Nexus — Rule Registry | Uued Viljapuuaiad

1. Registry Overview

874 total rules across 15 rule types, 11 formula functions, 6 engine rule classes, and 5 use case domains.

2. Formula Language Specification

The Wormwood formula language is a deterministic, sandboxed expression language parsed by FormulaParser. It supports two modes: standalone (direct attribute paths) and legacy Excel (cell references with mappings). All formula evaluation is side-effect-free: no loops, no I/O, no mutable state. The same input always produces the same output.

2.1 Operator Precedence (Lowest to Highest)

Level	Operators	Associativity	Description
1	`? :`	Right	Ternary conditional
2	`\`	\		Left	Logical OR
3	`&&`	Left	Logical AND
4	`==` `!=` `>` `<` `>=` `<=`	Left	Comparison
5	`+` `-`	Left	Addition, subtraction
6	`/`	Left	Multiplication, division
7	`^`	Right	Exponentiation
8	`!` `NOT`	Unary	Boolean negation
9	`()`	n/a	Grouping

2.2 Built-in Functions

Function	Signature	Description	Example
`SUM`	`SUM(a, b, ...)`	Sum of non-null arguments	`SUM(capex.racks, capex.ups, capex.gen)`
`ROUNDUP`	`ROUNDUP(value [, decimals])`	Ceiling round; optional precision	`ROUNDUP(power.it_load_kw)`
`ROUND`	`ROUND(value [, decimals])`	Standard rounding; default 0 decimals	`ROUND(score.total, 2)`
`MAX`	`MAX(a, b, ...)`	Maximum of non-null arguments	`MAX(score.a, score.b)`
`MIN`	`MIN(a, b, ...)`	Minimum of non-null arguments	`MIN(budget.low, budget.high)`
`IF`	`IF(cond, true_val, false_val)`	Conditional value selection	`IF(entity.status == 'Active', 1, 0)`
`ABS`	`ABS(value)`	Absolute value	`ABS(delta.variance)`
`SQRT`	`SQRT(value)`	Square root	`SQRT(power.total_kw)`
`IN`	`IN(value, opt1, opt2, ...)`	Membership test against value list	`IN(entity.material, 'Carbon Steel', 'Duplex')`
`REGEX_MATCH`	`REGEX_MATCH(text, pattern)`	Regex match against pattern	`REGEX_MATCH(entity.tag, '^[A-Z]{2}-')`
`TOPK_AVG`	`TOPK_AVG(k, v1, v2, ...)`	Average of top-K non-null values	`TOPK_AVG(3, s.a, s.b, s.c, s.d)`

2.3 Literals and Data Types

Type	Syntax	Internal Representation
Number	`42`, `3.14`, `0.615385`	Python `float`
String	`'fixed'` or `"negotiable"`	Python `str`
Boolean	`TRUE`, `FALSE`	`1.0` / `0.0`
Null	`null`	Python `None`
Attribute path	`entity.tag`, `budget.amount`	Dot-path resolution against context dict
Cell reference	`$C83`, `I57`	Legacy mode only; resolved via `cell_mappings`

2.4 Expression Modes

Standalone Mode (Current Standard)

Formulas use direct attribute paths: assumptions.rack_cost rack.total_racks 1000. The parser resolves paths against the calculation context dictionary. This is the mode used by all NSD rulesets.

Legacy Excel Mode (Backward Compatibility)

Formulas use cell references with an explicit mapping: =C75 I57 1000 with cell_mappings = {"C75": "assumptions.rack_cost", "I57": "rack.total_racks"}. This mode exists for Pyrometrix TCO rules imported directly from Excel spreadsheets. New rulesets MUST NOT use this mode.

Class	Enum Value	Default Priority	Purpose	Execution Phase
Validation	`VALIDATION`	200+	Check inputs, enforce constraints, flag errors	First -- reject bad data before calculations
Consolidation	`CONSOLIDATION`	150+	Apply baseline fixes, resolve defaults, normalise	Second -- clean data for downstream rules
Calculation	`CALCULATION`	100+	Core business logic: CAPEX, OPEX, power, scoring	Third -- primary value computation
Adjustment	`ADJUSTMENT`	50+	Technology-specific tweaks, overrides, modifiers	Fourth -- refine calculation results
Escalation	`ESCALATION`	10+	Time-based escalation (year-over-year growth, decay)	Fifth -- apply temporal factors
Aggregation	`AGGREGATION`	1	Final summing, total computation, report output	Last -- produce final results

