Helius charges $25,000/mo. We rebuilt it for $120.
getTransactionsForAddress is one of the most useful Solana RPC methods shipped in years. Feed it a wallet, get every transaction that touched it — direct calls, ATA balance changes, ALT-expanded accounts. It replaced the painful getSignaturesForAddress-plus-a-thousand-getTransaction-calls dance that every indexer had to write.
It’s also expensive. Helius prices it at 50 credits per call, or $0.00025 per request. For an app serving 100 million queries a month — a modest Jupiter-class workload — that’s $25,000 per month.
Meanwhile, the underlying data is completely public.
Old Faithful already hosts everything
Project Yellowstone’s Old Faithful is a free, open archive of every block Solana has ever produced — 464.6 TB of CAR files on a Cloudflare-backed CDN. Triton One and the Solana Foundation built it so anyone could stop paying BigTable rent for Solana history.
What Old Faithful doesn’t have is an address index. It maps slots to blocks and signatures to CIDs, but there’s no “wallet → paginated tx history” lookup matching what Helius sells.
That gap is filled by building a compact secondary index on top of OF.
The design
A single, well-scoped artifact:
- 256 compact R2 objects (
shard-NNN.bin), each containing sorted address → (slot, tx_index, car_start, car_size) rows, varint-encoded, zstd-compressed with a trained dictionary. - A jetstreamer plugin that streams Old Faithful CAR files, extracts all addresses per tx (including ALT-expanded keys and ATA owners), and emits shard files.
- A Rust query library (with a WASM build for browsers) that takes an address and returns paginated tx history. One R2 range read per page.
Total code: ~2,000 lines of Rust. The full-history Solana address index fits in ~8 TB on Cloudflare R2 and serves queries for $120/month flat.
Why so cheap?
Helius re-ingests and stores the entire chain (~1 PB compressed to 288 TB in their stack). Old Faithful already hosts all of that for free. We only need the index — the mapping from wallet to byte offsets in OF’s CAR files.
Every row is:
(address, slot, tx_index, car_start, car_size, err_flag, ref_type)Once you know the byte range, one HTTP range read against files.old-faithful.net gets you the transaction. No local CAR storage required.
The cost ladder
| Tier | Monthly cost | What you get |
|---|---|---|
| SolPack filtered on R2 | $735 | Compressed archive, no votes |
| Full stack with verification | $1,800 | PoH-verified, query-ready |
| Raw CAR files on R2 | $7,000 | Full Old Faithful mirror |
| Helius at 100M queries | $25,000 | Managed, full API surface |
For workloads above ~$5k/month in Helius spend, the self-hosted path makes financial sense. Below that, Helius is probably the right call — they did the engineering and they deserve to be paid for it.
Status
This is a design and benchmarking project seeking funding. Every number in this post comes from real measurements — sampled blocks, HEAD-requested CAR files, timed range reads against the public CDN. The benchmarks are reproducible.
If you’re interested in funding, running a mirror, or contributing, check the repo or get in touch.