Compatibility

rLightning targets full compatibility with Redis 7.x. It implements the complete Redis Serialization Protocol (RESP2 and RESP3) and supports 400+ commands across all data types.

Protocol Support

RESP2 — Full support for the classic Redis protocol
RESP3 — Full support including HELLO negotiation, typed responses (Map, Set, Double, Null, Boolean, Push), and per-connection protocol version tracking
Inline commands — Supported for compatibility with telnet and simple clients

Command Coverage

rLightning implements 400+ Redis commands spanning every command category:

Strings — GET, SET, MGET, MSET, INCR, APPEND, GETRANGE, SETRANGE, and more
Hashes — HGET, HSET, HMGET, HMSET, HGETALL, HINCRBY, HSCAN, and more
Lists — LPUSH, RPUSH, LPOP, RPOP, LRANGE, LINDEX, LINSERT, BLPOP, BRPOP, and more
Sets — SADD, SREM, SMEMBERS, SINTER, SUNION, SDIFF, SSCAN, and more
Sorted Sets — ZADD, ZRANGE, ZRANGEBYSCORE, ZRANK, ZINCRBY, ZSCAN, and more
Streams — XADD, XREAD, XRANGE, XLEN, XGROUP, XACK, XCLAIM, and more
Bitmap — SETBIT, GETBIT, BITCOUNT, BITOP, BITFIELD, BITPOS
HyperLogLog — PFADD, PFCOUNT, PFMERGE
Geospatial — GEOADD, GEODIST, GEOHASH, GEOPOS, GEOSEARCH, GEOSEARCHSTORE
Transactions — MULTI, EXEC, DISCARD, WATCH, UNWATCH
Pub/Sub — SUBSCRIBE, PUBLISH, PSUBSCRIBE, SSUBSCRIBE, SPUBLISH
Scripting — EVAL, EVALSHA, SCRIPT, FUNCTION LOAD, FCALL
ACL — ACL SETUSER, ACL GETUSER, ACL LIST, ACL DELUSER, ACL LOG
Server — INFO, CONFIG, DBSIZE, FLUSHDB, FLUSHALL, CLIENT, COMMAND, and more
Cluster — CLUSTER INFO, CLUSTER NODES, CLUSTER SLOTS, CLUSTER MEET, and more
Sentinel — SENTINEL MASTERS, SENTINEL MONITOR, SENTINEL FAILOVER, and more

Known Incompatibilities

As of v2.0.0, there are no known incompatibilities between rLightning and Redis 7.x. All previously identified behavioral differences have been resolved.

Previously Resolved Issues

The following incompatibilities were identified through the multi-language compatibility test suite and have since been fixed:

GEOHASH accuracy — Geohash string precision now matches Redis 7.x output exactly
Pipeline error isolation — Per-command errors in a pipeline are captured as individual error responses instead of aborting the entire pipeline
CONFIG SET/GET — Runtime configuration changes and glob-pattern queries now match Redis behavior

Multi-Language Compatibility Testing

rLightning includes a comprehensive compatibility test suite that validates behavior against a real Redis 7 server using three major client libraries.

Client Libraries Tested

Language	Client Library	Version
Go	go-redis/v9	Latest
JavaScript	ioredis	Latest
Python	redis-py	Latest

Test Coverage

Each language implements approximately 231 tests across 25 categories:

Connection & Auth
Strings
Hashes
Lists
Sets
Sorted Sets
Key Management
Transactions
Pub/Sub
Pipelining
Lua Scripting
Lua Scripting Advanced
Streams
Streams Advanced
Advanced Types (Bitmap/HLL/Geo)
Edge Cases
Server Commands
ACL & Security
Blocking Commands
Memory Management & Eviction
Persistence (RDB/AOF)
Replication
Cluster Mode
Sentinel
Language-Specific (Go/JS/Python)

Running Compatibility Tests

The test suite runs each client against both Redis 7 and rLightning, then compares the results.

# Run the full suite in local mode (uses local Go/Node/Python, Docker for servers)
cd tests/docker-compat && ./run-tests.sh --local

# Run the full suite with Docker clients
cd tests/docker-compat && ./run-tests.sh

# Run an individual client against a specific server
REDIS_HOST=localhost REDIS_PORT=6379 REDIS_PASSWORD=test_password \
  go run ./tests/docker-compat/go-client/...

REDIS_HOST=localhost REDIS_PORT=6379 REDIS_PASSWORD=test_password \
  node tests/docker-compat/js-client/index.js

REDIS_HOST=localhost REDIS_PORT=6379 REDIS_PASSWORD=test_password \
  python tests/docker-compat/python-client/test_compat.py

# Generate a comparison report from collected results
python tests/docker-compat/report/generate-report.py --results-dir tests/docker-compat/results/

Test Methodology

A Redis 7 container and an rLightning container are started with identical configurations
Each client library runs its full test suite against both servers
Results are collected in JSON format
A comparison report highlights any behavioral differences
Containers are cleaned up automatically after the run

For the current list of known behavioral differences (if any), see tests/docker-compat/KNOWN-INCOMPATIBILITIES.txt in the repository.