diff --git a/PROJECTS.md b/PROJECTS.md
index 0f569ca..51e38dd 100644
--- a/PROJECTS.md
+++ b/PROJECTS.md
@@ -13,6 +13,7 @@
 - [ ] Local-first app development
 
 ## Interactive Learning and Education
+- [ ] Git worktrees, how do use please
 - [ ] How to structure a co-op profit sharing worker owned business
 - [ ] Hands-on: Markov Chains
 - [ ] Hands-on: Vector Databases
diff --git a/nbd/.claude/skills/work/SKILL.md b/nbd/.claude/skills/work/SKILL.md
index 3be2355..1ee2e5c 100644
--- a/nbd/.claude/skills/work/SKILL.md
+++ b/nbd/.claude/skills/work/SKILL.md
@@ -3,7 +3,8 @@ name: work
 description: work on the highest priority thing
 ---
 
-* Use nbd to choose the highest priority issue with no outstanding dependencies.
+* If a ticket ID or description of a ticket is provided, look for that ticket.
+* If no ticket/description is provided, use nbd next to choose the ticket to work on.
 * Thoroughly investigate the relevant parts of the codebase to ensure you understand the problem and how to implement the solution as describe in the ticket.
 * Implement the plan in the selected ticket.
 * Once complete validate changes with cargo fmt, cargo check, cargo clippy, and cargo test.
diff --git a/nbd/.nbd/tickets/4036aa.md b/nbd/.nbd/tickets/4036aa.md
new file mode 100644
index 0000000..b4c9844
--- /dev/null
+++ b/nbd/.nbd/tickets/4036aa.md
@@ -0,0 +1,97 @@
++++
+title = "Print tickets in markdown format instead of key-value table"
+priority = 5
+status = "todo"
+ticket_type = "feature"
+dependencies = []
++++
+## Goal
+
+When a ticket is printed to stdout (e.g. by `nbd read`, `nbd create`, `nbd archive`, `nbd next`, `nbd update` without `--json`), it should be rendered as markdown with TOML frontmatter — the same format used by `--ftype md` files on disk — rather than the current key-value table.
+
+`--json` output is unaffected.
+
+## Current output (`nbd read <id>`)
+
+```
+ID:           a3f9c2
+Title:        Fix login bug
+Body:         Users cannot log in with email +
+Priority:     8
+Status:       in_progress
+Type:         bug
+Dependencies: b7d41e, c9e823
+```
+
+## Target output
+
+```
++++
+title = "Fix login bug"
+priority = 8
+status = "in_progress"
+ticket_type = "bug"
+dependencies = ["b7d41e", "c9e823"]
++++
+Users cannot log in with email +
+```
+
+The `id` field is not in the frontmatter on disk (filename is the source of truth), but for display purposes it should appear as a comment or additional line. Recommended approach: add `id = "a3f9c2"` as the **first key** in the frontmatter so it's immediately visible:
+
+```
++++
+id = "a3f9c2"
+title = "Fix login bug"
+priority = 8
+status = "in_progress"
+ticket_type = "bug"
+dependencies = ["b7d41e", "c9e823"]
++++
+Users cannot log in with email +
+```
+
+## Files to change
+
+### `src/display.rs`
+
+Replace `format_ticket` with a markdown-rendering implementation. The simplest approach reuses `serialize_markdown` from `src/store.rs`, adding `id` to the frontmatter output.
+
+Option A (preferred): expose `serialize_markdown` from `store.rs` as `pub(crate)` and call it from `display.rs`, prepending the `id` line to the TOML frontmatter block.
+
+Option B: duplicate the logic in `display.rs` as a display-specific formatter that includes `id`.
+
+The `print_ticket` function should call the new formatter.
+
+### `src/tests.rs`
+
+Update any unit tests for `format_ticket` that check the old key-value table format. They should now expect TOML frontmatter.
+
+### `tests/integration.rs`
+
+Update any integration tests that check the plain-text output of `nbd read`, `nbd create`, etc.
