rename: implement advertised backward-compat + prune dead community plugins

Address gaps where PR #537's "Backward compatibility" section was advertised
but not implemented, and clean up the community plugin list.

Env vars (FEEDBACK_* canonical, legacy SLOPSMITH_* honoured):
- New lib/env_compat.py (getenv_compat / env_flag_compat) + tests. server.py
  (_env_flag + all FEEDBACK_* reads), diagnostics_hardware, gp2midi and
  tailwind_rebuild now resolve the legacy alias, so existing SLOPSMITH_UI /
  SLOPSMITH_PLUGINS_DIR / etc. deployments keep working.
- Fix the rename collapsing plugins/__init__.py and minigames/routes.py from
  `FEEDBACK_PLUGINS_DIR or SLOPSMITH_PLUGINS_DIR` into a redundant
  `FEEDBACK_ or FEEDBACK_` (the fallback was silently lost).

Storage (app.js update-channel):
- Read feedBack-update-channel, fall back to legacy slopsmith-update-channel,
  and clear the legacy key on write — so a user's update-channel preference
  survives the rename instead of resetting to "stable".

Community plugin list (README): the rename rewrote third-party repo URLs we
don't own. Probed every one; their owners never renamed, so:
- Restore the 13 live community plugins to their real slopsmith-* names.
- Prune 6 that are 404 to the public (topkoa splitscreen/stems, OmikronApex
  tuner, Jafz2001 nam-rig-builder, DeathlySin song-preview, Erikcb91 shuffle).
- Fix a pre-existing Guitar Theory clone-command typo (nam-tone -> guitar-theory).

Verified: env_compat 7/7, JS 819/819, pytest 1690 collected / 0 import errors,
rename-sensitive + startup suites green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

