xls_doc/docs/superpowers/plans/2026-06-18-docfill-mvp.md

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.