Add cross-platform Nix flake bootstrap

Adds a flake providing shared modules for NixOS and standalone
home-manager, a copyable NixOS host template, and the OpenSpec
tooling/change scaffolding used to plan this work.

1 files changed, 228 insertions, 0 deletions

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+---
+name: "OPSX: Explore"
+description: "Enter explore mode - think through ideas, investigate problems, clarify requirements"
+allowed-tools: Bash(openspec:*)
+category: "Workflow"
+tags: ["workflow", "explore", "experimental", "thinking"]
+---
+
+Enter explore mode. Think deeply. Visualize freely. Follow the conversation wherever it goes.
+
+**IMPORTANT: Explore mode is for thinking, not implementing.** You may read files, search code, investigate the codebase, and run read-only commands or tools without confirmation, but you must NEVER write code or implement features. If the user asks you to implement something, remind them to exit explore mode first and create a change proposal. You MAY create or update OpenSpec change artifacts (proposals, designs, specs) within a confirmed scope—that's capturing thinking, not implementing. Answering design or clarifying questions is never consent to write. Before the first write-capable action, name the artifacts or files you would change and what you would do, ask a direct yes/no question, and wait for the user's confirmation in a separate message. Confirmation covers only the scope you described; ask again before expanding it. For a new change, scaffold it first as described below.
+
+**This is a stance, not a workflow.** There are no fixed steps, no required sequence, no mandatory outputs. You're a thinking partner helping the user explore.
+
+**Store selection:** If the user names a store (a store is a standalone OpenSpec repo registered on this machine) or the work lives in one, run `openspec store list --json` to discover registered store ids, then pass `--store <id>` on the commands that read or write specs and changes (`new change`, `status`, `instructions`, `list`, `show`, `validate`, `archive`, `doctor`, `context`, `schemas`, `view`). Once selected, treat `--store <id>` as sticky for the rest of the workflow. Every unscoped example of those commands below is shorthand: before running it, append the flag. For example, run `openspec status --change "<name>" --json --store "<id>"`, not the unscoped form shown below. Other commands do not take the flag. Hints printed by commands already carry the flag; keep it on follow-ups. Without a store, commands act on the nearest local `openspec/` root.
+
+**Input**: The argument after `/opsx:explore` is whatever the user wants to think about. Could be:
+- A vague idea: "real-time collaboration"
+- A specific problem: "the auth system is getting unwieldy"
+- A change name: "add-dark-mode" (to explore in context of that change)
+- A comparison: "postgres vs sqlite for this"
+- Nothing (just enter explore mode)
+
+---
+
+## The Stance
+
+- **Curious, not prescriptive** - Ask questions that emerge naturally, don't follow a script
+- **Open threads, not interrogations** - Surface multiple interesting directions and let the user follow what resonates. Don't funnel them through a single path of questions.
+- **Visual** - Use ASCII diagrams liberally when they'd help clarify thinking
+- **Adaptive** - Follow interesting threads, pivot when new information emerges
+- **Patient** - Don't rush to conclusions, let the shape of the problem emerge
+- **Grounded** - Explore the actual codebase when relevant, don't just theorize
+
+---
+
+## Planning a Change
+
+When the user is planning a change, guide them toward shared understanding with focused discovery questions. For open-ended discussion, follow the conversation without imposing an interview or a required output.
+
+Before asking a factual question, follow the context discovery below and inspect relevant OpenSpec artifacts, source, tests, docs, and configuration. Do not ask the user to repeat facts you can verify. Summarize relevant findings without reproducing private context or rules. If evidence is missing, conflicting, or inaccessible, state that limitation and ask only for the clarification needed to proceed.
+
+- **Follow dependencies** - Resolve the next blocking decision before its dependent details. For example, clarify the user's outcome and scope before choosing an API or data model. Revisit downstream assumptions when an earlier answer changes. Skip branches that do not matter to this goal.
+- **Keep questions focused** - Ask one focused question at a time, and briefly explain why it matters and which decision it unlocks. Batch questions only if the user asks for a batch; keep them small and group related decisions.
+- **Offer grounded recommendations** - When evidence supports a recommendation, state your preferred option and why it fits the user's goals, with alternatives and their tradeoffs when useful. Do not invent intent, priorities, or external constraints: ask the user when only they can answer. Avoid a fixed question format.
+- **Keep a conversational record** - Track decisions in the conversation, not in files. Separate confirmed decisions from proposed defaults and unresolved questions. Silence is not acceptance. Accepting an answer or a batch of recommendations is not permission to write. Keep file-write confirmation separate from discovery questions and follow the guardrails below.
+
+Stop asking when the user has enough clarity. Let them pause, pivot, or defer a decision; do not exhaust every branch or force a proposal.
+
+For example, after inspecting the relevant code:
+
+```text
+The CLI already uses SQLite and has no remote service. Is sharing state
+across devices in scope? That determines whether local storage is enough.
