Trade-offs

You made it to the last chapter. For eleven chapters we’ve been showing off Nostr’s tricks: keys you own, events anyone can verify, relays anyone can run. Now it’s time for the part sales brochures skip: what Nostr is bad at.

Think of Nostr like owning a house instead of renting an apartment. Nobody can kick you out, and you can paint the walls any color you like. But when the boiler breaks at 3 a.m., there’s no landlord to call. Every “pro” in this chapter comes with a matching “con”, and that’s not a bug: it’s the price of having no one in charge.

Spam: nobody’s guarding the door

On a big platform, a whole team (plus a lot of software) fights bots for you. On Nostr there’s no “the company”, so there’s no spam team. Creating a new identity costs nothing: generate a keypair and you’re in. That’s wonderful for a dissident and equally wonderful for a spammer who can make a million accounts per minute.

So Nostr fights spam in layers, and each relay and client picks its own mix:

• Make posting cost something. A relay can ask for proof-of-work (a little math puzzle per note) or money: a paid relay only accepts notes from people who paid a small fee.
• Know who’s talking. Relays can require a login handshake (NIP-42) before accepting notes.
• Trust your friends’ friends. A web of trust filter only lets through people your follows (or their follows) follow. Bots rarely get followed by real people, so they bounce off.

Let’s try the first one. Proof-of-work asks your device to find a note whose event id starts with a bunch of zeros. The only way to find one is trial and error: change a counter, re-hash, check, repeat. Each extra zero bit doubles the work. Crank up the difficulty and press “Start mining”:

Notice the trade-off in the last box? A note that costs you a blink costs a spammer sending ten thousand of them hours. But a spam farm with fast computers pays far less than your phone does, so proof-of-work is a speed bump, not a wall.

{
  "id": "000006d8c378af1779d2feebc7603a125d99eca0ccf1085959b307f64e5dd358",
  "pubkey": "a48380f4cfcc1ad5378294fcac36439770f9c878dd880ffa94bb74ea54a6f243",
  "created_at": 1651794653,
  "kind": 1,
  "tags": [["nonce", "776797", "20"]],
  "content": "It's just me mining my own business",
  "sig": "284622fc0a3f4f1303455d5175f7ba962a3300d136085b9566801bc2e0699de0c7e31e44c81fb40ad9049173742e904713c3594a1da0fc5d2382a25c11aba977"
}

import { finalizeEvent, generateSecretKey, getPublicKey } from "nostr-tools/pure";
import { getPow, minePow } from "nostr-tools/nip13";

const sk = generateSecretKey();
const unsigned = {
  kind: 1,
  created_at: Math.floor(Date.now() / 1000),
  tags: [],
  content: "gm",
  pubkey: getPublicKey(sk),
};
// Synchronous and CPU-heavy: run it in a Web Worker in real apps.
const mined = minePow(unsigned, 16);
console.log(getPow(mined.id)); // ≥ 16
const event = finalizeEvent(mined, sk); // id is unchanged by signing

Discovery: there’s no front page

Twitter-style apps have one giant database and an algorithm that decides what you see. Nostr has hundreds of relays, and none of them sees everything. That’s great for censorship resistance (no single off switch), but it makes some everyday things surprisingly hard:

• Search only covers the relays you ask, and only relays that support it.
• Finding people often happens by word of mouth, shared follow lists or a NIP-05 name.
• Counting likes or followers is a best guess: you can only count what your relays have.

The ecosystem patches this with search relays, aggregator relays that crawl many others, and custom feeds. They work, but they quietly re-introduce a few big players. Keep an eye on that.

Relay economics: someone pays for the servers

Relays are computers with electricity bills, bandwidth and disks that fill up with every note, image link and reaction. Running one costs real money, and on Nostr there are no ads to pay for it. So relays end up in a few buckets:

• Free relays run by enthusiasts or companies. Lovely, but they can rate-limit you, drop old notes to save space, or simply shut down when the volunteer moves on.
• Paid relays charge a one-time or monthly fee. Less spam, more stability, but now posting has a price tag.
• Your own relay, run at home or on a cheap server, so your notes have at least one home you control.

