graphforge 0.1.2

Composable graph tooling for analysis, construction, and refinement

GraphForge

Composable graph tooling for analysis, construction, and refinement

A lightweight, embedded, openCypher-compatible graph engine for research and investigative workflows

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Table of Contents

• Why GraphForge?
• Installation
• Quick Start
• Core Concepts
• Python API Reference
• Cypher Query Language
• Usage Patterns
• Examples
• Advanced Features
• Design Principles
• Contributing
• License

---

Why GraphForge?

Modern data science and ML workflows increasingly produce graph-shaped data—entities and relationships extracted from text, tables, and LLM outputs. Yet practitioners face a painful choice:

	NetworkX	GraphForge	Production DBs (Neo4j, Memgraph)
Durability	Manual serialization	✓ SQLite backend	✓ Persistent
Query language	None	openCypher subset	Full Cypher
Operational overhead	Minimal	Minimal (embedded)	High (services, config)
Notebook-friendly	✓	✓	✗
Iterative analysis	✓	✓	Poor

GraphForge fills the gap—embedded, durable, and declarative—without running external services.

We are not building a database for applications. We are building a graph execution environment for thinking.

Use Cases

Knowledge Graph Construction

• Extract entities and relationships from unstructured text
• Build and query knowledge graphs from documents
• Iteratively refine graph structures during analysis

Data Lineage and Provenance

• Track data transformations and dependencies
• Query upstream and downstream impacts
• Maintain audit trails of analytical workflows

Network Analysis in Notebooks

• Analyze social networks, citation graphs, dependency graphs
• Persist analysis results alongside code
• Share reproducible graph analyses

LLM-Powered Graph Generation

• Store LLM-extracted entities and relationships
• Query structured outputs from language models
• Build hybrid retrieval systems with graph context

---

Installation

# Using uv (recommended)
uv add graphforge

# Using pip
pip install graphforge

Requirements: Python 3.10+

Dependencies: pydantic>=2.6, lark>=1.1, msgpack>=1.0

---

Quick Start

5-Minute Introduction

from graphforge import GraphForge

# Create an in-memory graph
db = GraphForge()

# Option 1: Python API (imperative)
alice = db.create_node(['Person'], name='Alice', age=30)
bob = db.create_node(['Person'], name='Bob', age=25)
db.create_relationship(alice, bob, 'KNOWS', since=2020)

# Option 2: Cypher queries (declarative)
db.execute("CREATE (c:Person {name: 'Charlie', age: 35})")
db.execute("MATCH (a:Person {name: 'Alice'}), (c:Person {name: 'Charlie'}) CREATE (a)-[:KNOWS]->(c)")

# Query the graph
results = db.execute("""
    MATCH (p:Person)-[:KNOWS]->(friend:Person)
    WHERE p.age > 25
    RETURN p.name AS person, friend.name AS friend
    ORDER BY p.age DESC
""")

for row in results:
    print(f"{row['person'].value} knows {row['friend'].value}")
# Output:
# Charlie knows Alice
# Alice knows Bob
# Alice knows Charlie

Persistent Graphs

# Create a persistent graph
db = GraphForge("my-research.db")

# Add data (persists automatically on close)
db.execute("CREATE (p:Paper {title: 'Graph Neural Networks', year: 2021})")
db.close()

# Later: reload the same graph
db = GraphForge("my-research.db")
results = db.execute("MATCH (p:Paper) RETURN p.title AS title")
print(results[0]['title'].value)  # Graph Neural Networks

---

Core Concepts

Nodes and Relationships

Nodes represent entities with:

• Labels: Categories like Person, Document, Gene
• Properties: Key-value attributes (strings, integers, booleans, lists, maps)
• IDs: Auto-generated unique identifiers

Relationships connect nodes with:

• Type: Semantic connection like KNOWS, CITES, REGULATES
• Direction: From source node to destination node
• Properties: Attributes on the relationship itself

# Python API
alice = db.create_node(['Person', 'Employee'],
                       name='Alice',
                       age=30,
                       skills=['Python', 'ML'])

bob = db.create_node(['Person'], name='Bob', age=25)

knows = db.create_relationship(alice, bob, 'KNOWS',
                               since=2020,
                               strength='strong')