README.md

@@ -15,34 +15,28 @@
 | [MIDI Amp Control](https://github.com/got-feedback/feedBack-plugin-midi)          | Auto-switch amp/modeler presets via MIDI on tone changes                                                                                                                                                                         | `git clone ...feedBack-plugin-midi.git midi_amp`                       |
 | [Section Map](https://github.com/got-feedback/feedBack-plugin-sectionmap)         | Color-coded song structure minimap with clickable navigation                                                                                                                                                                     | `git clone ...feedBack-plugin-sectionmap.git section_map`              |
 | [Arrangement Editor](https://github.com/got-feedback/feedBack-plugin-editor)      | DAW-like visual editor for creating and editing song note charts                                                                                                                                                                 | `git clone ...feedBack-plugin-editor.git editor`                       |
-| [MIDI Capo](https://github.com/masc0t/feedBack-plugin-midi-capo)                  | MIDI capo control for real-time transposition                                                                                                                                                                                    | `git clone ...feedBack-plugin-midi-capo.git midi_capo`                 |
+| [MIDI Capo](https://github.com/masc0t/slopsmith-plugin-midi-capo)                  | MIDI capo control for real-time transposition                                                                                                                                                                                    | `git clone ...slopsmith-plugin-midi-capo.git midi_capo`                 |
 | [Note Detection](https://github.com/got-feedback/feedBack-plugin-notedetect)      | Real-time pitch detection and scoring against highway notes                                                                                                                                                                      | `git clone ...feedBack-plugin-notedetect.git note_detect`              |
-| [Find More](https://github.com/masc0t/feedBack-plugin-find-more)                  | Search for more songs by the same artist                                                                                                                                                                                         | `git clone ...feedBack-plugin-find-more.git find_more`                 |
+| [Find More](https://github.com/masc0t/slopsmith-plugin-find-more)                  | Search for more songs by the same artist                                                                                                                                                                                         | `git clone ...slopsmith-plugin-find-more.git find_more`                 |
 | [Piano Highway](https://github.com/got-feedback/feedBack-plugin-piano)            | Scrolling piano/keyboard view for Keys arrangements with MIDI input                                                                                                                                                              | `git clone ...feedBack-plugin-piano.git piano`                         |
 | [Studio](https://github.com/got-feedback/feedBack-plugin-studio)                  | Collaborative band recording and multi-track mixing                                                                                                                                                                              | `git clone ...feedBack-plugin-studio.git studio`                       |
 | [Drum Highway](https://github.com/got-feedback/feedBack-plugin-drums)             | Lane-based drum highway with MIDI drum pad input and built-in sounds                                                                                                                                                             | `git clone ...feedBack-plugin-drums.git drums`                         |
-| [Split Screen](https://github.com/topkoa/feedBack-plugin-splitscreen)             | 2-4 highway panels side-by-side for multi-arrangement practice                                                                                                                                                                   | `git clone ...feedBack-plugin-splitscreen.git splitscreen`             |
+| [Invert Highway](https://github.com/masc0t/slopsmith-plugin-invert-highway)        | Flip the highway note direction                                                                                                                                                                                                  | `git clone ...slopsmith-plugin-invert-highway.git invert_highway`       |
-| [Stems Mixer](https://github.com/topkoa/feedBack-plugin-stems)                    | Per-stem mute/volume controls for .sloppak songs                                                                                                                                                                                 | `git clone ...feedBack-plugin-stems.git stems`                         |
+| [Jumping Tab](https://github.com/renanboni/slopsmith-plugin-jumpingtab)            | Yousician-style 2D horizontal tab with trajectory arcs and hopping ball                                                                                                                                                          | `git clone ...slopsmith-plugin-jumpingtab.git jumpingtab`               |
-| [Invert Highway](https://github.com/masc0t/feedBack-plugin-invert-highway)        | Flip the highway note direction                                                                                                                                                                                                  | `git clone ...feedBack-plugin-invert-highway.git invert_highway`       |
-| [Jumping Tab](https://github.com/renanboni/feedBack-plugin-jumpingtab)            | Yousician-style 2D horizontal tab with trajectory arcs and hopping ball                                                                                                                                                          | `git clone ...feedBack-plugin-jumpingtab.git jumpingtab`               |
 | [Step Mode](https://github.com/got-feedback/feedBack-plugin-stepmode)             | Step-by-step practice mode — highway freezes at each note until played (via Note Detection) or Space                                                                                                                             | `git clone ...feedBack-plugin-stepmode.git step_mode`                  |
 | [Lyrics Sync](https://github.com/got-feedback/feedBack-plugin-lyrics-sync)        | Generate synced LRC lyrics from text + vocals stem via Whisper alignment                                                                                                                                                         | `git clone ...feedBack-plugin-lyrics-sync.git lyrics_sync`             |
 | [Lyrics Karaoke](https://github.com/got-feedback/feedBack-plugin-lyrics-karaoke)  | Per-syllable karaoke pitch ribbon for sloppak songs (Whisper alignment + librosa pYIN)                                                                                                                                           | `git clone ...feedBack-plugin-lyrics-karaoke.git lyrics_karaoke`       |
 | [NAM Tone Engine](https://github.com/got-feedback/feedBack-plugin-nam-tone)       | In-browser amp modeling with NAM WASM, cabinet IRs, tone auto-switching                                                                                                                                                          | `git clone ...feedBack-plugin-nam-tone.git nam_tone`                   |
-| [Guitar Theory Lab](https://github.com/topkoa/feedBack-plugin-guitar-theory)      | Explore scales, chords, intervals, tunings, and voicings on a fully interactive fretboard                                                                                                                                        | `git clone ...feedBack-plugin-nam-tone.git guitar-theory-lab`          |