+
+## Commands affected
+
+Any command that calls `display::print_ticket`:
+- `nbd create` (non-JSON path)
+- `nbd read` (non-JSON path)
+- `nbd archive` (non-JSON path)
+- `nbd next` (non-JSON path, single ticket)
+- `nbd update` currently calls `print_diff`, so it is **not** affected
+
+## Validation
+
+```sh
+cargo fmt && cargo check && cargo clippy && cargo test
+cargo run -- create --title "Test ticket" --body "Some body text" --priority 7 --type bug
+# Output should be:
+# +++
+# id = "<id>"
+# title = "Test ticket"
+# priority = 7
+# status = "todo"
+# ticket_type = "bug"
+# dependencies = []
+# +++
+# Some body text
+```
\ No newline at end of file
diff --git a/nbd/.nbd/tickets/8b4041.md b/nbd/.nbd/tickets/8b4041.md
new file mode 100644
index 0000000..5c52f97
--- /dev/null
+++ b/nbd/.nbd/tickets/8b4041.md
@@ -0,0 +1,58 @@
++++
+title = "Change graph cycle marker from [cycle] to *"
+priority = 3
+status = "todo"
+ticket_type = "task"
+dependencies = []
++++
+## Goal
+
+When `nbd graph` renders a node that has already been visited (a node appearing in multiple branches of the tree), it currently labels the repeat occurrence as `[cycle]`. This label is misleading — the node isn't truly in a cycle, it's simply appearing twice in the tree because it's depended on from multiple places. Change the marker to `*` to indicate "this ticket appears elsewhere in the tree".
+
+## Current output
+
+```
+a3f9c2  [todo]  Fix login bug
+├── b7d41e  [in_progress]  Add rate limiting
+│   └── c9e823  [todo]  Write tests
+└── c9e823  [cycle]
+```
+
+## Target output
+
+```
+a3f9c2  [todo]  Fix login bug
+├── b7d41e  [in_progress]  Add rate limiting
+│   └── c9e823  [todo]  Write tests
+└── c9e823  *
+```
+
+## Files to change
+
+### `src/display.rs`
+
+In the `render_node` function (around line 409), change the cycle rendering line from:
+
+```rust
+append_line(out, &format!("{prefix}{connector}{id}  [cycle]"));
+```
+
+to:
+
+```rust
+append_line(out, &format!("{prefix}{connector}{id}  *"));
+```
+
+### README.md
+
+Update the `nbd graph` section example to replace `[cycle]` with `*` in the documentation.
+
+## Validation
+
+```sh
+cargo fmt && cargo check && cargo clippy && cargo test
+# Create two tickets that share a dependency, then graph them
+cargo run -- graph
+```
+
+Any test that checks for `[cycle]` in graph output needs updating to expect `*` instead.
\ No newline at end of file
diff --git a/nbd/.nbd/tickets/9344a5.md b/nbd/.nbd/tickets/9344a5.md
new file mode 100644
index 0000000..b1108e8
--- /dev/null
+++ b/nbd/.nbd/tickets/9344a5.md
@@ -0,0 +1,51 @@
++++
+title = "Update claude-md snippet to show --json on all commands"
+priority = 4
+status = "todo"
+ticket_type = "task"
+dependencies = []
++++
+## Goal
+
+The `nbd claude-md` command emits `src/claude_md_snippet.md` verbatim. The current snippet shows core commands without `--json`, contradicting the guideline at the bottom that says to always pass it.
+
+## What to change
+
+In `src/claude_md_snippet.md`, update the **Core commands** section so every example includes `--json`:
+
+```sh
+# Create a new ticket (use --ftype md for a human-readable body)
+nbd create --title "Add OAuth login" --type feature --priority 7 --ftype md --json
+
+# List all open tickets (sorted by priority)
+nbd list --json
+
+# Read a specific ticket
+nbd read <id> --json
+
+# Update a ticket
+nbd update <id> --status in_progress --json
+nbd update <id> --status done --json
+```
+
+Also update the **Workflow** numbered list to use `--json` in every command:
+
+```
+1. **Before starting** — create a ticket: `nbd create --title "..." --ftype md --json`
+2. **When starting** — mark it in progress: `nbd update <id> --status in_progress --json`
+3. **When done** — mark it complete: `nbd update <id> --status done --json`
+```
+
+The `nbd ready` and `nbd next` sections should also include `--json`.
+
+## Files
+
+- `src/claude_md_snippet.md` — the only file that needs changing
+
+## Validation
+
+```sh
+cargo run -- claude-md | grep -c '\-\-json'
+```
+
+The count should go up after the change. All existing tests should still pass.
