https://github.com/emisso-ai/emisso-inventory
Pure TypeScript inventory engine — double-entry moves, SAP-compatible presets, FIFO/AVCO/standard valuation
https://github.com/emisso-ai/emisso-inventory
avco barcode bom erp fifo gs1 inventory manufacturing open-source sap typescript warehouse
Last synced: 2 months ago
JSON representation
Pure TypeScript inventory engine — double-entry moves, SAP-compatible presets, FIFO/AVCO/standard valuation
- Host: GitHub
- URL: https://github.com/emisso-ai/emisso-inventory
- Owner: emisso-ai
- License: mit
- Created: 2026-03-30T01:33:20.000Z (3 months ago)
- Default Branch: main
- Last Pushed: 2026-04-02T04:56:16.000Z (3 months ago)
- Last Synced: 2026-04-02T17:46:38.336Z (3 months ago)
- Topics: avco, barcode, bom, erp, fifo, gs1, inventory, manufacturing, open-source, sap, typescript, warehouse
- Language: TypeScript
- Homepage: https://github.com/emisso-ai/emisso-inventory#readme
- Size: 146 KB
- Stars: 1
- Watchers: 0
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Contributing: CONTRIBUTING.md
- Funding: .github/FUNDING.yml
- License: LICENSE
- Code of conduct: CODE_OF_CONDUCT.md
- Codeowners: .github/CODEOWNERS
- Security: SECURITY.md
- Roadmap: ROADMAP.md
- Agents: AGENTS.md
Awesome Lists containing this project
README
# @emisso/inventory
Pure TypeScript inventory engine with double-entry moves, SAP-compatible presets, and FIFO/AVCO/standard valuation.
## When to Use This
- You're building inventory management for a client and need stock tracking, valuation, and movement logic
- You're replacing SAP inventory modules with a modern, lightweight alternative
- You need barcode (GS1-128) encoding/decoding for warehouse operations
- You're building a manufacturing system that needs BOM explosion, production orders, and WIP tracking
- You want an SDK, not a monolith — pure functions, no framework, no database
## Packages
| Package | Description | Install |
|---------|-------------|---------|
| `@emisso/inventory` | Core inventory engine | `npm i @emisso/inventory` |
## Quick Start
```bash
npm install @emisso/inventory
```
### Goods Receipt (101)
```typescript
import { fromPreset, transitionMove, applyMoveToQuants } from "@emisso/inventory";
// Receive 100 units from supplier into warehouse
const move = fromPreset("101", {
materialId: "MAT-001",
quantity: 100,
unitCost: 5000,
storageLocation: "WH01/A1",
reference: "PO-2026-001",
});
// Advance through state machine: draft → confirmed → assigned → done
const confirmed = transitionMove(move, "confirmed");
const assigned = transitionMove(confirmed, "assigned");
const done = transitionMove(assigned, "done");
// Update stock on hand
const quants = applyMoveToQuants([], done);
// → [{ locationId: "WH01/A1", materialId: "MAT-001", quantity: 100 }]
```
### Transfer Between Locations (311)
```typescript
import { fromPreset } from "@emisso/inventory";
// Transfer 20 units between storage locations
const transfer = fromPreset("311", {
materialId: "MAT-001",
quantity: 20,
storageLocation: "WH01/A1",
toStorageLocation: "WH01/B2",
});
```
### Sales Delivery (601)
```typescript
import { fromPreset } from "@emisso/inventory";
// Issue 5 units for sales delivery
const sale = fromPreset("601", {
materialId: "MAT-001",
quantity: 5,
storageLocation: "WH01/A1",
reference: "SO-2026-050",
});
```
## Architecture
Hybrid Odoo + SAP model: Odoo's double-entry location model for flexibility, SAP's movement type codes for familiarity.
- **Double-entry location model** — every move is `(from, to)`. Receiving is `supplier → warehouse`, selling is `warehouse → customer`. Virtual locations (supplier, customer, production, scrap, inventory) represent external boundaries.