+| [Guitar Theory Lab](https://github.com/topkoa/slopsmith-plugin-guitar-theory)      | Explore scales, chords, intervals, tunings, and voicings on a fully interactive fretboard                                                                                                                                        | `git clone ...slopsmith-plugin-guitar-theory.git guitar-theory-lab`          |
-| [Themes](https://github.com/masc0t/feedBack-plugin-themes)                        | Offers several basic recolorings of the interface                                                                                                                                                                                | `git clone ...feedBack-plugin-themes.git themes`                       |
+| [Themes](https://github.com/masc0t/slopsmith-plugin-themes)                        | Offers several basic recolorings of the interface                                                                                                                                                                                | `git clone ...slopsmith-plugin-themes.git themes`                       |
-| [Update Manager](https://github.com/masc0t/feedBack-update-manager)               | Installs, updates, and uninstalls other plugins and the feedBack core itself                                                                                                                                                    | `git clone ...feedBack-update-manager.git update_manager`              |
+| [Update Manager](https://github.com/masc0t/slopsmith-update-manager)               | Installs, updates, and uninstalls other plugins and the feedBack core itself                                                                                                                                                    | `git clone ...slopsmith-update-manager.git update_manager`              |
-| [Tuner](https://github.com/OmikronApex/feedBack-plugin-tuner)                     | Floating tuner with customizable tunings                                                                                                                                                                                         | `git clone ...feedBack-plugin-tuner.git tuner`                         |
+| [Simplify Chords](https://github.com/bkranendonk/slopsmith-plugin-simplify-chords) | Changes complex chords on the note highway to simpler ones. Inspired by Ultimate Guitar's Simplify button.                                                                                                                       | `git clone ...slopsmith-plugin-simplify-chords.git simplify-chords`     |
-| [Simplify Chords](https://github.com/bkranendonk/feedBack-plugin-simplify-chords) | Changes complex chords on the note highway to simpler ones. Inspired by Ultimate Guitar's Simplify button.                                                                                                                       | `git clone ...feedBack-plugin-simplify-chords.git simplify-chords`     |
+| [Key Bindings](https://github.com/jackipicco/slopsmith-plugin-key-bindings)        | Highway key bindings for keyboard and TV remote                                                                                                                                                                                  | `git clone ...slopsmith-plugin-key-bindings.git key_bindings`           |
-| [Key Bindings](https://github.com/jackipicco/feedBack-plugin-key-bindings)        | Highway key bindings for keyboard and TV remote                                                                                                                                                                                  | `git clone ...feedBack-plugin-key-bindings.git key_bindings`           |
+| [Folder Organizer](https://github.com/Elit3d/slopsmith-plugin-folder-organizer)    | Organize your sloppak DLC songs into a folder tree view, grouped by subfolder name                                                                                                                                               | `git clone ...slopsmith-plugin-folder-organizer.git folder-organizer`   |
-| [Folder Organizer](https://github.com/Elit3d/feedBack-plugin-folder-organizer)    | Organize your sloppak DLC songs into a folder tree view, grouped by subfolder name                                                                                                                                               | `git clone ...feedBack-plugin-folder-organizer.git folder-organizer`   |
 | [Virtuoso](https://github.com/got-feedback/feedback-plugin-virtuoso)               | Practice studio for guitar & bass — scale, technique, and rhythm drills, timed workouts, and jam backing that teach skills you take off the screen.                                                                              | `git clone ...feedback-plugin-virtuoso.git virtuoso`                    |
-| [NAM Rig Builder](https://github.com/Jafz2001/feedBack-plugin-nam-rig-builder)    | Map tones to chained NAM neural-amp rigs (tone3000 captures + IRs) — full pedal→amp→cab playback, per-stage bypass, and a gear catalog                                                                                           | `git clone ...feedBack-plugin-nam-rig-builder.git nam_rig_builder`     |
+| [Audio Preview](https://github.com/saleemk/slopsmith-plugin-audio-preview)         | Quick audio previews from library cards with configurable start time, volume, and duration                                                                                                                                       | `git clone ...slopsmith-plugin-audio-preview.git audio_preview`         |
-| [Audio Preview](https://github.com/saleemk/feedBack-plugin-audio-preview)         | Quick audio previews from library cards with configurable start time, volume, and duration                                                                                                                                       | `git clone ...feedBack-plugin-audio-preview.git audio_preview`         |
+| [Song Mastery](https://github.com/jamesgaiser/slopsmith-plugin-song-mastery)       | Auto-adjusts difficulty based on your rolling note accuracy and saves the slider position per song                                                                                                                               | `git clone ...slopsmith-plugin-song-mastery.git song_mastery`           |
-| [Song Mastery](https://github.com/jamesgaiser/feedBack-plugin-song-mastery)       | Auto-adjusts difficulty based on your rolling note accuracy and saves the slider position per song                                                                                                                               | `git clone ...feedBack-plugin-song-mastery.git song_mastery`           |
+| [Mobile Note Highway](https://github.com/saleemk/slopsmith-plugin-mobile-note-highway) | Touch-optimized player with collapsible controls, highway gestures, and device-adaptive layouts for phones and tablets | `git clone ...slopsmith-plugin-mobile-note-highway.git mobile_note_highway` |
-| [Song Preview](https://github.com/DeathlySin/feedBack-plugin-song-preview)        | Quickly hear previews of songs in your library with a clean visual indicator of what's playing. Supports .sloppak and loose folders song formats, with the visual indicator matching up to whatever theme you are using!         | `git clone ...feedBack-plugin-song-preview.git song_preview`           |
-| [Mobile Note Highway](https://github.com/saleemk/feedBack-plugin-mobile-note-highway) | Touch-optimized player with collapsible controls, highway gestures, and device-adaptive layouts for phones and tablets | `git clone ...feedBack-plugin-mobile-note-highway.git mobile_note_highway` |
-| [Shuffle](https://github.com/Erikcb91/FeedBack-Shuffle-Mode) | Random playback from your library — artist & tuning filters, auto-advance with countdown popup, note_detect compatible | `git clone https://github.com/Erikcb91/FeedBack-Shuffle-Mode.git shuffle` |
 
