sahil87 · sahil-noon · Jun 13, 2026 · Jun 13, 2026 · Jun 13, 2026 · Jun 13, 2026
diff --git a/docs/memory/cli/index.md b/docs/memory/cli/index.md
@@ -10,5 +10,5 @@ description: "CLI source structure (cmd/idea + internal/idea + version wiring),
 | [edit](edit.md) | `idea edit` two-form contract: inline replacement (two-arg form) vs. $EDITOR round-trip (`edit <query>`) — editor resolution chain, temp-file mechanics, edge/exit semantics, and the fake-editor test seam | 2026-06-12 |
 | [list](list.md) | `idea list`/`ls` rendering contract: TTY-aware rune-safe text truncation, the `--full` flag, the optional `[id...]` positional filter, ANSI color (NO_COLOR-gated), and the pipe contract that keeps piped output canonical | 2026-06-13 |
 | [prune](prune.md) | Bulk-remove subcommand (`idea prune`): the TTY × `--force` decision matrix (pipe dry-run vs. interactive `[y/N]` confirm), the leading stderr count header, TTY-aware truncation/color/`--full` listing, stdout/stderr channel split, exit codes, the deliberate non-archival design, and the `removeIdeaAt` seam shared with `Rm` | 2026-06-13 |
-| [structure](structure.md) | Source tree layout (cmd/idea + internal/idea), root command factory, command aliases vs. the bare-text shorthand, backlog line lifecycle (lenient read / canonical write incl. the escaped-text convention for multiline ideas and the explicit `idea fmt` canonicalizer with bare-checkbox adoption), the TTY/width/color/truncation seam (internal/idea/term.go) + shared printIdeaLines render path, the golang.org/x/term direct dependency, help-dump contract, and version stamping | 2026-06-13 |
+| [structure](structure.md) | Source tree layout (cmd/idea + internal/idea), root command factory, backlog path resolution precedence (--system / --main / --file, the XDG system backlog ($XDG_CONFIG_HOME/idea/backlog.md, else ~/.config/idea/backlog.md), and the out-of-git graceful fallback), command aliases vs. the bare-text shorthand, backlog line lifecycle (lenient read / canonical write incl. the escaped-text convention for multiline ideas and the explicit `idea fmt` canonicalizer with bare-checkbox adoption), the TTY/width/color/truncation seam (internal/idea/term.go) + shared printIdeaLines render path, the golang.org/x/term direct dependency, help-dump contract, and version stamping | 2026-06-13 |
 | [update](update.md) | Self-update subcommand (`idea update`): Homebrew-backed upgrade flow, non-brew install fallback hint, and the `--skip-brew-update` flag | 2026-06-10 |
diff --git a/docs/memory/cli/structure.md b/docs/memory/cli/structure.md
@@ -1,5 +1,5 @@
 ---
-description: "Source tree layout (cmd/idea + internal/idea), root command factory, command aliases vs. the bare-text shorthand, backlog line lifecycle (lenient read / canonical write incl. the escaped-text convention for multiline ideas and the explicit `idea fmt` canonicalizer with bare-checkbox adoption), the TTY/width/color/truncation seam (internal/idea/term.go) + shared printIdeaLines render path, the golang.org/x/term direct dependency, help-dump contract, and version stamping"
+description: "Source tree layout (cmd/idea + internal/idea), root command factory, backlog path resolution precedence (--system / --main / --file, the XDG system backlog ($XDG_CONFIG_HOME/idea/backlog.md, else ~/.config/idea/backlog.md), and the out-of-git graceful fallback), command aliases vs. the bare-text shorthand, backlog line lifecycle (lenient read / canonical write incl. the escaped-text convention for multiline ideas and the explicit `idea fmt` canonicalizer with bare-checkbox adoption), the TTY/width/color/truncation seam (internal/idea/term.go) + shared printIdeaLines render path, the golang.org/x/term direct dependency, help-dump contract, and version stamping"
 ---
 
 # CLI Source Structure
@@ -60,11 +60,55 @@ Rule of thumb:
 
 Two principles in `fab/project/constitution.md` constrain code placement inside this layout:
 
-- **Principle III (Cobra-Idiomatic CLI Surface)** — subcommands are `*cobra.Command` factory functions in `cmd/idea/`; root command exposes the bare-text shorthand (`idea <text>` → `idea add <text>`); persistent flags (`--file`, `--main`) are defined on root.
