Sandbox & Limits

Lua chip scripts run in a deterministic sandbox to ensure game stability and prevent abuse.

Instruction Limits

Phase	Budget
Initialization (module-level code)	500,000 instructions (default)
Per tick (coroutine + tick + events)	50,000 instructions (default)

In the StationeersLua mod configuration (BepInEx / in-game mod panel), category [Lua VM]:

Setting	Default	Notes
InitInstructionLimit	500000	Startup budget (module-level code, first resume, legacy serialize/deserialize hooks)
TickInstructionLimit	50000	Per game tick, per chip

Values are clamped between 1,000 and 100,000,000. Only the simulation host runs Lua chips (dedicated server or session host), so in multiplayer these settings apply from the host or server config, not from joining clients.

Exceeding limits triggers a runtime error on the chip (red light on the housing).

ic.persist size limits

Category [Lua Persist] in the same mod configuration panel:

Setting	Default	Range
MaxKeyLength	128	1 - 4096
MaxValueLength	8192	1 - 1,048,576
MaxTotalBytes	32768	256 - 4,194,304

Server-authoritative (same host rule as instruction limits). See Save/Load Persistence.

Available Libraries

Library	Notes
math	Full: math.sin, math.floor, math.random, etc.
string	Full: string.format, string.sub, string.find, etc.
table	Full: table.insert, table.remove, table.sort, etc.
coroutine	Full: coroutine.create, coroutine.resume, coroutine.yield, etc. sleep/yield work inside user coroutines.
utf8	UTF-8 string handling
os.clock	High-resolution timer
os.time	Current Unix timestamp
os.date	Date/time formatting
os.difftime	Time difference
pcall, xpcall	Protected calls
tonumber, tostring, type	Standard conversions
pairs, ipairs, next	Table iteration
select, unpack, rawget, rawset	Table utilities
load	Dynamic code loading (from strings only)
util.json	JSON encode/decode

Blocked Libraries

Blocked	Reason
debug	Intentionally unavailable on chips - the Lua debug library exposes internal VM state and is not available in the chip sandbox
io	Filesystem access
package	Filesystem module loading (replaced by require() from data network)
dofile, loadfile	Filesystem access
os.execute, os.exit, os.remove, os.rename	Process/filesystem mutation
os.tmpname, os.setlocale, os.getenv	System interaction

Runtime Behavior

• Scripts run as Lua coroutines, allowing sleep() and yield() to pause execution
• Async C# work during tick is rejected — only coroutine suspension is supported
• print(...) writes to the Lua Debugger Logs tab (per-chip, bounded, cleared on power cycle)
• File I/O, module loading, and process-affecting operations are disabled