# Docfill MVP Implementation Plan

> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.

**Goal:** Build a minimal Go CLI that fills `.docx` and `.xlsx` templates from Excel or SQLite rows.

**Architecture:** A single internal package loads JSON config, reads rows from Excel or SQLite, renders placeholders into docx/xlsx files, and exposes `Run`. A tiny CLI parses `run --config`.

**Tech Stack:** Go, `excelize` for `.xlsx`, `modernc.org/sqlite` for SQLite, standard `archive/zip` for `.docx`.

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### Task 1: Tests First

**Files:**
- Create: `internal/docfill/docfill_test.go`

- [ ] Write tests for Excel row reading, SQLite row reading, xlsx rendering, docx rendering, and full config execution.
- [ ] Run `go test ./...` and confirm it fails because the package implementation does not exist yet.

### Task 2: Minimal Library

**Files:**
- Create: `internal/docfill/docfill.go`

- [ ] Implement config parsing.
- [ ] Implement Excel and SQLite row readers.
- [ ] Implement placeholder replacement.
- [ ] Implement xlsx and docx rendering.
- [ ] Implement `Run(configPath string) error`.

### Task 3: CLI

**Files:**
- Create: `cmd/docfill/main.go`

- [ ] Parse `docfill run --config task.json`.
- [ ] Print clear errors to stderr.
- [ ] Exit non-zero on failure.

### Task 4: Verify

- [ ] Run `go test ./...`.
- [ ] Run `go build ./cmd/docfill`.
- [ ] Keep README usage minimal.