-- **Principle IV (Logic Lives in `internal/idea`)** — parsing, formatting, ID generation, file I/O, and worktree resolution live in `internal/idea`. `cmd/` files contain only flag wiring, argument validation, and output formatting.
+- **Principle III (Cobra-Idiomatic CLI Surface)** — subcommands are `*cobra.Command` factory functions in `cmd/idea/`; root command exposes the bare-text shorthand (`idea <text>` → `idea add <text>`); persistent flags (`--file`, `--main`, `--system`) are defined on root.
+- **Principle IV (Logic Lives in `internal/idea`)** — parsing, formatting, ID generation, file I/O, worktree resolution, and backlog path resolution live in `internal/idea`. `cmd/` files contain only flag wiring, argument validation, and output formatting. The full path-resolution precedence is owned by `idea.ResolveBacklogPath` (see *Backlog path resolution* below); `resolveFile()` in `cmd/idea/resolve.go` is a one-line forwarder of the three persistent-flag values, holding no precedence logic.
 
 The split forces a testable seam — `internal/idea` is unit-tested directly (table-driven, real temp dirs, no mocks) without spawning subprocesses. `cmd/idea/main_test.go` covers the end-to-end CLI by building the binary under test.
 
+## Backlog path resolution
+
+Which backlog file a command operates on is decided by `idea.ResolveBacklogPath(systemFlag, mainFlag bool, fileFlag string) (string, error)` in `internal/idea/idea.go`. This is the sole owner of the precedence (Constitution IV); `cmd/idea/resolve.go`'s `resolveFile()` only forwards the three persistent-flag values into it. The out-of-git fallback and the system backlog were added by `260613-2b3m-system-level-backlog`, which made `idea` usable outside any git repository — previously every command shelled out to `git rev-parse` and **failed hard** ("not in a git repository") in any non-repo directory, with `--file`/`IDEAS_FILE` unable to rescue it because their values were still joined to the failed git root.
+
+### Three persistent root selectors
+
+Defined on root in `newRootCmd()` (`cmd/idea/main.go`):
+
+| Flag | Var | Effect |
+|------|-----|--------|
+| `--file <path>` / `IDEAS_FILE` env | `fileFlag` | Override the backlog file path; rooted at the git root inside a repo, else at `~/.config/idea` (an absolute value is honored verbatim). |
+| `--main` | `mainFlag` | Operate on the **main worktree's** backlog. Git-only (errors outside a repo) — unchanged by 2b3m. |
+| `--system` | `systemFlag` | Operate on the **system backlog**, from anywhere including inside a repo; skips git entirely. Peer of `--main`, added by 2b3m. |
+
+### Precedence (first match wins)
+
+`ResolveBacklogPath` resolves in this order:
+
+1. **`--system`** → the system backlog (`SystemBacklogPath()`); git is skipped entirely.
+2. **`--main`** → the main worktree root (`MainRepoRoot()`), then `--file`/`IDEAS_FILE` rooting applied via `ResolveFilePath`. Git-only — errors with "not in a git repository" outside a repo (unchanged).
+3. **Inside a git repo, no `--system`/`--main`** → `WorktreeRoot()` succeeds → `ResolveFilePath(worktreeRoot, fileFlag)`: a `--file`/`IDEAS_FILE` override joined to the worktree root, else the **unchanged default** `{worktree-root}/fab/backlog.md`.
+4. **Outside any git repo, no `--system`/`--main`** → `WorktreeRoot()` errors → the **graceful fallback**: a relative `--file`/`IDEAS_FILE` value is joined to `~/.config/idea`, an absolute one is honored verbatim, and with no override the path is the system backlog (`{config-dir}/idea/backlog.md`). Commands no longer fail outside a repo.
