Dragonfly

Dragonfly is an open-source, fully Redis- and Memcached-compatible in-memory data store built around a shared-nothing, vertically scalable architecture. We rate it 89/100 — for teams that have outgrown a single-threaded Redis node but don't want the operational tax of Redis Cluster, Dragonfly is the most credible drop-in replacement on the market.

What is Dragonfly?

Dragonfly is a modern in-memory datastore released in May 2022 by co-founders Roman Gershman (CTO) and Oded Poncz (CEO), former engineers from Google and AWS ElastiCache. The company hit general availability with Dragonfly 1.0 in March 2023 alongside a $21M seed and Series A led by Redpoint and Quiet Capital. As of May 2026, the GitHub project sits at 30,400+ stars, with the latest stable release v1.38.1 shipping on April 28, 2026.

The core problem Dragonfly attacks is that Redis is single-threaded by design. To scale Redis past one CPU core you either run multiple processes per box (and manage sharding yourself) or adopt Redis Cluster, which fragments your keyspace and breaks multi-key operations. Dragonfly rewrites the engine on top of a shared-nothing thread-per-core architecture and a novel hashtable (the Dash table), so a single node uses every CPU on the machine while keeping the wire protocol and command set compatible with Redis 7.x and Memcached.

Key Features of Dragonfly

• 25× higher throughput vs Redis on the same box: Dragonfly's published benchmark on a c6gn.16xlarge AWS instance reaches 3.8M QPS in standard mode and 15M QPS on GET in pipelined mode, versus a single Redis process bottlenecked on one core.
• Drop-in Redis & Memcached compatibility: Implements the RESP2/RESP3 protocols and the Memcached text protocol — clients, ORMs, and BullMQ-style queue libraries connect with no code changes.
• Up to 80% lower memory footprint: The Dash table and hashtable compaction routines shrink working-set memory significantly under mixed cache traffic, which translates directly into smaller (cheaper) instances.
• Vertical scaling without Redis Cluster: A single Dragonfly node saturates a 64-core machine; teams that previously needed a 6–12 node Redis Cluster can collapse to one or two nodes and keep multi-key transactions intact.
• Snapshotting that doesn't pause the world: Dragonfly's RDB-format snapshots use a point-in-time algorithm that doesn't fork, avoiding the latency spikes Redis users see during BGSAVE on large datasets.
• BSL 1.1 license: Source-available, free for the vast majority of users; restricts only commercial managed-service competitors. Self-hosting is unlimited and unrestricted.

What Users Say About Dragonfly

On Hacker News, the original Show HN drew significant praise for the engineering — multiple commenters with deep Redis backgrounds called the Dash-table design "genuinely novel" and the throughput numbers reproducible on their own hardware. On Reddit's r/devops and r/Database, the most-recommended use case is BullMQ and large hashmap workloads where users report Dragonfly handling 300+ GB and 500K ops/sec where managed Redis stalled. G2 reviewers in 2026 highlight "impressively fast performance" and "effortless migration from Redis," but two complaints recur: a few advanced Redis modules (notably RedisJSON and RediSearch with full feature parity) are still works in progress, and the minimum Cloud instance size feels large for hobby projects. The April 2024 "No Free Tier for You" post from Dragonfly itself acknowledged the hobby-tier gap and explained why dedicated RAM-backed compute makes a free forever tier impractical.

Dragonfly Pricing

Dragonfly itself is free to self-host under the BSL 1.1 license. Dragonfly Cloud is the company's fully managed offering and is billed by memory size and compute tier. New accounts get $100 of trial credit (no permanent free tier).

Plan	Starting Price	What You Get
Self-hosted (BSL 1.1)	Free	Unlimited size, run anywhere — Linux, Docker, Kubernetes
Cloud — Standard	~$11/month for 1 GB	Single-tenant managed instance, multi-AZ optional
Cloud — Enhanced	From ~$11/month for 1 GB Enhanced	Higher CPU per GB, faster pipelined throughput
Cloud — Extreme	Contact sales	Highest-throughput tier for billion-key workloads
Cloud trial	$100 credit	Applies to any tier; sufficient for several weeks of small-instance testing

Pricing scales linearly per GB and is also available on AWS Marketplace for committed-use discounts. There is no free forever tier — the company explicitly chose a $100 credit instead, citing the cost of always-on RAM-backed compute.