# Cypher equivalent
db.execute("""
    CREATE (a:Person:Employee {name: 'Alice', age: 30, skills: ['Python', 'ML']})
    CREATE (b:Person {name: 'Bob', age: 25})
    CREATE (a)-[:KNOWS {since: 2020, strength: 'strong'}]->(b)
""")

Graph Patterns

GraphForge uses graph patterns for both matching and creating:

(n:Person)                          # Node with label
(n:Person {age: 30})               # Node with properties
(a)-[r:KNOWS]->(b)                 # Directed relationship
(a)-[r:KNOWS]-(b)                  # Undirected relationship
(a)-[:KNOWS|LIKES]->(b)            # Multiple relationship types

---

Python API Reference

GraphForge Class

__init__(path: str | Path | None = None)

Initialize a GraphForge instance.

Parameters:

• path (optional): Path to SQLite database file. If None, uses in-memory storage.

Example:

# In-memory (data lost on exit)
db = GraphForge()

# Persistent (data saved to disk)
db = GraphForge("graphs/social-network.db")

create_node(labels: list[str] | None = None, **properties) -> NodeRef

Create a node with labels and properties.

Parameters:

• labels: List of label strings (e.g., ['Person', 'Employee'])
• **properties: Property key-value pairs (str, int, float, bool, None, list, dict)

Returns: NodeRef for the created node

Example:

alice = db.create_node(
    ['Person', 'Employee'],
    name='Alice',
    age=30,
    active=True,
    skills=['Python', 'SQL'],
    metadata={'department': 'Engineering'}
)

create_relationship(src: NodeRef, dst: NodeRef, rel_type: str, **properties) -> EdgeRef

Create a directed relationship between two nodes.

Parameters:

• src: Source node (NodeRef)
• dst: Destination node (NodeRef)
• rel_type: Relationship type string (e.g., 'KNOWS', 'WORKS_AT')
• **properties: Property key-value pairs

Returns: EdgeRef for the created relationship

Example:

alice = db.create_node(['Person'], name='Alice')
company = db.create_node(['Company'], name='Acme Corp')

works_at = db.create_relationship(
    alice,
    company,
    'WORKS_AT',
    since=2020,
    role='Engineer'
)

execute(query: str) -> list[dict]

Execute an openCypher query.

Parameters:

• query: openCypher query string

Returns: List of result rows as dictionaries

Example:

results = db.execute("""
    MATCH (p:Person)-[r:KNOWS]->(friend:Person)
    WHERE p.age > 25
    RETURN p.name AS person, count(friend) AS friend_count
    ORDER BY friend_count DESC
    LIMIT 10
""")

for row in results:
    print(f"{row['person'].value}: {row['friend_count'].value} friends")

begin()

Start an explicit transaction.

Example:

db.begin()
db.execute("CREATE (n:Person {name: 'Alice'})")
db.commit()  # or db.rollback()

commit()

Commit the current transaction. Saves changes to disk if using persistence.

Raises: RuntimeError if not in a transaction

rollback()

Roll back the current transaction. Reverts all changes made since begin().

Raises: RuntimeError if not in a transaction

close()

Save graph and close database. Safe to call multiple times.

Example:

db = GraphForge("my-graph.db")
# ... make changes ...
db.close()  # Saves to disk

Accessing Result Values

Query results contain CypherValue objects. Access the underlying Python value with .value:

results = db.execute("MATCH (p:Person) RETURN p.name AS name, p.age AS age")

for row in results:
    name = row['name'].value      # str
    age = row['age'].value        # int
    print(f"{name} is {age} years old")

Supported Value Types:

• CypherString: Python str
• CypherInt: Python int
• CypherFloat: Python float
• CypherBool: Python bool
• CypherNull: Python None
• CypherList: Python list (nested CypherValues)
• CypherMap: Python dict (string keys, CypherValue values)

---

Cypher Query Language

GraphForge supports a subset of openCypher for declarative graph queries and mutations.

MATCH - Pattern Matching

Find nodes and relationships matching a pattern.

-- Match all nodes
MATCH (n)
RETURN n

-- Match nodes by label
MATCH (p:Person)
RETURN p.name

-- Match with multiple labels
MATCH (p:Person:Employee)
RETURN p

-- Match relationships
MATCH (a:Person)-[r:KNOWS]->(b:Person)
RETURN a.name, b.name, r.since

-- Match specific direction
MATCH (a)-[:FOLLOWS]->(b)    -- Outgoing
MATCH (a)<-[:FOLLOWS]-(b)    -- Incoming
MATCH (a)-[:FOLLOWS]-(b)     -- Either direction

-- Multiple relationship types
MATCH (a)-[r:KNOWS|LIKES]->(b)
RETURN type(r), a.name, b.name

WHERE - Filtering

Filter matched patterns with predicates.