+
+**`--system` + `--main` is a hard conflict.** Both select a root; passing both returns `--system and --main are mutually exclusive; pass only one` (non-zero exit via the existing top-level `ERROR:` handler) and resolves no path. The check is the first line of `ResolveBacklogPath`, colocated with the precedence it guards rather than in a separate cobra `PreRunE`.
+
+### System backlog location (XDG)
+
+`SystemBacklogPath() (string, error)` returns `{config-dir}/idea/backlog.md`, where `config-dir` comes from Go stdlib `os.UserConfigDir()` — `$XDG_CONFIG_HOME` when set, else `~/.config` on Unix. So:
+
+- `XDG_CONFIG_HOME=/custom/cfg` → `/custom/cfg/idea/backlog.md`
+- unset, `HOME=/home/u` → `/home/u/.config/idea/backlog.md`
+
+This mirrors `hop`'s `~/.config/hop/hop.yaml` convention and stays stdlib-only — **no new dependency** (Dependency Discipline). `os.UserConfigDir` is the only XDG-resolution path; both `SystemBacklogPath` and the out-of-git override-rooting branch use it.
+
+### On-demand config-dir creation
+
+The system config dir (`~/.config/idea/`) is created lazily on the **first mutating write**, not on read. The `os.MkdirAll(filepath.Dir(path), 0755)` lives at the single SaveFile serialization seam — `atomicWriteFile` — so every SaveFile-based mutation (`done`/`reopen`/`edit`/`rm`/`prune --force`/`fmt`) creates a missing dir before writing; `Add` already MkdirAll's its own path independently. Read-only commands (`list`/`show`) on a non-existent system backlog take the existing "no ideas file yet" path — they neither create the dir nor error.
+
+### Format is path-independent
+
+Only path resolution changed. The backlog file format, ID rules, escaping, canonical write, and all CRUD/`fmt`/`list`/`show`/JSON semantics are byte-for-byte identical regardless of which path resolved (Constitution I) — the system backlog is the same canonical Markdown checklist at a different location. The behavior contract for external consumers is in `../../specs/overview.md` ("Worktree Behavior" + resolution precedence).
+
+**Constitution II scope.** Principle II ("worktree-aware by default, all resolution via `git rev-parse`") still governs the in-git case — git resolution remains the default and the only path used when a repo is present and no override is given. 2b3m added a *sanctioned* non-git path (the system backlog) without amending Principle II; the escape hatch is documented in the spec/overview only, a deliberate non-blocking judgment call left at intake.
+
 ## Backlog line lifecycle (lenient read, canonical write)
 
 `internal/idea/idea.go` owns the parse/format/save contract for backlog lines. The governing principle is **lenient on read, canonical on write** (be liberal in what you accept, strict in what you emit). This shape was established by `260610-wtmn-resilient-backlog-parser`, which fixed silent-failure parsing of dateless backlogs (e.g. shll.ai's `- [ ] [id] text` form).
@@ -202,7 +246,7 @@ This is the single source for the shll.ai command-reference: the `help-dump` sub
 
 ## Root command factory
 
-`cmd/idea/main.go` builds the root command through a `newRootCmd() *cobra.Command` factory rather than inline inside `main()`. The factory constructs root (with `Version: version`, the bare-text shorthand `RunE`, and the `--file`/`--main` persistent flags) and registers every subcommand:
+`cmd/idea/main.go` builds the root command through a `newRootCmd() *cobra.Command` factory rather than inline inside `main()`. The factory constructs root (with `Version: version`, the bare-text shorthand `RunE`, and the `--file`/`--main`/`--system` persistent flags — see *Backlog path resolution* above for what each selects) and registers every subcommand:
 
 ```go
 root.AddCommand(
@@ -217,7 +261,7 @@ The factory exists so the live cobra tree can be constructed in two places off t
 
 ## Command aliases and the bare-text shorthand
 
-`list` is the only subcommand with an alias: `Aliases: []string{"ls"}` in the `listCmd()` command literal (`cmd/idea/list.go`), added by `260610-04rt-add-ls-alias`. `idea ls` is identical to `idea list` in every respect — same flags (`--all/-a`, `--done`, `--json`, `--sort`, `--reverse`), same inherited persistent flags (`--file`, `--main`), same output. The alias is pure routing; the `list` command's behavior and JSON output are unchanged.