 Install any plugin by cloning it into your `plugins/` directory and restarting:
 

lib/diagnostics_hardware.py

@@ -16,6 +16,8 @@ import platform
 import subprocess
 from pathlib import Path
 
+from env_compat import getenv_compat
+
 SCHEMA = "system.hardware.v1"
 
 
@@ -41,7 +43,7 @@ def detect_runtime() -> dict:
     nvidia-smi / psutil CPU probes.
     """
     out: dict = {"kind": "bare", "in_docker": False, "in_kubernetes": False}
-    env_runtime = os.environ.get("FEEDBACK_RUNTIME", "").strip().lower()
+    env_runtime = (getenv_compat("FEEDBACK_RUNTIME", "") or "").strip().lower()
     if env_runtime in ("electron", "docker", "bare"):
         out["kind"] = env_runtime
     if Path("/.dockerenv").exists():

lib/env_compat.py

@@ -0,0 +1,38 @@
+"""Backward-compatible environment lookup for the slopsmith -> feedBack rename.
+
+Canonical configuration variables are now ``FEEDBACK_*``. Deployments that
+predate the rename may still set the old ``SLOPSMITH_*`` names (docker-compose
+overrides, shell profiles, CI), so we honour those as a fallback. New code
+should always read the canonical ``FEEDBACK_*`` name and let this shim resolve
+the legacy alias.
+
+Flat-importable, no import-time IO or global state (constitution P-V).
+"""
+
+import os
+
+_CANON_PREFIX = "FEEDBACK_"
+_LEGACY_PREFIX = "SLOPSMITH_"
+_TRUE_VALUES = {"1", "true", "yes", "on"}
+
+
+def getenv_compat(name, default=None):
+    """``os.environ.get`` with a legacy ``SLOPSMITH_*`` fallback.
+
+    For a canonical ``FEEDBACK_<X>`` name, returns the value of ``FEEDBACK_<X>``
+    if set, else ``SLOPSMITH_<X>`` if set, else ``default``. Names that do not
+    start with ``FEEDBACK_`` behave exactly like ``os.environ.get``.
+    """
+    value = os.environ.get(name)
+    if value is not None:
+        return value
+    if name.startswith(_CANON_PREFIX):
+        legacy = os.environ.get(_LEGACY_PREFIX + name[len(_CANON_PREFIX):])
+        if legacy is not None:
+            return legacy
+    return default
+
+
+def env_flag_compat(name):
+    """Parse a conventional boolean env flag, honouring the legacy alias."""
+    return (getenv_compat(name, "") or "").strip().lower() in _TRUE_VALUES