Who Should Use Dragonfly?

Best for: Backend and platform teams already running Redis at scale who are hitting single-core throughput ceilings, paying for oversized ElastiCache instances, or trying to avoid Redis Cluster's operational complexity. Especially strong for BullMQ/Sidekiq-style job queues, ML feature stores, session caches, and rate-limiting layers.

Not ideal for: Hobbyists and weekend projects who specifically need a $0 managed tier (use Upstash or self-host Valkey instead), or workloads that depend on the full RediSearch / RedisJSON / RedisTimeSeries module ecosystem at feature parity.

Pros and Cons

Pros:

• True drop-in compatibility — most teams migrate by changing the connection string and nothing else.
• Genuinely massive single-node throughput; collapses 6–12 node Redis Cluster setups into one box.
• Up to 80% memory savings reported under mixed cache workloads, which compounds into real infra savings.
• Active, transparent engineering team — Roman Gershman regularly posts deep-dive design notes.
• Source-available BSL 1.1 license is permissive for almost all production users.

Cons:

• No free tier on Dragonfly Cloud — only a $100 trial credit, which can frustrate hobby projects.
• BSL 1.1 is not OSI-approved; some procurement teams prefer pure Apache 2.0 (Valkey) or AGPL projects.
• Module ecosystem (RediSearch, RedisJSON, etc.) lags Redis Stack on advanced features.
• Smallest Cloud instance is larger than what hobbyists need; minimum spend is non-trivial.

Alternatives to Dragonfly

The closest direct competitors are Redis (the canonical original — battle-tested but single-threaded), Valkey (the Linux Foundation fork of Redis launched after the 2024 license change, fully Apache 2.0), KeyDB (multi-threaded Redis fork acquired by Snap), and Memcached for pure ephemeral caching. Of these, Valkey is the closest pure-OSS drop-in and Dragonfly is the closest performance-leader drop-in.

Verdict: Is Dragonfly Worth It?

If you are running Redis in production and the bill, the latency spikes during BGSAVE, or the headache of Redis Cluster have started to sting, Dragonfly is the easiest meaningful upgrade you can make this quarter. The 89/100 reflects best-in-class single-node throughput, real memory savings, and a pristine migration story — balanced against an immature module ecosystem versus Redis Stack and the lack of a free hobby tier on the managed Cloud product. For mid-sized SaaS, ML feature stores, and high-throughput queue backends, it's the recommendation. For hobby projects and casual side-builds, Valkey or self-hosted Dragonfly on a $5 VPS is the sensible path.

Frequently Asked Questions

Is Dragonfly free?

Yes — the Dragonfly server is free to self-host under the BSL 1.1 license. Dragonfly Cloud is paid (no permanent free tier), but new accounts get $100 of trial credit and Cloud instances start around $11/month for 1 GB.

Is Dragonfly a true drop-in replacement for Redis?

For the overwhelming majority of Redis 7.x commands, yes. Connection strings, RESP2/RESP3 protocol, eviction policies, transactions, Pub/Sub and streams all work without client changes. Some Redis Stack modules (RediSearch, RedisJSON) have partial feature parity.

What platforms does Dragonfly support?

Linux (x86_64 and ARM64) is the primary target, distributed as a static binary, official Docker image, Helm chart, and on AWS Marketplace. Dragonfly Cloud runs on AWS, GCP and Azure regions.

Is Dragonfly open source?

Source-available under the Business Source License 1.1 — free to use, modify and self-host for almost all purposes. The license restricts only competing managed services. The code is on GitHub.

How does Dragonfly compare to Valkey?

Valkey is the Linux Foundation Redis fork under Apache 2.0 — it stays single-threaded like Redis. Dragonfly is multi-threaded and shared-nothing, delivering significantly higher single-node throughput. Pick Valkey for OSI-pure licensing, pick Dragonfly for raw performance per dollar.