+`list` is the only subcommand with an alias: `Aliases: []string{"ls"}` in the `listCmd()` command literal (`cmd/idea/list.go`), added by `260610-04rt-add-ls-alias`. `idea ls` is identical to `idea list` in every respect — same flags (`--all/-a`, `--done`, `--json`, `--sort`, `--reverse`), same inherited persistent flags (`--file`, `--main`, `--system`), same output. The alias is pure routing; the `list` command's behavior and JSON output are unchanged.
 
 **Routing rule (load-bearing).** Cobra resolves subcommand names **and aliases** before the root `RunE` bare-text fallback fires. Two consequences:
 

diff --git a/docs/specs/overview.md b/docs/specs/overview.md
@@ -24,7 +24,22 @@ The manual installer builds the binary via `./scripts/build.sh` and copies it to
 
 By default, `idea` operates on the **current worktree's** `fab/backlog.md` (resolved via `git rev-parse --show-toplevel`). Pass `--main` to target the main worktree's backlog instead; internally, `idea` resolves the main worktree root by running `git rev-parse --path-format=absolute --git-common-dir` and taking its parent directory. In the main worktree, both behave identically. This ensures that users in a linked worktree get predictable local behavior unless they explicitly opt into the shared backlog.
 
-The backlog file path can also be overridden globally by `--file <path>` (relative to the resolved git root) or by setting the `IDEAS_FILE` environment variable.
+The backlog file path can also be overridden globally by `--file <path>` or by setting the `IDEAS_FILE` environment variable.
+
+### System backlog and out-of-git operation
+
+`idea` also works **outside any git repository** and offers a **system-level backlog** for cross-repo idea capture. The system backlog lives at `$XDG_CONFIG_HOME/idea/backlog.md` when `XDG_CONFIG_HOME` is set, and `~/.config/idea/backlog.md` otherwise (resolved via Go's `os.UserConfigDir`). Its parent directory is created on demand on the first mutating write. The file format and all command semantics are identical to a repo backlog — only the path differs.
+
+The backlog path is resolved by this precedence (first match wins). Note that `--main` and `--file`/`IDEAS_FILE` are **not** independent alternatives: `--main` selects which *root* is used, and `--file`/`IDEAS_FILE` (when set) are applied *within* that selected root.
+
+1. **`--system`** — the system backlog, skipping git entirely (reachable from inside a repo too).
+2. **`--main`** — root = the main worktree root. Git-only: it still errors with `not in a git repository` outside a repo. A `--file`/`IDEAS_FILE` value, if set, is rooted here.
+3. **In a git repo (no `--main`)** — root = the current worktree root. A `--file`/`IDEAS_FILE` value, if set, is rooted here; otherwise `{worktree-root}/fab/backlog.md` (the default).
+4. **Outside a git repo (no `--main`)** — root = the system config dir (`$XDG_CONFIG_HOME/idea/`, else `~/.config/idea/`). A `--file`/`IDEAS_FILE` value, if set, is rooted here; otherwise the system backlog (the graceful fallback; commands no longer fail with `not in a git repository`).
+
+In all rooted cases an absolute `--file`/`IDEAS_FILE` value is used verbatim.
+
+`--system` and `--main` are mutually exclusive — passing both is a user error and exits non-zero.