-- Property comparisons
MATCH (p:Person)
WHERE p.age > 30
RETURN p.name

-- Logical operators
MATCH (p:Person)
WHERE p.age > 25 AND p.city = 'NYC'
RETURN p.name

MATCH (p:Person)
WHERE p.age < 30 OR p.active = true
RETURN p.name

-- Property existence (returns false for null)
MATCH (p:Person)
WHERE p.email <> null
RETURN p.name

RETURN - Projection

Select and transform query results.

-- Return specific properties
MATCH (p:Person)
RETURN p.name, p.age

-- With aliases
MATCH (p:Person)
RETURN p.name AS person_name, p.age AS person_age

-- Return entire nodes/relationships
MATCH (p:Person)-[r:KNOWS]->(friend)
RETURN p, r, friend

CREATE - Graph Construction

Create new nodes and relationships.

-- Create single node
CREATE (n:Person {name: 'Alice', age: 30})

-- Create multiple nodes
CREATE (a:Person {name: 'Alice'}), (b:Person {name: 'Bob'})

-- Create nodes with relationship
CREATE (a:Person {name: 'Alice'})-[r:KNOWS {since: 2020}]->(b:Person {name: 'Bob'})

-- Create with RETURN
CREATE (n:Person {name: 'Alice'})
RETURN n.name AS name

SET - Update Properties

Update properties on existing nodes and relationships.

-- Update single property
MATCH (p:Person {name: 'Alice'})
SET p.age = 31

-- Update multiple properties
MATCH (p:Person {name: 'Alice'})
SET p.age = 31, p.city = 'NYC', p.active = true

-- Update relationship properties
MATCH (a)-[r:KNOWS]->(b)
WHERE a.name = 'Alice'
SET r.strength = 'strong'

DELETE - Remove Elements

Delete nodes and relationships.

-- Delete specific node (and its relationships)
MATCH (p:Person {name: 'Alice'})
DELETE p

-- Delete relationship only
MATCH (a)-[r:KNOWS]->(b)
WHERE a.name = 'Alice' AND b.name = 'Bob'
DELETE r

-- Delete multiple elements
MATCH (a)-[r:KNOWS]->(b)
WHERE b.name = 'Bob'
DELETE r, b

MERGE - Idempotent Creation

Create nodes if they don't exist, or match existing ones.

-- Create or match
MERGE (p:Person {name: 'Alice'})

-- Always matches same node (idempotent)
MERGE (p:Person {name: 'Alice', age: 30})
MERGE (p:Person {name: 'Alice', age: 30})
-- Results in only 1 node

-- With RETURN
MERGE (p:Person {name: 'Alice'})
RETURN p.name

ORDER BY - Sorting

Sort query results.

-- Ascending (default)
MATCH (p:Person)
RETURN p.name, p.age
ORDER BY p.age

-- Descending
MATCH (p:Person)
RETURN p.name, p.age
ORDER BY p.age DESC

-- Multiple sort keys
MATCH (p:Person)
RETURN p.name, p.age, p.city
ORDER BY p.city ASC, p.age DESC

LIMIT and SKIP - Pagination

Limit and paginate results.

-- Get first 10 results
MATCH (p:Person)
RETURN p.name
ORDER BY p.name
LIMIT 10

-- Skip first 20, return next 10
MATCH (p:Person)
RETURN p.name
ORDER BY p.name
SKIP 20
LIMIT 10

Aggregations

Compute aggregate functions over groups.

-- Count all
MATCH (p:Person)
RETURN count(*) AS total

-- Count with grouping
MATCH (p:Person)
RETURN p.city, count(*) AS population
ORDER BY population DESC

-- Multiple aggregations
MATCH (p:Person)
RETURN
    count(*) AS total,
    sum(p.age) AS total_age,
    avg(p.age) AS avg_age,
    min(p.age) AS youngest,
    max(p.age) AS oldest

-- Aggregation with WHERE
MATCH (p:Person)
WHERE p.active = true
RETURN p.department, count(*) AS active_count

Supported Functions:

• count(*) - Count all rows
• count(expr) - Count non-null values
• sum(expr) - Sum numeric values
• avg(expr) - Average of numeric values
• min(expr) - Minimum value
• max(expr) - Maximum value

---

Usage Patterns

Pattern 1: Exploratory Analysis

Use in-memory graphs for quick exploration, then persist interesting results.

