panproto 0.15.0

Universal schema migration engine (Python SDK)

panproto

Native Python bindings for panproto, a schema migration engine grounded in generalized algebraic theories. Built with PyO3 for zero-overhead access to the Rust core.

Requires Python 3.13+.

Installation

pip install panproto

Quick start

import panproto as pp

# List all 76+ built-in protocols
protocols = pp.list_builtin_protocols()

# Build a schema using the fluent builder
builder = pp.SchemaBuilder("atproto")
builder.vertex("post", "record", nsid="app.bsky.feed.post")
builder.vertex("post:body", "object")
builder.vertex("post:body.text", "string")
builder.edge("post", "post:body", "record-schema")
builder.edge("post:body", "post:body.text", "prop", name="text")
builder.constraint("post:body.text", "maxLength", "3000")
old_schema = builder.build()

# Auto-generate a lens between two schema versions
lens = pp.auto_generate_lens(old_schema, new_schema, protocol)
view, complement = lens.get(instance)
restored = lens.put(view, complement)

# Diff two schemas and classify changes
diff = pp.diff_schemas(old_schema, new_schema)
report = pp.diff_and_classify(old_schema, new_schema, protocol)

# Build and compile migrations
mig_builder = pp.MigrationBuilder()
mig_builder.map_vertex("post:body.text", "post:body.content")
migration = mig_builder.build()
compiled = pp.compile_migration(old_schema, new_schema, migration)

# Parse and emit data across protocols
io = pp.IoRegistry()
schema = io.parse_schema("json-schema", json_schema_str)
output = io.emit_schema("json-schema", schema)

# GAT operations
theory = pp.create_theory("MyTheory", sorts, operations, equations)
colimit = pp.colimit_theories(theory_a, theory_b, shared)

# Schematic version control
repo = pp.VcsRepository.init("/path/to/repo")
repo.add(schema)
repo.commit("add post schema", "author")

API overview

Schema and protocols

Function / Class	Description
list_builtin_protocols()	List all 76+ built-in protocol names
get_builtin_protocol(name)	Get a protocol definition by name
define_protocol(...)	Define a custom protocol
SchemaBuilder(protocol)	Fluent schema construction (vertex, edge, constraint, hyper_edge)
Schema	Immutable schema with vertex/edge/constraint access
Protocol	Protocol definition with edge rules and feature flags

Migration and lenses

Function / Class	Description
auto_generate_lens(src, tgt, protocol)	Auto-generate a bidirectional lens between schemas
Lens	Lens with get(instance) and put(view, complement)
Complement	Data discarded during get, needed by put
MigrationBuilder	Build migrations with vertex/edge mappings
compile_migration(src, tgt, migration)	Compile a migration for application
compose_migrations(m1, m2)	Compose two migrations sequentially
check_existence(src, tgt, migration, protocol)	Validate migration existence conditions

Breaking change detection

Function / Class	Description
diff_schemas(old, new)	Structural diff between two schemas
diff_and_classify(old, new, protocol)	Diff with breaking/non-breaking classification
SchemaDiff	Diff result with added/removed/changed elements
CompatReport	Compatibility report with breaking change details

Instance I/O

Function / Class	Description
Instance	W-type instance with from_json, to_json, validate
IoRegistry	Parse/emit schemas and instances across all protocols

GAT engine

Function / Class	Description
create_theory(name, sorts, ops, eqs)	Create a GAT theory
Theory	Theory with sort/operation/equation access
colimit_theories(t1, t2, shared)	Compute theory pushout
check_morphism(morphism, domain, codomain)	Verify a theory morphism
Model	Model of a theory with carrier sets

Version control

Function / Class	Description
VcsRepository.init(path)	Initialize a panproto repository
VcsRepository.open(path)	Open an existing repository
repo.add(schema)	Stage a schema
repo.commit(message, author)	Create a commit
repo.branch(name)	Create a branch
repo.merge(branch, author)	Merge a branch

Documentation

Full documentation at panproto.dev.

License

MIT