Type	Directory	Count	Description	Technologies
`capex`	`capex/`	65	Capital expenditure calculations: racks, cooling, UPS, generators, electrical, site prep, engineering	traditional, dlc, rdhx, grc
`opex`	`opex/`	148	Operational expenditure: power, maintenance, staffing, PUE factors, year-over-year escalation	traditional, dlc, rdhx, grc
`power`	`infrastructure/`	8	Electrical power chain: IT load, cooling, UPS, total DC power	all
`infrastructure`	`infrastructure/`	3	Rack counts, floor space, power density	all
`energy`	`infrastructure/`	4	Energy efficiency: PUE, annual consumption, carbon	all
`tco`	`tco/`	10	Total cost of ownership: year summation, NPV, 10-year horizon	traditional, dlc, rdhx, grc

Type	Directory	Count	Description	Entity Classes
`edr_validation`	`edr/`	19	Tag format, valve size, pressure rating, power rating, material standard, safety classification, voltage, instrument range, completeness scoring, quality tier	Valve, Pipeline, Equipment, Electrical, Instrument, Safety
`validation`	`edr/`	12	Consolidation and cross-entity validation: duplicates, orphan detection	All

Type	Directory	Count	Description	Countries
`nesto_compliance`	`nesto/`	17	Passport, nationality, visa type, emirate, sponsor, medical fitness, biometrics, occupation code, contract dates, salary range, accommodation type, insurance, WPS, bank, labour card, MOHRE approval, Emirates ID	UAE, KSA, BH

Type	Directory	Count	Description
`scoring`	`freelance/`	10	Job opportunity scoring: budget clarity, competition level, deadline pressure, scope clarity, tech stack match, client history, rate fit, recency, portfolio relevance, final composite
`policy`	`freelance/`	11	Pricing policy: minimum hourly rate, project floor, platform fee adjustment, currency normalisation, rush surcharge, complexity multiplier
`assignment`	`freelance/`	4	Tier assignment: gold/silver/bronze based on composite score thresholds

Type	Directory	Count	Description
`pfp_clearance`	`pfp/`	537	Product clearance rules: compliance checks, compatibility matrices, regulatory clearance per jurisdiction
`pfp_selection`	`pfp/`	9	Product selection logic: technology matching, priority ordering
`pfp_validation`	`pfp/`	17	Profile input validation: required fields, range checks, format validation

3. Engine Rule Classes

The RuleEngine (wormwood/core/rule_engine.py) classifies rules into six execution classes, each with a default priority band. Rules execute in descending priority order within a calculation pass.

Class Enum Value Default Priority Purpose Execution Phase

Validation VALIDATION 200+ Check inputs, enforce constraints, flag errors First -- reject bad data before calculations

Consolidation CONSOLIDATION 150+ Apply baseline fixes, resolve defaults, normalise Second -- clean data for downstream rules

Calculation CALCULATION 100+ Core business logic: CAPEX, OPEX, power, scoring Third -- primary value computation

Adjustment ADJUSTMENT 50+ Technology-specific tweaks, overrides, modifiers Fourth -- refine calculation results

Escalation ESCALATION 10+ Time-based escalation (year-over-year growth, decay) Fifth -- apply temporal factors

Aggregation AGGREGATION 1 Final summing, total computation, report output Last -- produce final results

Why Six Classes?

Each class represents a logical phase in the calculation pipeline. Validation must run before Calculation so that invalid inputs fail early. Consolidation normalises data (e.g., applying default material for valves without one specified). Adjustments apply after core calculations so technology-specific modifiers do not pollute the base logic. Escalation applies last because it multiplies already-computed values by time factors. Aggregation sums everything. This order is deterministic and guaranteed regardless of rule registration order.

4. Rule Type Registry

Each JSON rule file declares a type field that classifies the rule into a domain. The following 15 rule types exist across 25 JSON files in wormwood/rules/.