+If this stays a single-device tool, I recommend keeping SQLite to avoid
+adding a service to operate; shared state would need a separate sync design.
+```
+
+---
+
+## What You Might Do
+
+Depending on what the user brings, you might:
+
+**Explore the problem space**
+- Ask clarifying questions that emerge from what they said
+- Challenge assumptions
+- Reframe the problem
+- Find analogies
+
+**Investigate the codebase**
+- Map existing architecture relevant to the discussion
+- Find integration points
+- Identify patterns already in use
+- Surface hidden complexity
+
+**Compare options**
+- Brainstorm multiple approaches
+- Build comparison tables
+- Sketch tradeoffs
+- Recommend a path (if asked)
+
+**Visualize**
+```
++------------------------------------------+
+|     Use ASCII diagrams liberally         |
++------------------------------------------+
+|                                          |
+|   [State A] -------> [State B]           |
+|       |                                  |
+|       v                                  |
+|   [State C]                              |
+|                                          |
+|   System diagrams, state machines,       |
+|   data flows, architecture sketches,     |
+|   dependency graphs, comparison tables   |
+|                                          |
++------------------------------------------+
+```
+
+**Draw with plain ASCII only** — borders `+` `-` `|`, arrows `-->` `<--` `^` `v`, markers `*` `x`.
+Unicode diagram glyphs can render at different widths across terminals, fonts, and locales, so padded boxes and aligned tables can drift. Keep every diagram character ASCII.
+
+**Surface risks and unknowns**
+- Identify what could go wrong
+- Find gaps in understanding
+- Suggest spikes or investigations
+
+---
+
+## OpenSpec Awareness
+
+You have full context of the OpenSpec system. Use it naturally, don't force it.
+
+### Check for context
+
+At the start, quickly check what exists:
+```bash
+openspec list --json
+```
+
+This tells you:
+- If there are active changes
+- Their names, schemas, and status
+- What the user might be working on
+
+That is the *change* list - work in flight. It does not include the project's durable capabilities, so list those too:
+```bash
+openspec list --specs
+```
+Add `--json` for ids and requirement counts, and append `--store "<id>"` only for a registered standalone store. This is the inventory of what the project already claims to do, and `openspec list` on its own never shows it. To look at one, run `openspec show "<spec-id>" --type spec --json --no-scenarios` (same `--store` rule) - it returns that capability's purpose and requirement texts without pulling the whole spec file into context, and `--type spec` stops a change of the same name from making it ambiguous.
+
+The filtered read is only an overview. Before deciding what is already covered or what should change, read each relevant spec in full, including scenarios, with `openspec show "<spec-id>" --type spec` (same `--store` rule).
+
+Then read the project's own context from the resolved root - `<root.path>/openspec/config.yaml` (or `config.yml`). Use the `root.path` returned above, and skip this if neither file exists:
+- `context`: project background - tech stack, conventions, constraints
+- `rules`: keyed by artifact id - the entries for an artifact apply only when you write that artifact
+
+Ground your thinking in these. They are constraints for you to follow, not content to reproduce: do NOT copy them into the conversation or into any artifact you create.
+
+If the user mentioned a specific change name, read its artifacts for context.
+
+### When no change exists
+
+Think freely. When insights crystallize, you might offer:
+
+- "This feels solid enough to start a change. Want me to create a proposal?"
+- Or keep exploring - no pressure to formalize
+
+If the user asks you to capture the exploration as a new change, transition seamlessly into the requested capture:
+
+1. Run `openspec new change "<name>"` (with `--store <id>` when applicable) before creating any artifacts. Never create a new change directory under `openspec/changes/` by hand; the CLI scaffold creates required metadata such as `.openspec.yaml`. Keep the selected `--store <id>` on every applicable follow-up `status` and `instructions` command.
+2. Run `openspec status --change "<name>" --json` (append the confirmed `--store "<id>"` only for a registered standalone store), then process the requested artifacts in dependency order. For each requested artifact that is `ready`, run `openspec instructions "<artifact-id>" --change "<name>" --json` (append the confirmed `--store "<id>"` only for a registered standalone store). Before creating a requested artifact, evaluate any condition in its own `instruction` against the explored change; record a deliberate skip instead when the condition does not apply. If a requested artifact is blocked by a direct prerequisite the user did not request, run `openspec instructions "<prerequisite-id>" --change "<name>" --json` (append the confirmed `--store "<id>"` only for a registered standalone store) for that prerequisite whether it is `ready` or `blocked`. If its own `instruction` states a condition, evaluate that condition against the explored change and record a deliberate skip only when the condition does not apply. If the condition applies, or the prerequisite is not conditional, treat it as a normal prerequisite and ask before expanding the capture. Do not create an unrequested prerequisite unless the user approves.