# Start with in-memory for speed
db = GraphForge()

# Load and explore data
db.execute("CREATE (:Author {name: 'Alice', h_index: 42})")
db.execute("CREATE (:Author {name: 'Bob', h_index: 38})")
# ... load more data ...

# Explore interactively
results = db.execute("""
    MATCH (a:Author)
    WHERE a.h_index > 40
    RETURN a.name, a.h_index
    ORDER BY a.h_index DESC
""")

# If analysis is valuable, save it
if len(results) > 0:
    db_persistent = GraphForge("high-impact-authors.db")
    # Copy relevant subgraph...
    db_persistent.close()

Pattern 2: Incremental Construction

Build graphs incrementally across sessions.

# Session 1: Initial data
db = GraphForge("knowledge-graph.db")
db.execute("CREATE (:Concept {name: 'Machine Learning'})")
db.close()

# Session 2: Add related concepts
db = GraphForge("knowledge-graph.db")
db.execute("""
    MATCH (ml:Concept {name: 'Machine Learning'})
    CREATE (dl:Concept {name: 'Deep Learning'})
    CREATE (ml)-[:SPECIALIZES_TO]->(dl)
""")
db.close()

# Session 3: Add more relationships
db = GraphForge("knowledge-graph.db")
db.execute("""
    MATCH (dl:Concept {name: 'Deep Learning'})
    CREATE (cv:Concept {name: 'Computer Vision'})
    CREATE (dl)-[:APPLIED_IN]->(cv)
""")
db.close()

Pattern 3: Transactional Updates

Use transactions for atomic updates.

db = GraphForge("production-graph.db")

try:
    db.begin()

    # Update multiple related entities
    db.execute("MATCH (p:Person {id: 123}) SET p.status = 'inactive'")
    db.execute("MATCH (p:Person {id: 123})-[r:WORKS_AT]->() DELETE r")
    db.execute("CREATE (:AuditLog {action: 'deactivate', user_id: 123, timestamp: 1234567890})")

    db.commit()
except Exception as e:
    db.rollback()
    print(f"Transaction failed: {e}")
finally:
    db.close()

Pattern 4: ETL Pipelines

Extract, transform, and load data into graph format.

import pandas as pd

# Load tabular data
papers = pd.read_csv("papers.csv")
citations = pd.read_csv("citations.csv")

# Transform to graph
db = GraphForge("citation-network.db")

# Create nodes from DataFrame
for _, row in papers.iterrows():
    db.execute("""
        CREATE (:Paper {
            id: $id,
            title: $title,
            year: $year,
            citations: $citations
        })
    """, {'id': row['id'], 'title': row['title'],
          'year': int(row['year']), 'citations': int(row['citation_count'])})

# Create relationships from edges DataFrame
for _, row in citations.iterrows():
    db.execute("""
        MATCH (citing:Paper {id: $citing_id})
        MATCH (cited:Paper {id: $cited_id})
        CREATE (citing)-[:CITES]->(cited)
    """, {'citing_id': row['citing_paper'], 'cited_id': row['cited_paper']})

db.close()

Pattern 5: Testing and Validation

Use transactions for isolated testing.

def test_graph_algorithm():
    db = GraphForge()

    # Setup test data
    db.execute("CREATE (a:Node {id: 1})-[:LINKS]->(b:Node {id: 2})")
    db.execute("CREATE (b)-[:LINKS]->(c:Node {id: 3})")

    # Test query
    results = db.execute("""
        MATCH path = (a:Node {id: 1})-[:LINKS*]->(c:Node)
        RETURN count(*) AS path_count
    """)

    assert results[0]['path_count'].value == 2

---

Examples

Example 1: Social Network Analysis

from graphforge import GraphForge

# Create social network
db = GraphForge("social-network.db")

# Add people
people = [
    ("Alice", 30, "NYC"),
    ("Bob", 25, "NYC"),
    ("Charlie", 35, "LA"),
    ("Diana", 28, "NYC"),
]

for name, age, city in people:
    db.execute(f"""
        CREATE (:Person {{name: '{name}', age: {age}, city: '{city}'}})
    """)