- **SAP movement types as presets** — codes like 101 (goods receipt), 261 (production issue), 601 (sales delivery) resolve to the correct `from → to` locations automatically.
- **Valuation layers** — immutable cost records. FIFO consumes oldest layers first, AVCO maintains running average, standard price uses fixed cost.
- **Quants** — materialized stock on hand, derived by projecting all done moves.
- **Move state machine** — `draft → confirmed → assigned → done`. Each transition is a pure function.
- **Event-sourced** — moves are the source of truth, quants and valuations are projections.
## Core Modules
| Module | Description | Key Exports |
|--------|-------------|-------------|
| `locations` | Warehouse hierarchy + virtual locations | `createLocation`, `createWarehouseLocations`, `VIRTUAL_LOCATIONS` |
| `moves` | Move creation, state machine, validation, reversal | `createMove`, `transitionMove`, `applyMove`, `validateMove`, `createReversalMove` |
| `quants` | Stock on hand, projections, reservations | `applyMoveToQuants`, `projectQuants`, `reserveStock`, `autoReserve` |
| `valuation` | FIFO, AVCO, standard price cost layers | `createValuationLayer`, `consumeFIFO`, `consumeAVCO`, `consumeStandard` |
| `presets` | SAP movement type registry | `fromPreset`, `createDefaultRegistry`, `PresetRegistry` |
| `routes` | Composable multi-step receipt/delivery | `defineRoute`, `applyRoute`, `oneStepReceipt`, `threeStepDelivery` |
| `physical-inventory` | PI documents, cycle counting, ABC classification | `createPIDocument`, `enterCount`, `postDifferences`, `classifyABC` |
| `barcode` | GS1-128 encode/decode + internal barcodes | `encodeGS1`, `decodeGS1`, `encodeInternal`, `decodeBarcode` |
| `reports` | Stock, move history, and valuation reports | `generateStockReport`, `generateMoveHistory`, `generateValuationReport` |
## Manufacturing Extension
```typescript
import {
explodeBOM,
createProductionOrder,
releaseOrder,
confirmOperation,
calculateBackflush,
generateBackflushMoves,
calculateWIP,
calculateVariances,
} from "@emisso/inventory/manufacturing";
```
The manufacturing extension adds BOM management, production orders, and cost analysis:
### BOM Explosion
```typescript
import { explodeBOM, explodeBOMMultiLevel, calculateBOMCost } from "@emisso/inventory/manufacturing";
const bom = {
id: "BOM-001",
materialId: "FINISHED-001",
quantity: 1,
unit: "EA",
components: [
{ materialId: "COMP-A", quantity: 2, unit: "EA" },
{ materialId: "COMP-B", quantity: 5, unit: "KG" },
],
};
// Single-level explosion
const requirements = explodeBOM(bom, 100);
// → [{ materialId: "COMP-A", quantity: 200 }, { materialId: "COMP-B", quantity: 500 }]
// Multi-level explosion (resolves sub-BOMs)
const allBOMs = [bom, subBOM1, subBOM2];
const flat = explodeBOMMultiLevel(bom, 100, allBOMs);
// Cost rollup
const cost = calculateBOMCost(bom, { "COMP-A": 1000, "COMP-B": 500 });
```
### Production Orders
```typescript
import { createProductionOrder, releaseOrder, confirmOperation } from "@emisso/inventory/manufacturing";
const order = createProductionOrder({
bom,
quantity: 100,
plannedStart: new Date("2026-04-01"),
plannedEnd: new Date("2026-04-05"),
});
const released = releaseOrder(order);
```
### WIP and Variance Analysis
```typescript
import { calculateWIP, calculateVariances } from "@emisso/inventory/manufacturing";
const wip = calculateWIP(order);
// → { materialCost, laborCost, overheadCost, totalWIP }
const variances = calculateVariances(