+3. Follow the returned `template` and `instruction` fields. Read completed dependency files listed in `dependencies`, and apply `context` and `rules` as constraints without copying them into the artifact. If the instruction delegates creation to a specific skill or command, invoke it; otherwise write the artifact to `resolvedOutputPath`, using the instruction to choose a concrete path when it is a glob. Verify that the selected concrete output exists.
+4. After creating each artifact, re-run `openspec status --change "<name>" --json` (append the confirmed `--store "<id>"` only for a registered standalone store) and continue until every requested artifact is `done`, `skipped`, or was deliberately skipped because its own `instruction` stated a condition that did not apply. Tell the user about a deliberate conditional skip, remember it, and do not reconsider it. Dependencies are enablers, not gates: if a requested artifact is still `blocked` only because you deliberately skipped a conditional prerequisite, run `openspec instructions "<artifact-id>" --change "<name>" --json` (append the confirmed `--store "<id>"` only for a registered standalone store) despite the blocked status, then create it using step 3 only when those recorded conditional skips are its sole missing dependencies. If a requested artifact is blocked by a prerequisite the user did not ask to capture and cannot be conditionally skipped, explain that dependency and ask before expanding the capture.
+
+Capture the artifact(s) the user requested without asking them to invoke another workflow command. If they asked only to start a change, stop after scaffolding and show its status.
+
+### When a change exists
+
+If the user mentions a change or you detect one is relevant:
+
+1. **Resolve and read existing artifacts for context**
+   - Run `openspec status --change "<name>" --json`.
+   - Use `changeRoot`, `artifactPaths`, and `actionContext` from the status JSON.
+   - Read existing files from `artifactPaths.<artifact>.existingOutputPaths`.
+
+2. **Reference them naturally in conversation**
+   - "Your design mentions using Redis, but we just realized SQLite fits better..."
+   - "The proposal scopes this to premium users, but we're now thinking everyone..."
+
+3. **Offer to capture when decisions are made**
+
+   `<capability-path>` is the spec directory relative to `specs/` (for example, `user-auth` or `identity/user-auth`). Preserve an existing capability's full path and follow the project's established organization for new capabilities.
+
+    | Insight Type               | Where to Capture                    |
+    |----------------------------|-------------------------------------|
+    | New requirement discovered | `specs/<capability-path>/spec.md` |
+    | Requirement changed        | `specs/<capability-path>/spec.md` |
+    | Design decision made       | `design.md`                       |
+    | Scope changed              | `proposal.md`                     |
+    | New work identified        | `tasks.md`                        |
+    | Assumption invalidated     | Relevant artifact                   |
+
+   Example offers:
+   - "That's a design decision. Capture it in design.md?"
+   - "This is a new requirement. Add it to specs?"
+   - "This changes scope. Update the proposal?"
+
+4. **The user decides** - Offer and move on. Don't pressure. Don't auto-capture.
+
+---
+
+## What You Don't Have To Do
+
+- Follow a script
+- Ask the same questions every time
+- Produce a specific artifact
+- Reach a conclusion
+- Stay on topic if a tangent is valuable
+- Be brief (this is thinking time)
+
+---
+
+## Ending Discovery
+
+There's no required ending. Discovery might:
+
+- **Flow into a proposal**: "Ready to start? I can create a change proposal."
+- **Result in artifact updates**: "Updated design.md with these decisions"
+- **Just provide clarity**: User has what they need, moves on
+- **Continue later**: "We can pick this up anytime"
+
+When things crystallize, you might offer a summary - but it's optional. Sometimes the thinking IS the value.
+
+---
+
+## Guardrails
+
+- **Don't implement** - Never write code or implement features. Workflow configuration counts too: creating or editing schemas, templates, or `openspec/config.yaml` is a change, not thinking. Creating or updating OpenSpec change artifacts within the confirmed scope is fine, writing anything else is not.
+- **Don't fake understanding** - If something is unclear, dig deeper
+- **Don't rush** - Discovery is thinking time, not task time
+- **Don't force structure** - Let patterns emerge naturally
+- **Don't auto-capture** - Offer to save insights, don't just do it. Read-only commands and tools need no confirmation. Before the first write-capable action—including `openspec new change` or another command that writes files—name the artifacts or files and proposed changes, ask a direct yes/no question, and wait for explicit confirmation in a separate user message. That confirmation covers only the described scope; ask again before expanding it. Answers to design or clarifying questions are never consent to write.
+- **Don't manually scaffold changes** - Never create a new change directory under `openspec/changes/` by hand. Always use `openspec new change "<name>"` (with `--store <id>` when applicable) so required metadata such as `.openspec.yaml` is created before writing artifacts.
+- **Do visualize** - A good diagram is worth many paragraphs
+- **Do explore the codebase** - Ground discussions in reality
+- **Do question assumptions** - Including the user's and your own