lib/gp2midi.py

@@ -8,6 +8,8 @@ import sys
 import tempfile
 from pathlib import Path
 
+from env_compat import getenv_compat
+
 log = logging.getLogger("feedBack.lib.gp2midi")
 
 import guitarpro
@@ -156,7 +158,7 @@ def _find_soundfont() -> str | None:
       2. Bundled ``<RESOURCESPATH>/soundfonts/*.sf2`` (Electron desktop builds)
       3. Common system locations per OS.
     """
-    override = os.environ.get("FEEDBACK_SOUNDFONT")
+    override = getenv_compat("FEEDBACK_SOUNDFONT")
     if override:
         if os.path.isfile(override):
             return override

lib/tailwind_rebuild.py

@@ -24,6 +24,8 @@ import tempfile
 import threading
 from pathlib import Path
 
+from env_compat import getenv_compat
+
 log = logging.getLogger("feedBack.tailwind")
 
 # Pin matches scripts/build-tailwind.sh and the Dockerfile build stage so every
@@ -45,7 +47,7 @@ APP_DIR = Path(__file__).resolve().parent.parent
 
 
 def _user_plugins_dir() -> Path | None:
-    raw = os.environ.get("FEEDBACK_PLUGINS_DIR", "").strip()
+    raw = (getenv_compat("FEEDBACK_PLUGINS_DIR", "") or "").strip()
     if not raw:
         return None
     p = Path(raw)

plugins/__init__.py

@@ -1118,7 +1118,7 @@ def load_plugins(app: FastAPI, context: dict, progress_cb=None, route_setup_fn=N
 
     # Collect plugin directories — user plugins first so they override built-in
     plugin_dirs = []
-    user_plugins_dir = os.environ.get("FEEDBACK_PLUGINS_DIR") or os.environ.get("FEEDBACK_PLUGINS_DIR")
+    user_plugins_dir = os.environ.get("FEEDBACK_PLUGINS_DIR") or os.environ.get("SLOPSMITH_PLUGINS_DIR")
     if user_plugins_dir:
         user_path = Path(user_plugins_dir)
         if user_path.is_dir() and user_path != PLUGINS_DIR:

plugins/minigames/routes.py

@@ -336,7 +336,7 @@ def setup(app, context):
     # Duplicates are removed via a seen-set keyed on resolved paths.
     def _resolve_plugin_dirs():
         roots = []
-        env_dir = os.environ.get("FEEDBACK_PLUGINS_DIR") or os.environ.get("FEEDBACK_PLUGINS_DIR")
+        env_dir = os.environ.get("FEEDBACK_PLUGINS_DIR") or os.environ.get("SLOPSMITH_PLUGINS_DIR")
         if env_dir:
             roots.append(Path(env_dir))
         # Built-in plugins/ next to server.py (one level above this file's

server.py

@@ -15,6 +15,7 @@ from pathlib import Path
 from typing import Any, ClassVar
 
 from logging_setup import configure_logging
+from env_compat import getenv_compat
 configure_logging()
 
 log = logging.getLogger("feedBack.server")
@@ -230,7 +231,7 @@ _DEMO_BLOCKED: list[tuple[str, re.Pattern]] = [
 
 @app.middleware("http")
 async def _demo_mode_guard(request: Request, call_next):
-    if os.environ.get("FEEDBACK_DEMO_MODE") or os.environ.get("FEEDBACK_DEMO_MODE") == "1":
+    if getenv_compat("FEEDBACK_DEMO_MODE") or getenv_compat("FEEDBACK_DEMO_MODE") == "1":
         path = request.url.path
         for method, pattern in _DEMO_BLOCKED:
             if request.method == method and pattern.match(path):
@@ -275,8 +276,8 @@ SLOPPAK_CACHE_DIR = CONFIG_DIR / "sloppak_cache"
 
 
 def _env_flag(name: str) -> bool:
-    """Parse a conventional boolean env flag."""
+    """Parse a conventional boolean env flag (honours legacy SLOPSMITH_* alias)."""
-    return os.environ.get(name, "").strip().lower() in {"1", "true", "yes", "on"}
+    return (getenv_compat(name, "") or "").strip().lower() in {"1", "true", "yes", "on"}
 
