awesome-python-patterns

Not a link list, and not idiom snippets — 99 runnable, run-gated, stdlib-only Python patterns.

Every file in this repository:

• runs — python3 patterns/<category>/<pattern>.py executes a working demo/self-test, standard library only, no pip install, no network;
• passed a run-gate — executed end-to-end, per-pattern, logged (see gate_logs/) before it was allowed in;
• is real implementation — data structures, distributed-systems machinery, resilience patterns — not toy pseudocode;
• ships with its own doc — every <pattern>.py has a <pattern>.md beside it: what it does, the guarantee its self-test actually asserts, and the checkable constraints, quoted from the code rather than described around it.

Quick start

git clone https://github.com/myfjin/awesome-python-patterns
cd awesome-python-patterns
python3 patterns/distributed/raft_consensus.py     # watch a Raft cluster elect a leader
python3 patterns/data_structures/red_black_tree.py # watch a red-black tree stay balanced
python3 tools/run_gate.py                          # run the whole gate yourself
cat patterns/data_structures/bloom_filter.md       # the doc that ships beside every pattern

The patterns

Data Structures (18)

Pattern	What it is	Doc
avl_tree	AVL Tree Implementation	md
binary_indexed_tree	Binary Indexed Tree	md
bloom_filter	Bloom Filter	md
fenwick_tree	Fenwick Tree (Binary Indexed Tree) implementation with comprehensive functionality.	md
interval_tree	Interval Tree	md
kd_tree	A complete k-d tree implementation for 2D points with insert, nearest neighbor,	md
merkle_tree	A simple Merkle tree implementation using SHA-256 hashing.	md
ordered_map	Ordered Map	md
persistent_deque	Persistent Deque	md
priority_task_scheduler	Priority Queue Scheduler Module	md
radix_tree	Radix Tree	md
red_black_tree	Red Black Tree	md
segment_tree	Segment Tree	md
skip_list	Skip List	md
suffix_array	Suffix Array	md
treap	Treap	md
trie	Trie (Prefix Tree) implementation with autocomplete functionality.	md
union_find	Union Find	md

Monitoring & Observability (12)

Pattern	What it is	Doc
alert_manager	Alert Manager	md
event_logger	Structured event logger with rotation capabilities.	md
log_pattern_matcher	Log Pattern Matcher	md
metric_aggregation_engine	Metric Aggregation Engine	md
metric_aggregator	Metric aggregator with tags for counters, gauges, and histograms.	md
metrics_formatter	Metrics Formatter	md
time_series_db	In-memory time-series database module with support for insertion, querying,	md
timer_stack	Timer Stack	md
trace_collector	Trace Collector	md
trace_sampler	Distributed Tracing Sampler Module	md
trace_span_collector	Distributed Tracing Span Collector Module	md
window_sampler	Anomaly Detection Sampler Module	md

Performance (11)

Pattern	What it is	Doc
batch_controller	Adaptive Batch Size Controller	md
budget_allocator	Request Collapser Module	md
free_list_allocator	Free List Allocator	md
hyperloglog	HyperLogLog probabilistic cardinality estimator implementation.	md
job_scheduler	A simple job scheduler with cron-like expressions.	md
lru_cache	Lru Cache	md
object_pool_allocator	Object Pool Allocator	md
resource_budget_allocator	Resource Budget Allocator Module	md
rw_lock	Rw Lock	md
token_bucket	Token Bucket	md
work_stealing_queue	Work-Stealing Queue Implementation	md

Distributed Systems (9)

Pattern	What it is	Doc
consistent_hash_ring	Consistent Hash Ring Implementation	md
crdt_sets	CRDT Sets Implementation	md
distributed_lock_manager	Distributed Lock Manager	md
g_counter_crdt	Distributed Counter Implementation	md
gossip_protocol	Gossip Protocol Membership List Implementation	md
quorum_consensus	Quorum consensus simulator module.	md
raft_consensus	Raft Consensus Algorithm Implementation	md
service_registry	Service Registry	md
vector_clock	Vector Clock implementation for detecting causal relationships between events	md

Networking (9)

Pattern	What it is	Doc
connection_pool	Connection Manager with Pooling	md
connection_pool_health_checks	Connection Pool with Health Checks Module	md
dns_cache	Dns Cache	md
http_retry_client	HTTP Client with Retry, Backoff, and Circuit Breaker Support	md
http_router	HTTP Request Multiplexer Module	md
packet_parser	Packet Parser	md
rate_limiter	Rate Limiter	md
rtt_estimator	Round-trip time estimator module with EWMA smoothing and timeout calculation.	md
url_router	Url Router	md

Algorithms & Reasoning (9)