\ No newline at end of file
diff --git a/nbd/.nbd/tickets/feb901.md b/nbd/.nbd/tickets/feb901.md
new file mode 100644
index 0000000..efb3619
--- /dev/null
+++ b/nbd/.nbd/tickets/feb901.md
@@ -0,0 +1,88 @@
++++
+title = "Split archive/closed: archive=done, closed=cancelled"
+priority = 6
+status = "todo"
+ticket_type = "bug"
+dependencies = []
++++
+## Problem
+
+Currently `nbd archive` sets a ticket's status to `closed`. This conflates two distinct intents:
+
+- A ticket that **was completed** and is being retired from the active list
+- A ticket that **will not be completed** (e.g. cancelled, superseded, won't-fix)
+
+## Desired semantics
+
+| Status | Meaning | Resolved (unblocks deps)? | Visible in `nbd list` by default? |
+|---|---|---|---|
+| `archived` | Completed and soft-deleted from view | Yes | No |
+| `closed` | Won't be completed (cancelled/won't-fix) | Yes (avoids deadlock) | No |
+
+Both statuses resolve dependencies, so a ticket depending on an `archived` or `closed` ticket becomes unblocked. This matches current behaviour for `closed`.
+
+## Changes required
+
+### `src/ticket.rs`
+
+Add `Archived` variant to `Status`:
+
+```rust
+pub enum Status {
+    #[default]
+    Todo,
+    InProgress,
+    Done,
+    Closed,
+    Archived,  // new
+}
+```
+
+Serialises as `"archived"`.
+
+### `src/main.rs`
+
+- `parse_status`: add `"archived" => Ok(Status::Archived)` arm and update error message
+- `cmd_archive`: change `ticket.status = Status::Closed` → `ticket.status = Status::Archived`
+- `cmd_list`: exclude `Status::Archived` alongside `Done` and `Closed` in the default filter path
+- `cmd_ready` / `cmd_next`: treat `Status::Archived` as resolved (count it in `done_ids`)
+- Update the `Archive` command docstring to say it sets status to `archived` not `closed`
+
+### `src/display.rs`
+
+- `status_str`: add `Status::Archived => "archived"` arm
+
+### `src/graph.rs`
+
+- `status_str` (internal helper): add `Status::Archived => "archived"` arm
+
+### README.md
+
+- Update the Status table to show `archived` as a valid status
+- Update `nbd archive` description to say it sets status to `archived`
+- Update the note about `archived` vs `closed` semantics
+
+### CLAUDE.md
+
+- Update CLI Interface block to include `archived` in valid status values
+- Update `nbd archive` description
+
+### `src/tests.rs` / `tests/integration.rs`
+
+- Update any test that checks `status == "closed"` after `nbd archive` → expect `"archived"` instead
+- Add test: `nbd archive <id>` produces `"archived"` status
+- Add test: a ticket with `status=closed` (manually set) is also excluded from list by default and treated as resolved
+
+## Migration concern
+
+Existing tickets on disk that have `status: "closed"` set by previous `nbd archive` calls will retain `closed` status. This is acceptable — `closed` remains a valid status. Users who want to distinguish can `nbd update <id> --status archived` on historical tickets, or run `nbd migrate` once the schema is updated.
+
+## Validation
+
+```sh
+cargo fmt && cargo check && cargo clippy && cargo test
+cargo run -- create --title "Test archive" --json | jq -r '.id' | xargs -I{} cargo run -- archive {} --json
+# → status should be "archived"
+cargo run -- create --title "Cancelled ticket" --json | jq -r '.id' | xargs -I{} cargo run -- update {} --status closed --json
+# → status should be "closed"
+```
\ No newline at end of file
diff --git a/nbd/TODO.md b/nbd/TODO.md
index baa42f5..86970a8 100644
--- a/nbd/TODO.md
+++ b/nbd/TODO.md
@@ -2,6 +2,10 @@
 
 ---
 
+`nbd claude-md` should advise using `--json` for all commands.
+
+---
+
 Add a new `backlog` state to tickets.
 The goal of this is tickets which are created but should not be worked on yet.
 Tickets with this status do not show up by default in `nbd list`, `nbd ready`, and `nbd next`.
diff --git a/nbd/flake.lock b/nbd/flake.lock
new file mode 100644
index 0000000..244e7d5
--- /dev/null
+++ b/nbd/flake.lock
@@ -0,0 +1,48 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1771369470,
+        "narHash": "sha256-0NBlEBKkN3lufyvFegY4TYv5mCNHbi5OmBDrzihbBMQ=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "0182a361324364ae3f436a63005877674cf45efb",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs",
+        "rust-overlay": "rust-overlay"
+      }
+    },
+    "rust-overlay": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1771816254,
+        "narHash": "sha256-vkp3iTF6QmHMvL+34DI93IiMPjS2lqcMlA1fl7nXVsQ=",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "rev": "085bdbf5dde5477538e4c87d1684b6c6df56c0ad",
+        "type": "github"
+      },
+      "original": {
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}