 
 ## Commands
 

diff --git a/fab/changes/260613-2b3m-system-level-backlog/.history.jsonl b/fab/changes/260613-2b3m-system-level-backlog/.history.jsonl
@@ -0,0 +1,14 @@
+{"action":"enter","driver":"fab-new","event":"stage-transition","stage":"intake","ts":"2026-06-13T07:43:29Z"}
+{"args":"Allow idea to work even out of git folders. Use a system level backlog.md to track ideas at a system level","cmd":"fab-new","event":"command","ts":"2026-06-13T07:43:29Z"}
+{"delta":"+1.6","event":"confidence","score":1.6,"trigger":"calc-score","ts":"2026-06-13T07:44:30Z"}
+{"delta":"+0.0","event":"confidence","score":1.6,"trigger":"calc-score","ts":"2026-06-13T07:44:34Z"}
+{"delta":"+1.5","event":"confidence","score":3.1,"trigger":"calc-score","ts":"2026-06-13T07:45:15Z"}
+{"delta":"+0.0","event":"confidence","score":3.1,"trigger":"calc-score","ts":"2026-06-13T07:45:20Z"}
+{"cmd":"fab-fff","event":"command","ts":"2026-06-13T07:46:40Z"}
+{"action":"enter","driver":"fab-fff","event":"stage-transition","stage":"apply","ts":"2026-06-13T07:46:44Z"}
+{"action":"enter","driver":"fab-fff","event":"stage-transition","stage":"review","ts":"2026-06-13T07:54:47Z"}
+{"action":"enter","driver":"fab-fff","event":"stage-transition","stage":"hydrate","ts":"2026-06-13T07:59:06Z"}
+{"event":"review","result":"passed","ts":"2026-06-13T07:59:06Z"}
+{"action":"enter","driver":"fab-fff","event":"stage-transition","stage":"ship","ts":"2026-06-13T08:01:31Z"}
+{"action":"enter","driver":"git-pr","event":"stage-transition","stage":"review-pr","ts":"2026-06-13T08:02:57Z"}
+{"event":"review","result":"passed","ts":"2026-06-13T08:13:06Z"}
diff --git a/fab/changes/260613-2b3m-system-level-backlog/.status.yaml b/fab/changes/260613-2b3m-system-level-backlog/.status.yaml
@@ -0,0 +1,51 @@
+id: 2b3m
+name: 260613-2b3m-system-level-backlog
+created: 2026-06-13T07:43:29Z
+created_by: sahil-noon
+change_type: feat
+issues: []
+progress:
+    intake: done
+    apply: done
+    review: done
+    hydrate: done
+    ship: done
+    review-pr: done
+plan:
+    generated: true
+    task_count: 9
+    acceptance_count: 13
+    acceptance_completed: 0
+confidence:
+    certain: 6
+    confident: 3
+    tentative: 1
+    unresolved: 0
+    score: 3.1
+    fuzzy: true
+    dimensions:
+        signal: 74.8
+        reversibility: 76.0
+        competence: 80.5
+        disambiguation: 80.0
+stage_metrics:
+    intake: {started_at: "2026-06-13T07:43:29Z", driver: fab-new, iterations: 1, completed_at: "2026-06-13T07:46:44Z"}
+    apply: {started_at: "2026-06-13T07:46:44Z", driver: fab-fff, iterations: 1, completed_at: "2026-06-13T07:54:47Z"}
+    review: {started_at: "2026-06-13T07:54:47Z", driver: fab-fff, iterations: 1, completed_at: "2026-06-13T07:59:06Z"}
+    hydrate: {started_at: "2026-06-13T07:59:06Z", driver: fab-fff, iterations: 1, completed_at: "2026-06-13T08:01:31Z"}
+    ship: {started_at: "2026-06-13T08:01:31Z", driver: fab-fff, iterations: 1, completed_at: "2026-06-13T08:02:57Z"}
+    review-pr: {started_at: "2026-06-13T08:02:57Z", driver: git-pr, iterations: 1, completed_at: "2026-06-13T08:13:06Z"}
+prs:
+    - https://github.com/sahil87/idea/pull/19
+true_impact:
+    added: 0
+    deleted: 0
+    net: 0
+    excluding:
+        added: 0
+        deleted: 0
+        net: 0
+    computed_at: "2026-06-13T08:01:31Z"
+    computed_at_stage: hydrate
+# true_impact: lazily created on first apply-finish (no placeholder here).
+last_updated: 2026-06-13T08:13:06Z