This is why the outbox model from chapter 7 matters so much: by publishing to several relays and advertising them in your relay list, no single relay’s budget decides whether your notes survive.

{
  "name": "relay.alpha.example",
  "limitation": {
    "payment_required": true,
    "auth_required": true,
    "min_pow_difficulty": 0,
    "restricted_writes": true
  },
  "payments_url": "https://relay.alpha.example/pay",
  "fees": {
    "admission": [{ "amount": 21000000, "unit": "msats" }],
    "subscription": [{ "amount": 5000000, "unit": "msats", "period": 2592000 }],
    "publication": [{ "kinds": [4], "amount": 100, "unit": "msats" }]
  }
}

import { fetchRelayInformation } from "nostr-tools/nip11";

const info = await fetchRelayInformation("wss://relay.alpha.example");
if (info.limitation?.payment_required) console.log("Pay here:", info.payments_url);

Moderation is a client choice

On X, one rulebook applies to everyone. On Mastodon, your server’s admin writes the rulebook. On Nostr, there’s no rulebook at all, just choices:

• A relay decides what it stores. It can refuse notes, ban pubkeys, or only serve paying members.
• Your client decides what it shows. It can hide words, apply your mute list, or respect reports from people you trust.
• You decide which relays and which client to use, and you can switch any time.

The good news: nobody can silence you everywhere. The less-good news: nobody will clean up your feed for you either, and a relay you’d never use can still host things you’d hate. “Free speech” on Nostr means “free to speak”, not “guaranteed an audience”.

{
  "kind": 10000,
  "tags": [
    ["p", "<spammer pubkey hex>"],
    ["t", "crypto-giveaway"],
    ["word", "airdrop"]
  ],
  "content": ""
}

Data availability: who keeps your notes?

Your notes live wherever relays decided to keep them. If you posted to one free relay and it wiped its database, those notes are gone. Nobody promised to keep them, and there’s no “Nostr archive” in the sky. The flip side: if you publish to several relays (or run your own), your notes are about as durable as it gets, because no single company can delete all the copies.

Key loss: no “forgot password” button

This is the big one. Your identity is your private key (your nsec). That’s what makes Nostr uncensorable, and it’s also what makes key loss brutal:

• Lose it and your account is gone. No email reset, no support ticket, no admin who can help. You make a new key and ask everyone to follow you again.
• Leak it and it’s even worse. The thief can post as you, forever, and relays can’t tell you apart: both of you make perfectly valid signatures. There’s still no standard way to rotate a key (swap it for a new one while keeping your followers); proposals exist, but none has been widely adopted.

So Nostr’s answer is: don’t lose it, and don’t let it leak. Back it up (on paper, or as an encrypted ncryptsec), and keep it inside a signer (chapter 10) so apps never see it.

import { generateSecretKey } from "nostr-tools/pure";
import { decrypt, encrypt } from "nostr-tools/nip49";

const sk = generateSecretKey();
const backup = encrypt(sk, "correct horse battery staple"); // "ncryptsec1…"
const restored = decrypt(backup, "correct horse battery staple"); // same bytes as sk

What could possibly go wrong?

Enough theory. Flip on a few bad days and see how each network copes. Then turn on some Nostr precautions and watch the red turn green (well, most of it).

See the pattern? Big platforms are great at recovering you (they hold the keys) and terrible at not banning you (they hold the keys). Nostr is the exact mirror image. Which one you want depends on which bad day scares you more.

The big comparison

Nostr isn’t the only project trying to fix social media. Mastodon (part of the federated “fediverse”) spreads accounts across thousands of independent servers. Bluesky uses the AT Protocol: portable accounts, but most people use infrastructure run by Bluesky itself. And X is the classic one-company platform.

There’s no winner, only trade-offs. Tick the things you care about and watch the ranking change:

Quick check

You did it!

From “why bother?” all the way to “what’s the catch?”. You can now explain keys, events, relays, filters, kinds, the social graph, private messages, zaps, signers, the ecosystem and its trade-offs. That’s a lot of nostrich knowledge.