4.1 Infrastructure Domain (Pyrometrix TCO)

Type Directory Count Description Technologies

capex capex/ 65 Capital expenditure calculations: racks, cooling, UPS, generators, electrical, site prep, engineering traditional, dlc, rdhx, grc

opex opex/ 148 Operational expenditure: power, maintenance, staffing, PUE factors, year-over-year escalation traditional, dlc, rdhx, grc

power infrastructure/ 8 Electrical power chain: IT load, cooling, UPS, total DC power all

infrastructure infrastructure/ 3 Rack counts, floor space, power density all

energy infrastructure/ 4 Energy efficiency: PUE, annual consumption, carbon all

tco tco/ 10 Total cost of ownership: year summation, NPV, 10-year horizon traditional, dlc, rdhx, grc

4.2 EDR Domain (Entity Data Registry)

Type Directory Count Description Entity Classes

edr_validation edr/ 19 Tag format, valve size, pressure rating, power rating, material standard, safety classification, voltage, instrument range, completeness scoring, quality tier Valve, Pipeline, Equipment, Electrical, Instrument, Safety

validation edr/ 12 Consolidation and cross-entity validation: duplicates, orphan detection All

4.3 Nesto Domain (Worker Compliance)

Type Directory Count Description Countries

nesto_compliance nesto/ 17 Passport, nationality, visa type, emirate, sponsor, medical fitness, biometrics, occupation code, contract dates, salary range, accommodation type, insurance, WPS, bank, labour card, MOHRE approval, Emirates ID UAE, KSA, BH

4.4 Freelance Pipeline Domain

Type Directory Count Description

scoring freelance/ 10 Job opportunity scoring: budget clarity, competition level, deadline pressure, scope clarity, tech stack match, client history, rate fit, recency, portfolio relevance, final composite

policy freelance/ 11 Pricing policy: minimum hourly rate, project floor, platform fee adjustment, currency normalisation, rush surcharge, complexity multiplier

assignment freelance/ 4 Tier assignment: gold/silver/bronze based on composite score thresholds

4.5 PFP Domain (Product Fit Profile)

Type Directory Count Description

pfp_clearance pfp/ 537 Product clearance rules: compliance checks, compatibility matrices, regulatory clearance per jurisdiction

pfp_selection pfp/ 9 Product selection logic: technology matching, priority ordering

pfp_validation pfp/ 17 Profile input validation: required fields, range checks, format validation

5. Rule JSON Schema

Every rule in wormwood/rules//.json follows this schema. Fields marked Required are mandatory for all rule types. Fields marked Domain are present in specific domains.

Field	Type	Status	Description
`id`	string	Required	Unique rule identifier. Convention: `{domain}_{category}_{seq}_{slug}`
`name`	string	Required	Human-readable rule name
`type`	string	Required	Rule type from Section 4 registry
`priority`	integer	Required	Execution priority (higher = runs first)
`technology`	string	Required	Technology scope: `traditional`, `dlc`, `rdhx`, `grc`, `edr`, `nesto`, `pipeline`, or `all`
`formula`	string	Required	Wormwood formula expression (Section 2)
`output`	string	Required	Dot-path where result is stored in context
`description`	string	Required	Human-readable description of what the rule does
`enabled`	boolean	Required	Whether the rule is active
`excel_source`	string	Domain	Pyrometrix only: original Excel cell reference
`severity`	string	Domain	EDR/Nesto: `ERROR`, `WARNING`, `INFO`
`applies_to`	string	Domain	EDR: entity class filter (`Valve`, `Pipeline`, `All`)
`countries`	array	Domain	Nesto: ISO country codes where rule applies
`edr_source`	string	Domain	EDR: source table or property reference
`validation`	object	Domain	Expected range, baseline value, tolerance percentage, test cases

6. Technology Scoping

Rules are scoped to a technology via the technology field. When the engine evaluates rules for a given technology context, only rules matching that technology (or all) are executed.

Technology	Domain	Description
`traditional`	Pyrometrix	Air-cooled data centre (baseline comparison)
`dlc`	Pyrometrix	Direct liquid cooling
`rdhx`	Pyrometrix	Rear-door heat exchanger
`grc`	Pyrometrix	Green Revolution Cooling immersion
`edr`	EDR	Entity Data Registry (Wormwood core)
`nesto`	Nesto	Worker compliance, UAE/KSA/BH jurisdictions
`pipeline`	Freelance	Job scoring and pricing pipeline
`all`	Cross-domain	Infrastructure and power rules shared across all technologies

7. Registry Versioning

This registry is versioned independently from other Nexus documents. The NSD references the registry version it was built against. If a new rule type or formula function is added, the registry version increments and all NSD references must be updated.

Version	Date	Changes
RR-1.0	2026-05-02	Initial registry: 874 rules, 15 types, 11 functions, 6 engine classes. Extracted from codebase implementation.

Referencing This Registry

The NSD rulesets section references registry version via: "rule_registry_version": "RR-1.0". The DevOps Service validates that all rule types used in the NSD are declared in the referenced registry version. Undeclared rule types cause deployment rejection.