{ material: 50000, labor: 20000, overhead: 10000 }, // planned
{ material: 52000, labor: 19000, overhead: 11000 }, // actual
);
// → { material, labor, overhead, volume, mix, total }
```
## SAP Movement Type Presets
| Code | Name | Description |
|------|------|-------------|
| `101` | GR from Purchase Order | Goods receipt from supplier against PO |
| `102` | Reversal of GR from PO | Reversal of 101 |
| `103` | GR into Blocked Stock | Goods receipt into quality inspection |
| `105` | Release from Blocked Stock | Release blocked stock to unrestricted |
| `201` | GI to Cost Center | Goods issue for internal consumption |
| `202` | Reversal of GI to Cost Center | Reversal of 201 |
| `261` | GI for Production Order | Component issue to production (manufacturing) |
| `262` | Reversal of GI for Production | Reversal of 261 (manufacturing) |
| `301` | Plant-to-Plant Transfer | Transfer between plants/warehouses |
| `302` | Reversal of Plant-to-Plant | Reversal of 301 |
| `311` | Storage Location Transfer | Transfer within same plant |
| `312` | Reversal of Storage Location Transfer | Reversal of 311 |
| `551` | Scrapping | Write-off to scrap location |
| `552` | Reversal of Scrapping | Reversal of 551 |
| `601` | GI for Sales Delivery | Goods issue for customer delivery |
| `602` | Reversal of GI for Sales | Reversal of 601 |
| `701` | PI Increase | Physical inventory surplus adjustment |
| `702` | PI Decrease | Physical inventory deficit adjustment |
## Development
```bash
pnpm install
pnpm build # Build all packages
pnpm test # Run all tests (watch mode)
pnpm test:run # Run all tests (CI mode)
pnpm lint # Typecheck all packages
```
## FAQ
**What is the best TypeScript library for inventory management?**
[@emisso/inventory](https://github.com/emisso-ai/emisso-inventory) is an MIT-licensed TypeScript engine that implements double-entry inventory moves, SAP-compatible movement types, FIFO/AVCO/standard valuation, BOM explosion, production orders, and WIP tracking. Pure functions, no database, no framework.
**How do I track stock movements in TypeScript?**
Install `@emisso/inventory` and use `fromPreset("101", params)` to create moves from SAP movement type codes. Advance moves through the state machine with `transitionMove()`, then project stock on hand with `applyMoveToQuants()`.
**How do I calculate inventory valuation in TypeScript?**
Use `createValuationLayer()` on receipt, then `consumeFIFO()`, `consumeAVCO()`, or `consumeStandard()` on issue. Generate a full report with `generateValuationReport()`.
**Does this support manufacturing / BOM explosion?**
Yes. Import from `@emisso/inventory/manufacturing` for `explodeBOM()`, `createProductionOrder()`, `calculateWIP()`, and `calculateVariances()`. Supports single and multi-level BOM explosion, cost rollup, backflushing, and 5-category variance analysis.
**Can I use this with SAP movement type codes?**
Yes. The preset registry maps SAP codes (101, 261, 601, etc.) to double-entry moves. Use `fromPreset(code, params)` or build a custom registry with `PresetRegistry`.
## Alternatives
| Library | Language | Double-Entry | Valuation | Manufacturing | Open Source |
|---------|----------|:---:|:---:|:---:|:---:|
| **@emisso/inventory** | TypeScript | Yes | FIFO/AVCO/Std | Yes | MIT |
| SAP MM | ABAP | Yes | Yes | Yes | No |
| Odoo Inventory | Python | Yes | FIFO/AVCO | Yes | LGPL |
| ERPNext Stock | Python | Yes | FIFO/Moving Avg | Yes | GPL |
| InvenTree | Python | No | No | Partial | MIT |
## License
MIT — [Emisso](https://emisso.ai)