Pattern	What it is	Doc
astar_pathfinding	A* Pathfinding Algorithm Implementation	md
bayesian_network	Bayesian Belief Network Implementation	md
csp_solver	Constraint Satisfaction Problem (CSP) Solver Module	md
decision_tree	Simple Decision Tree Classifier	md
dependency_graph	Dependency Graph Resolver - Topological Sort Implementation	md
expression_evaluator	Simple Expression Evaluator with Variables	md
minimax_game_search	A complete minimax game solver with alpha-beta pruning and depth limiting.	md
rule_engine	Rule-based inference engine with forward chaining and conflict resolution.	md
sat_solver	Sat Solver	md

I/O & Parsing (8)

Pattern	What it is	Doc
arg_parser	Arg Parser	md
chunked_reader	Line-delimited file parser with chunked reads.	md
csv_to_json	CSV to JSON converter module with type inference, nested key support, and streaming.	md
csv_validator	CSV Validator and Transformer Module	md
diff_engine	A simple diff engine for text comparison.	md
ini_parser	Simple INI file parser module.	md
log_parser	JSON Schema Validator Module	md
template_engine	Template Engine	md

Architecture (7)

Pattern	What it is	Doc
cqrs_bus	Simple CQRS Command/Query Splitter Module	md
event_bus	Event Bus with Typed Channels	md
event_sourcing_store	Event Sourcing Store Implementation	md
message_encoder	Message Format Encoder/Decoder Module	md
plugin_registry	Plugin registry with lazy loading, dependency management, and entry point discovery.	md
saga_coordinator	Saga Pattern Coordinator Module	md
state_machine	Simple State Machine Engine	md

Async & Concurrency (5)

Pattern	What it is	Doc
async_task_queue	Async Task Queue with Priority and Retries	md
cancellable_task_group	Async task group implementation with cancellation support.	md
priority_queue_scheduler	Priority Queue with Deadline Scheduling Module	md
pubsub_broker	A simple pub-sub message broker implementation with wildcard topic matching.	md
reactive_signals	Reactive Signals	md

Resilience (4)

Pattern	What it is	Doc
bulkhead_isolator	Bulkhead Pattern Isolator Module	md
circuit_breaker	Circuit Breaker	md
dead_letter_queue	Dead Letter Queue Handler Module	md
timeout_guard	Timeout Guard	md

Persistence (3)

Pattern	What it is	Doc
lsm_tree	LSM-Tree Engine Implementation	md
segmented_wal	Write-Ahead Log (WAL) implementation for durable transaction logging.	md
write_ahead_log	Write-Ahead Log (WAL) implementation for data durability and crash recovery.	md

Security (3)

Pattern	What it is	Doc
capability_access	Capability-Based Access Control System	md
hotp_totp	Time-Based One-Time Password (TOTP) generator and validator.	md
secure_envelope	Secure Envelope Module	md

Vision (1)

Pattern	What it is	Doc
image_stats	Histogram-based image contrast stretcher module.	md

Quality bar

"Run-gated" means: we do not claim a pattern works — we run it, on the commit that ships it, and keep the log. The gate script ships in this repo — one command lets you re-verify every claim yourself — and CI re-runs it on every push. If a pattern is listed here, it executed cleanly with a 90-second timeout on the day of the commit.

Two verification instruments (which one you're holding)

This free sample's verifier is tools/run_gate.py — it re-runs all 99 patterns in this repo and is the command to use here. The full AURA Pattern Library (1,024 patterns / 1,500 files across Python, C++, Go, Rust, R and JavaScript) has a second, library-wide instrument, tools/census.py, which sweeps every file for run-validity, real assertions, and determinism (3 runs, byte-identical output) and reconciles the counts against the signed catalog. census.py ships with the full library, not with this sample — if an email or doc pointed you at it, on this repo the equivalent command is python3 tools/run_gate.py. Full-library access (including census.py and its reproducible census results) is available on request.

Provenance — stated honestly

These patterns were machine-harvested from qwen3-coder:480b (Apache 2.0, via Ollama cloud), then human-curated: de-duplicated, categorized, policy-checked (stdlib-only), defect-fixed, and run-gated per file. MANIFEST.json maps every pattern to its harvest session, its checksum, and the checksum of its doc — all 198 hashes regenerated and verified against the files on 2026-08-07. We think the honest description of this collection is: AI-generated, human-verified.

C++ twins — available now

Every pattern in this repo has a modern C++17 twin — compiled and self-tested on macOS (ARM64) and Linux (x86-64), delivered side-by-side with its Python original, verification logs included. The free tier is this repo, complete, forever.

Get the C++ Twins → — $29, all 99 patterns, free updates for life.

License

MIT — see LICENSE.