 
 # Canonical Tuning-filter grouping key (feedBack#867). tuning_name collapses
@@ -3040,7 +3041,7 @@ def _make_scan_executor():
     # A malformed override falls back to the core count rather than crashing.
     try:
         max_workers = int(
-            os.environ.get("FEEDBACK_MAX_SCAN_WORKERS")
+            getenv_compat("FEEDBACK_MAX_SCAN_WORKERS")
             or os.environ.get("SCAN_MAX_WORKERS")
             or (os.cpu_count() or 1)
         )
@@ -3090,7 +3091,7 @@ def _get_progression_content() -> dict:
         with _progression_content_lock:
             if _progression_content is None:
                 import progression as progression_mod
-                root = os.environ.get("FEEDBACK_PROGRESSION_DATA") or (
+                root = getenv_compat("FEEDBACK_PROGRESSION_DATA") or (
                     _feedBack_server_root() / "data" / "progression"
                 )
                 content, warnings = progression_mod.load_content(root)
@@ -3488,7 +3489,7 @@ async def startup_events():
 
     # Load plugins asynchronously so HTTP routes and the desktop window can
     # come up immediately while heavy plugin imports/install steps continue.
-    _sync_mode = os.environ.get("FEEDBACK_SYNC_STARTUP", "").lower() in {"1", "true", "yes", "on"}
+    _sync_mode = getenv_compat("FEEDBACK_SYNC_STARTUP", "").lower() in {"1", "true", "yes", "on"}
 
     def _load_plugins_background():
         try:
@@ -3723,7 +3724,7 @@ async def startup_events():
         threading.Thread(target=_load_plugins_background, daemon=True).start()
 
     global _DEMO_JANITOR_STARTED, _DEMO_JANITOR_THREAD
-    if os.environ.get("FEEDBACK_DEMO_MODE") or os.environ.get("FEEDBACK_DEMO_MODE") == "1" and not _DEMO_JANITOR_STARTED:
+    if getenv_compat("FEEDBACK_DEMO_MODE") or getenv_compat("FEEDBACK_DEMO_MODE") == "1" and not _DEMO_JANITOR_STARTED:
         _DEMO_JANITOR_STARTED = True
         _DEMO_JANITOR_STOP.clear()
         def _janitor():
@@ -6183,7 +6184,7 @@ def _diag_plugins_roots() -> list[Path]:
     orphans in the external dir are reflected in the bundle.
     """
     roots: list[Path] = []
-    user_dir = os.environ.get("FEEDBACK_PLUGINS_DIR", "").strip()
+    user_dir = getenv_compat("FEEDBACK_PLUGINS_DIR", "").strip()
     if user_dir:
         p = Path(user_dir)
         if p.is_dir():
@@ -7683,7 +7684,7 @@ def index():
     # UI remains fully available as a fallback — opt back in with
     # FEEDBACK_UI=v2 (or =legacy), or hit the dedicated /v2 route below (which
     # serves it regardless of the env var).
-    if os.environ.get("FEEDBACK_UI") or os.environ.get("FEEDBACK_UI") in ("v2", "legacy"):
+    if getenv_compat("FEEDBACK_UI") or getenv_compat("FEEDBACK_UI") in ("v2", "legacy"):
         return FileResponse(str(STATIC_DIR / "index.html"))
     return FileResponse(str(STATIC_DIR / "v3" / "index.html"))
 

