGENTS.md
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+# AGENTS.md - Repository Guidelines for Agentic Coding
+
+## Build & Development Commands
+- `make help` - Show all available targets
+- `make dist` - Create source distribution in dist/
+- `make rpm` - Build RPM package
+- `make podman_rpm` - Build RPM using podman (for MacOS)
+- `make changelog` - Add changelog entry via ./changelog.sh
+- `make clean` - Clean generated files
+- Pre-commit hooks run automatically on commit (see .pre-commit-config.yaml)
+
+## Code Style Guidelines
+- **Shell Scripts**: Use bash syntax, source-safe with `${BASH_SOURCE-}` guard
+- **File Permissions**: profile.d scripts must be 0644 (install -m 0644) - they are sourced, not executed
+- **Line Endings**: LF only (enforced by pre-commit, see .editorconfig)
+- **No trailing whitespace** (enforced by pre-commit, see .editorconfig)
+- **Error Handling**: Use `command -v` instead of `which` for portability
+- **OS Compatibility**: Support both Linux and MacOS with conditional logic
+- **Naming**: Profile.d files use `z-<name>.sh` pattern for alphabetical loading
+- **Licensing**: The Unlicense unless explicitly stated otherwise
+- **Indentation**: 4 spaces for shell scripts (see .editorconfig)
+- **Large Files**: Max 64KB (enforced by pre-commit)
diff --git a/etc/profile.d/ssh_controlmasters.sh b/etc/profile.d/ssh_controlmasters.sh
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diff --git a/etc/profile.d/z-aliases.sh b/etc/profile.d/z-aliases.sh
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diff --git a/etc/profile.d/z-env.sh b/etc/profile.d/z-env.sh
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diff --git a/etc/profile.d/z-ps-twtty-7.sh b/etc/profile.d/z-ps-twtty-7.sh
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diff --git a/etc/profile.d/z-time_style.sh b/etc/profile.d/z-time_style.sh
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