# Add friendships
friendships = [
    ("Alice", "Bob", 2015),
    ("Alice", "Charlie", 2018),
    ("Bob", "Diana", 2019),
    ("Charlie", "Diana", 2020),
]

for person1, person2, since in friendships:
    db.execute(f"""
        MATCH (a:Person {{name: '{person1}'}})
        MATCH (b:Person {{name: '{person2}'}})
        CREATE (a)-[:KNOWS {{since: {since}}}]->(b)
    """)

# Analysis: Who has the most friends?
results = db.execute("""
    MATCH (p:Person)-[:KNOWS]-(friend:Person)
    RETURN p.name AS person, count(DISTINCT friend) AS friend_count
    ORDER BY friend_count DESC
""")

print("Friend counts:")
for row in results:
    print(f"  {row['person'].value}: {row['friend_count'].value} friends")

# Analysis: People in NYC who know each other
results = db.execute("""
    MATCH (a:Person)-[:KNOWS]-(b:Person)
    WHERE a.city = 'NYC' AND b.city = 'NYC'
    RETURN DISTINCT a.name AS person1, b.name AS person2
""")

print("\nNYC connections:")
for row in results:
    print(f"  {row['person1'].value} ↔ {row['person2'].value}")

db.close()

Example 2: Document Citation Network

from graphforge import GraphForge

db = GraphForge("citations.db")

# Create papers
papers = [
    ("P1", "Graph Neural Networks", 2021, "Smith"),
    ("P2", "Deep Learning Fundamentals", 2019, "Jones"),
    ("P3", "GNN Applications", 2022, "Smith"),
]

for paper_id, title, year, author in papers:
    db.execute("""
        MERGE (p:Paper {id: $id})
        SET p.title = $title, p.year = $year
        MERGE (a:Author {name: $author})
        CREATE (a)-[:AUTHORED]->(p)
    """, {'id': paper_id, 'title': title, 'year': year, 'author': author})

# Add citations
db.execute("""
    MATCH (p1:Paper {id: 'P3'})
    MATCH (p2:Paper {id: 'P1'})
    CREATE (p1)-[:CITES]->(p2)
""")

db.execute("""
    MATCH (p1:Paper {id: 'P1'})
    MATCH (p2:Paper {id: 'P2'})
    CREATE (p1)-[:CITES]->(p2)
""")

# Find most cited papers
results = db.execute("""
    MATCH (p:Paper)<-[:CITES]-(citing:Paper)
    RETURN p.title AS paper, count(citing) AS citation_count
    ORDER BY citation_count DESC
""")

print("Most cited papers:")
for row in results:
    print(f"  {row['paper'].value}: {row['citation_count'].value} citations")

# Find papers by prolific authors
results = db.execute("""
    MATCH (a:Author)-[:AUTHORED]->(p:Paper)
    RETURN a.name AS author, count(p) AS paper_count
    ORDER BY paper_count DESC
""")

print("\nAuthor productivity:")
for row in results:
    print(f"  {row['author'].value}: {row['paper_count'].value} papers")

db.close()

Example 3: Knowledge Graph from LLM Output

from graphforge import GraphForge
import json

db = GraphForge("knowledge-graph.db")

# Simulated LLM extraction result
llm_output = {
    "entities": [
        {"name": "Python", "type": "Language", "properties": {"paradigm": "multi"}},
        {"name": "Java", "type": "Language", "properties": {"paradigm": "OOP"}},
        {"name": "Django", "type": "Framework", "properties": {"category": "web"}},
    ],
    "relationships": [
        {"source": "Django", "target": "Python", "type": "WRITTEN_IN"},
        {"source": "Python", "target": "Java", "type": "INFLUENCED_BY"},
    ]
}

# Import entities
for entity in llm_output["entities"]:
    props_str = ", ".join([f"{k}: '{v}'" for k, v in entity["properties"].items()])
    db.execute(f"""
        CREATE (:{entity['type']} {{name: '{entity['name']}', {props_str}}})
    """)

# Import relationships
for rel in llm_output["relationships"]:
    db.execute(f"""
        MATCH (source {{name: '{rel['source']}'}})
        MATCH (target {{name: '{rel['target']}'}})
        CREATE (source)-[:{rel['type']}]->(target)
    """)

