Stellar Throne Devlog #10 — From Bug Fixes to Breakthroughs

Yesterday brought significant forward momentum on Stellar Throne, a 4X strategy title utilizing Godot for the UI layer and Zig for performance-critical simulation work. After confirming the dual-engine design maintained visual consistency, the session focused on resolving critical issues and adding major missing functionality.

Fleet Movement: Multi-Hop Solution

An initial problem prevented fleets from progressing beyond their first waypoint. Multi-system journeys would halt prematurely.

Two factors caused this:

1. The Zig backend lacked multi-hop continuation logic
2. The has_planned_route flag wasn't correctly set during deserialization

Both issues were resolved by implementing continuation logic in the Zig fleet arrival handler and correcting route flag inference from the route array. Fleets now traverse all waypoints successfully.

Event Manager Restoration

The "Salvage the Past" event — providing narrative flavor and resource rewards at game start — failed to trigger. Investigation revealed the Event Manager attempted loading from an outdated JSON format instead of the migrated TOML system.

The fix involved replacing hardcoded JSON loading with a TOML-based approach via the Config Manager, implementing automatic case conversion, and correcting the autoload initialization sequence. Moving Config Manager earlier in the startup sequence resolved the timing issue.

Research System Restructuring

The research implementation contained multiple problems:

• Progress failed to persist after save/load cycles
• Tech completion used incorrect cost calculations
• Serialization key mismatches (active_tech vs. active_tech_id)
• Corrupted deserialization from nested dictionaries
• Progress accumulated beyond 100%
• Incompatible flat structures for Godot integration

The serialization layer was reconstructed, and ResearchState, SimEmpire, and TurnSimulator were restructured for consistent persistence.

Cost calculation errors stemmed from flawed tier-matching logic. The Zig backend inferred costs from tiers rather than fetching actual values from TOML configuration. Switching to proper ID-based lookups resolved this.

Tech effect application was broken — the simplified completeTech() function unlocked technologies without applying effects or dispatching notifications. A temporary workaround in TurnSimulationService post-processes completed techs and invokes the full Godot-side applyTechnologyEffects() method. This approach is documented in TODO_TECH_EFFECTS.md for a proper 15-20 hour implementation.

Strategic Roadmap Development

Following the bug-fixing phase, attention shifted toward structured long-term planning. The Zig backend currently features 10 simplified systems. To achieve full parity with Godot, five planning documents were created:

1. Zig Implementation Plan — 13-week roadmap with per-system breakdowns, estimating 360-450 total hours
2. Zig Parity Roadmap — Executive overview showing 8 complete systems, 10 simplified, moving from 65% tolerance to near-zero parity
3. Parity Test Examples — Deterministic test specifications with exact RNG seeding
4. Zig Parity Progress — Session tracking with milestone checklists and velocity metrics
5. Session Workflow Guide — Practical start/during/end checklists for development continuity

Phase Five Completion: Construction Implementation

The Construction System was implemented, supporting both turn-based building and production-driven shipbuilding.

New components include:

• SimConstruction.zig with ConstructionOrder and ConstructionQueue
• Extended SimGalaxy for build and ship queue management
• Processing logic in TurnSimulator

Each order tracks 13 parameters covering progress, duration, and costs. Queue operations follow FIFO principles, with support for both building completion and ship production.

Development completed 8 hours — 33% faster than the 12-16 hour estimate.

Test Results:

• 339 Zig unit tests: Passing
• 739/740 GUT integration tests: Passing

Zig parity: 1/7 phases complete (14%)

Construction System Issues & Resolutions

Three deeper problems emerged:

1. Missing system references — Planets lacked system_id after deserialization. Resolution: Set the value during StarSystem.from_dict()
2. Building type errors — Type strings failed to deserialize properly. Temporary solution: Queue-preservation workaround implemented
3. Incorrect building spawning — Empty item types triggered wrong building creation. Fix: State preservation until full parity implementation

Documentation Improvements

The RESUME.md file exceeded 2,000 lines, straining context windows. Optimization included:

• Archiving sessions 1-59 to separate storage
• Reducing RESUME.md to 400 lines (80% reduction)
• Creating two specialized Claude agents:
  • Resume Writer Agent — auto-archives when context exceeds 150K tokens or at session end
  • Resume Reader Agent — summarizes project state at startup

Technical Summary

The session produced 13 commits and over 1,000 lines of code changes:

• Fleet multi-hop fix: 34 lines
• Event system TOML migration: 63 lines
• Autoload dependency correction: 1 line
• Research persistence & cost fixes: 128 lines
• Tech effect workaround: 53 lines
• Planning documents: 2,000+ lines (5 new files)
• Construction system: 454 lines
• Construction bug fixes: 108 lines
• Resume refactor: 1,500 archived lines + 2 Claude agents

Current Status

• Fleet navigation through multi-waypoint routes functional
• Event triggering restored at game initialization
• Research completion respects correct costs and applies technology effects
• Construction system fully operational in Zig
• One of seven parity phases completed (14%)
• Documentation systems streamlined with automation

Development has shifted from "fixing Zig backend issues" to "systematically implementing complete system parity." The structured roadmap provides a framework for achieving 100% Zig simulation parity within 13 weeks.

Next Phase: Phase Nine — Combat Resolution (24-32 hour estimate)