static/app.js

@@ -3310,7 +3310,9 @@ function setupAppUpdates() {
     // iframes, privacy modes, etc.); fall back to the default channel so the
     // panel still renders rather than aborting wiring entirely.
     let storedRaw = null;
-    try { storedRaw = localStorage.getItem('feedBack-update-channel'); } catch (_) { /* fall through */ }
+    // Read the canonical key, falling back to the pre-rename
+    // 'slopsmith-update-channel' so an existing channel preference survives.
+    try { storedRaw = localStorage.getItem('feedBack-update-channel') || localStorage.getItem('slopsmith-update-channel'); } catch (_) { /* fall through */ }
     const stored = APP_UPDATE_CHANNELS.includes(storedRaw) ? storedRaw : 'stable';
     channelSelect.value = stored;
 
@@ -3395,7 +3397,7 @@ function setupAppUpdates() {
         channelSelect.addEventListener('change', async () => {
             const val = channelSelect.value;
             if (!APP_UPDATE_CHANNELS.includes(val)) return;
-            try { localStorage.setItem('feedBack-update-channel', val); } catch (_) {}
+            try { localStorage.setItem('feedBack-update-channel', val); localStorage.removeItem('slopsmith-update-channel'); } catch (_) {}
             try {
                 // Await setChannel so the status line reflects what actually
                 // happened — rendering "Channel set" unconditionally would

tests/test_env_compat.py

@@ -0,0 +1,50 @@
+"""Coverage for the slopsmith -> feedBack env backward-compat shim."""
+
+from env_compat import getenv_compat, env_flag_compat
+
+
+def test_canonical_wins_over_legacy(monkeypatch):
+    monkeypatch.setenv("FEEDBACK_UI", "v3")
+    monkeypatch.setenv("SLOPSMITH_UI", "v2")
+    assert getenv_compat("FEEDBACK_UI") == "v3"
+
+
+def test_legacy_fallback_when_canonical_unset(monkeypatch):
+    monkeypatch.delenv("FEEDBACK_UI", raising=False)
+    monkeypatch.setenv("SLOPSMITH_UI", "v2")
+    assert getenv_compat("FEEDBACK_UI") == "v2"
+
+
+def test_default_when_neither_set(monkeypatch):
+    monkeypatch.delenv("FEEDBACK_UI", raising=False)
+    monkeypatch.delenv("SLOPSMITH_UI", raising=False)
+    assert getenv_compat("FEEDBACK_UI", "default") == "default"
+    assert getenv_compat("FEEDBACK_UI") is None
+
+
+def test_non_feedback_names_have_no_fallback(monkeypatch):
+    monkeypatch.delenv("CONFIG_DIR", raising=False)
+    monkeypatch.setenv("SLOPSMITH_CONFIG_DIR", "/tmp/x")
+    # A non-FEEDBACK_ name must behave like os.environ.get (no aliasing).
+    assert getenv_compat("CONFIG_DIR") is None
+
+
+def test_empty_canonical_is_respected_not_overridden(monkeypatch):
+    # An explicitly-empty canonical value is still "set" and wins.
+    monkeypatch.setenv("FEEDBACK_UI", "")
+    monkeypatch.setenv("SLOPSMITH_UI", "v2")
+    assert getenv_compat("FEEDBACK_UI") == ""
+
+
+def test_flag_parses_true_values(monkeypatch):
+    for raw in ("1", "true", "YES", " On "):
+        monkeypatch.setenv("FEEDBACK_SYNC_STARTUP", raw)
+        assert env_flag_compat("FEEDBACK_SYNC_STARTUP") is True
+
+
+def test_flag_false_and_legacy(monkeypatch):
+    monkeypatch.delenv("FEEDBACK_SYNC_STARTUP", raising=False)
+    monkeypatch.setenv("SLOPSMITH_SYNC_STARTUP", "1")
+    assert env_flag_compat("FEEDBACK_SYNC_STARTUP") is True
+    monkeypatch.setenv("FEEDBACK_SYNC_STARTUP", "0")
+    assert env_flag_compat("FEEDBACK_SYNC_STARTUP") is False