# Query the knowledge graph
results = db.execute("""
    MATCH (f:Framework)-[:WRITTEN_IN]->(l:Language)
    RETURN f.name AS framework, l.name AS language
""")

print("Frameworks and their languages:")
for row in results:
    print(f"  {row['framework'].value} is written in {row['language'].value}")

# Find influence chains
results = db.execute("""
    MATCH (a:Language)-[:INFLUENCED_BY]->(b:Language)
    RETURN a.name AS language, b.name AS influenced_by
""")

print("\nLanguage influences:")
for row in results:
    print(f"  {row['language'].value} was influenced by {row['influenced_by'].value}")

db.close()

---

Advanced Features

Transaction Isolation

Transactions provide snapshot isolation—queries within a transaction see uncommitted changes.

db = GraphForge("test.db")

db.execute("CREATE (:Person {name: 'Alice'})")

db.begin()
db.execute("CREATE (:Person {name: 'Bob'})")

# Query sees uncommitted Bob
results = db.execute("MATCH (p:Person) RETURN count(*) AS count")
print(results[0]['count'].value)  # 2

db.rollback()

# After rollback, Bob is gone
results = db.execute("MATCH (p:Person) RETURN count(*) AS count")
print(results[0]['count'].value)  # 1

Deep Property Access

Access nested properties in complex structures.

db.execute("""
    CREATE (:Document {
        metadata: {
            author: 'Alice',
            tags: ['ML', 'Python'],
            version: {major: 1, minor: 2}
        }
    })
""")

results = db.execute("""
    MATCH (d:Document)
    RETURN d.metadata AS metadata
""")

metadata = results[0]['metadata'].value
print(metadata['author'].value)              # 'Alice'
print(metadata['tags'].value[0].value)      # 'ML'
print(metadata['version'].value['major'].value)  # 1

Graph Export

Export subgraphs for sharing or archival.

def export_subgraph(db, query, output_file):
    """Export query results to JSON."""
    results = db.execute(query)

    nodes = set()
    edges = []

    for row in results:
        # Extract nodes and relationships from result
        # (Implementation depends on your export format)
        pass

    with open(output_file, 'w') as f:
        json.dump({'nodes': list(nodes), 'edges': edges}, f)

# Export high-impact authors
export_subgraph(
    db,
    "MATCH (a:Author) WHERE a.h_index > 40 RETURN a",
    "high-impact-authors.json"
)

---

Design Principles

Spec-Driven Correctness

GraphForge prioritizes semantic correctness over raw performance. All query behavior is validated against the openCypher TCK (Technology Compatibility Kit).

What this means:

• Queries behave predictably and correctly
• Null handling follows openCypher semantics
• Aggregations produce deterministic results
• Type coercion is explicit and safe

Deterministic & Reproducible

GraphForge produces stable, reproducible results across runs.

What this means:

• Same query on same data always produces same results
• Transaction isolation guarantees snapshot consistency
• No hidden state or random behavior
• Ideal for scientific workflows and testing

Inspectable

GraphForge makes query execution observable and debuggable.

What this means:

• Query plans can be inspected (future feature)
• Storage layout is simple SQLite (readable with any SQLite tool)
• Execution behavior is predictable and traceable
• No magic or hidden optimizations

Replaceable Internals

GraphForge components are modular and replaceable.

What this means:

• Parser, planner, executor, storage are independent
• SQLite backend can be swapped for other storage
• Minimal operational dependencies
• Zero configuration required

---

Architecture

GraphForge is built in four layers:

┌─────────────────────────────────┐
│  Parser (Lark + AST)            │  Cypher → Abstract Syntax Tree
├─────────────────────────────────┤
│  Planner (Logical Operators)    │  AST → Logical Plan
├─────────────────────────────────┤
│  Executor (Pipeline Engine)     │  Plan → Results
├─────────────────────────────────┤
│  Storage (Graph + SQLite)       │  In-Memory + Persistence
└─────────────────────────────────┘

Parser: Lark-based openCypher parser with full AST generation Planner: Logical plan generation (ScanNodes, ExpandEdges, Filter, Project, Sort, Aggregate) Executor: Pipeline-based query execution with streaming rows Storage: Dual-mode storage—in-memory graphs with optional SQLite persistence

Storage Backend

GraphForge uses SQLite with Write-Ahead Logging (WAL) for durability:

• ACID guarantees: Atomicity, Consistency, Isolation, Durability
• Zero configuration: No server setup or connection management
• Single-file databases: Easy to version control and share
• Concurrent reads: Multiple readers, single writer
• MessagePack serialization: Efficient binary encoding for complex types

The architecture prioritizes correctness and developer experience over raw performance, with all components designed to be testable, inspectable, and replaceable.

