U-APS

Advanced Production Scheduling — Hybrid Rust/C# scheduling system

Overview

U-APS is a production scheduling system that combines a Rust optimization engine with a C# SDK.

Input (JSON/Excel) → Scheduling Engine → Output (JSON/Excel)

Architecture

┌──────────────────────────────────────────────┐
│                   U-APS                       │
├──────────────────────────────────────────────┤
│  APS Engine (Rust)                            │
│  ├── 7 scheduling algorithms                 │
│  ├── FFI interface (5 C-ABI functions)       │
│  └── Built on u-schedule + u-metaheur        │
├──────────────────────────────────────────────┤
│  UAPS.SDK (C#)          │  UAPS.CLI (C#)     │
│  ├── Fluent API          │  ├── JSON I/O      │
│  ├── SchedulerClient     │  └── Excel I/O     │
│  └── NativeLoader        │                    │
└──────────────────────────┴────────────────────┘

Installation

CLI (Recommended)

# Install as dotnet tool
dotnet tool install -g UAPS.CLI

# Usage
uaps input.json output.json
uaps input.xlsx output.xlsx

# With dispatching strategy
uaps input.json output.json --strategy SPT
uaps input.json output.json --strategy EDD --tie-breaker FIFO

Or download standalone binaries from GitHub Releases.

SDK

dotnet add package UAPS.SDK

using UAPS.SDK.Client;
using UAPS.SDK.Interop;
using UAPS.SDK.Models;

await NativeLoader.EnsureLoadedAsync();

var job = Job.Create("J1")
    .WithPriority(1)
    .WithDueDate(DateTime.Now.AddHours(8));

job.Operations.Add(
    Operation.Create("O1", "J1", 1)
        .WithTime(0, 60_000, 0)
        .WithEquipment("M1")
        .WithMaterial("MAT-001", 10.0)
);

var resource = Resource.CreateEquipment("M1", "Machine 1");

var client = new SchedulerClient();
var request = new ScheduleRequest
{
    Jobs = [job],
    Resources = [resource],
    DispatchingConfig = new DispatchingConfig
    {
        PrimaryRule = "EDD",
        TieBreaker = "SPT"
    }
};
var result = client.Schedule(request);

Console.WriteLine($"Makespan: {result.Schedule.MakespanMs}ms");

Features

Scheduling Algorithms

Algorithm	Type	Best For
Simple	Dispatching rule	Fast baseline, small problems
GeneticAlgorithm	Metaheuristic	Medium problems (30-200 ops)
Production	GA + extensions	Real manufacturing with setup/split/overlap
Dynamic	Time-fence	Rescheduling with frozen horizons
CpSat	Constraint Programming	Exact solutions for small problems
Hybrid	GA + SA	Large problems needing escape from local optima
Auto	Adaptive	Selects algorithm based on problem characteristics

Dispatching Rules

Rule	Description	Best For
FIFO	First In First Out	Fair scheduling
SPT	Shortest Processing Time	Minimize avg flow time
LPT	Longest Processing Time	Load balancing
EDD	Earliest Due Date	Minimize tardiness
SLACK	Minimum Slack Time	Urgent jobs
CR	Critical Ratio	Balance due dates
PRIORITY	Job Priority	Explicit prioritization
LWKR	Least Work Remaining	Quick completions
MWKR	Most Work Remaining	Complex jobs first
MOPNR	Most Operations Remaining	Complex jobs first
RANDOM	Random	Baseline comparison

Constraint Management

• Resource Constraints: Equipment, workers, calendars, shifts
• Material Constraints: BOM, stock levels, safety stock, lead times
• Time Constraints: Due dates, earliest start, time windows
• Setup Optimization: Setup matrices, campaign scheduling
• Multi-Site Scheduling: Site transitions with inter-site transit times

Advanced Features

• Skill Matrix: Worker proficiency tracking with learning curves
• Certification Matrix: Worker certifications with expiry management
• Crew Management: Team assignments with shift schedules
• Rescheduling Events: 18 event types for dynamic adjustments
  • Equipment: Breakdown, Recovery, Maintenance, Efficiency change
  • Material: Shortage, Delay, Arrival
  • Worker: Unavailable, Available, Skill change
  • Quality: Defect, Inspection delay
  • Order: Delay, Urgent order, Cancellation, Due date/Quantity/Priority change

Analytics

• KPIs: Makespan, utilization, tardiness, MCE
• CTP (Capable-To-Promise): Delivery date promises
• What-If Analysis: Scenario comparison
• Bottleneck Detection: Resource utilization analysis

FFI Interface

Five C-ABI functions for external consumption:

Function	Purpose
uaps_schedule()	Schedule with algorithm selection + KPI + metrics
uaps_validate()	Pre-flight input validation
uaps_reschedule()	Event-driven rescheduling
uaps_version()	Engine version string
uaps_free_string()	Free allocated string memory

Building

Requirements

• Rust 1.70+
• .NET 9.0+ SDK

Commands

# Full build
.\scripts\build.ps1 -Configuration Release

# Run tests
.\scripts\test.ps1

# Run samples
.\scripts\run-samples.ps1 -Report

Individual Components

# Rust Engine only
cd engine
cargo build --release
cargo test

# C# SDK only
cd sdk
dotnet build -c Release
dotnet test

Project Structure

U-APS/
├── engine/                 # APS engine (Rust)
│   └── src/
│       ├── models/         # Job, Operation, Resource, Material, etc.
│       ├── scheduler/      # Scheduling algorithms, KPI, rescheduling
│       ├── ga/             # Genetic algorithm with dual-vector encoding
│       ├── cp/             # Constraint programming solver
│       ├── benchmark/      # Standard JSP/FJSSP instances
│       ├── validation/     # Input validation
│       └── ffi.rs          # C-ABI FFI interface
├── sdk/
│   ├── UAPS.SDK/           # C# SDK
│   │   ├── Models/         # Domain models
│   │   ├── Client/         # SchedulerClient
│   │   ├── Simulation/     # SimulationSession
│   │   └── Analytics/      # WhatIfSimulator
│   ├── UAPS.CLI/           # Command-line tool
│   └── UAPS.SDK.Tests/     # C# tests
├── samples/                # Example scenarios
└── docs/                   # Documentation

Samples

Sample	Description
001-simple	Basic single job scheduling
002-multi-job	Multiple jobs with priorities
003-due-dates	Due date constraints and violations
004-setup-matrix	Setup time optimization
005-multi-resource	Multi-resource operations
006-parallel-machines	Parallel machine scheduling
007-complex-flow	Complex multi-job flow

Test Results

• Engine Tests: 373 passed (Rust)
• FFI Tests: 12 integration tests
• SDK Tests: 78 passed (C#)

License

MIT License — see LICENSE.

Dependencies

• u-schedule — Scheduling framework
• u-metaheur — Metaheuristic optimization
• u-numflow — Mathematical primitives