---

Performance Characteristics

GraphForge is optimized for interactive analysis on small-to-medium graphs (thousands to millions of nodes).

Expected Performance:

• Node/edge creation: ~10-50K operations/sec (in-memory)
• Simple traversals: ~100K-1M edges/sec
• Complex queries: Depends on query complexity and graph size
• Persistence overhead: ~2-5x slower than in-memory

When to Use GraphForge:

• Graphs with < 10M nodes
• Interactive analysis in notebooks
• Iterative graph construction
• Research and exploration workflows

When NOT to Use GraphForge:

• Production applications requiring high throughput
• Graphs with > 100M nodes
• Real-time query serving
• Multi-user concurrent writes

For production workloads, consider Neo4j, Memgraph, or other production graph databases.

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Roadmap

Completed (v0.1):

• ✅ MATCH, WHERE, RETURN, ORDER BY, LIMIT, SKIP
• ✅ Aggregations (COUNT, SUM, AVG, MIN, MAX)
• ✅ CREATE, SET, DELETE, MERGE clauses
• ✅ Python builder API
• ✅ SQLite persistence
• ✅ ACID transactions

Planned (v0.2):

• MATCH-CREATE combinations (connecting existing nodes)
• DETACH DELETE (cascading relationship deletion)
• Path expressions and variable-length patterns
• UNWIND for list processing
• CASE expressions

Future Considerations:

• Query plan visualization
• Performance profiling tools
• Import/export to standard formats (GraphML, CSV)
• Integration with popular data science libraries
• Pydantic schema validation

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Contributing

GraphForge is in active development. Contributions are welcome!

Areas for Contribution:

• Additional Cypher features
• Performance optimizations
• Documentation and examples
• Bug reports and fixes
• Integration with data science tools

See CONTRIBUTING.md for guidelines.

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Documentation

• Quick Start Tutorial — Step-by-step guide for new users
• API Reference — Complete Python API documentation
• Cypher Language Guide — openCypher subset reference
• Architecture Overview — System design and internals
• Requirements Document — Full scope and design rationale

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Testing

GraphForge has 368 tests covering:

• Unit tests for parser, planner, executor, storage
• Integration tests for end-to-end workflows
• openCypher TCK compliance tests (17 passing)

Run the test suite:

# Install dev dependencies
uv sync --dev

# Run all tests
pytest

# Run with coverage
pytest --cov=graphforge --cov-report=html

# Run specific test categories
pytest -m unit           # Unit tests only
pytest -m integration    # Integration tests only
pytest -m tck            # TCK compliance tests

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FAQ

Q: How does GraphForge differ from NetworkX? A: GraphForge adds declarative querying (openCypher), automatic persistence (SQLite), and ACID transactions. NetworkX is great for algorithms; GraphForge is great for data management.

Q: Can I use GraphForge in production? A: GraphForge is designed for research and analysis, not production applications. For production workloads, use Neo4j or Memgraph.

Q: Does GraphForge support distributed queries? A: No. GraphForge is embedded and single-node only.

Q: Can I import data from Neo4j? A: Not directly yet. You can export from Neo4j to CSV and import via Python scripts.

Q: What's the maximum graph size? A: Practical limit is ~10M nodes. Beyond that, query performance degrades significantly.

Q: Is GraphForge thread-safe? A: No. Use one GraphForge instance per thread, or use external synchronization.

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License

MIT © David Spencer

GraphForge is open source software released under the MIT License. See LICENSE for details.

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Acknowledgments

GraphForge is built on excellent open-source projects:

• Lark — Fast, modern parsing library
• Pydantic — Data validation and settings management
• MessagePack — Efficient binary serialization
• openCypher — Declarative graph query language

Special thanks to the openCypher community for the TCK suite and language specification.

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Happy Graph Forging! 🔨📊