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Matching lessons: 33 / 33
Bitcoin for Savers · The basics · 1
What money is, and why Bitcoin exists
From the savings tin to M-Pesa to Bitcoin: what makes money work, and the problem Bitcoin was built to solve.
12 minBeginnerReadingQuiz
Bitcoin for Savers · The basics · 2
Sats, prices and volatility: saving in Bitcoin vs shillings
You don't need a whole bitcoin. Learn what sats are, why the price moves so much, and the questions to ask before saving in Bitcoin.
12 minBeginnerReadingQuiz
Bitcoin for Savers · Wallets and keys · 3
Wallets, keys and seed phrases
A wallet doesn't hold coins; it holds keys. Learn what you can share, what you must never share, and how to back up your seed phrase.
15 minBeginnerReadingQuiz
Bitcoin for Savers · Wallets and keys · 4
Self-custody vs custodial vs Fedimint ecash
Who holds the keys? Compare holding them yourself, letting a company hold them, and a community federation that holds them together.
15 minBeginnerReadingQuiz
Bitcoin for Savers · Using it safely · 5
Lightning payments: sending and receiving sats
Fast, cheap payments for everyday amounts. Learn how invoices work, how to receive and send, and what to check before you pay.
12 minBeginnerReadingQuiz
Bitcoin for Savers · Using it safely · 6
Scams and how to spot them
The tricks scammers use around Bitcoin, the red flags that give them away, and what to do if you or your chama are targeted.
15 minBeginnerReadingQuiz
Bitcoin for Savers · Together · 7
Saving together: chamas and group savings with Bitsacco
Chamas already know how to save together. Learn what changes when a group saves in sats, and the rules to agree on before the first contribution.
15 minBeginnerReadingQuiz
Bitcoin for Savers · Together · 8
Next steps: books, the whitepaper and community
You've finished the savers path. Here is where to read further, how to teach others, and how to help Jifunze grow.
10 minBeginnerReadingQuiz
Bitcoin for Builders · Lab · 1
Developer environment and a local regtest lab
Run a private Bitcoin network on your own computer, mine blocks on demand, and fund a test wallet in minutes.
45 minBeginnerReadingQuiz
Bitcoin for Builders · Protocol · 2
UTXOs and transactions
Bitcoin has no account balances. Learn the UTXO model, build a payment with change, and read a transaction field by field on regtest.
45 minBeginnerReadingQuiz
Bitcoin for Builders · Protocol · 3
Keys, addresses and descriptors
From a secret number to a bc1 address: how keys, HD wallets and output descriptors fit together, explored with your regtest wallet.
45 minBeginnerReadingQuiz
Bitcoin for Builders · Lightning and Fedimint · 4
Lightning: channels, invoices and routing basics
How two Bitcoin transactions can carry thousands of payments: channels, BOLT11 invoices, routing and liquidity, with a local Polar network.
60 minIntermediateReadingQuiz
Bitcoin for Builders · Lightning and Fedimint · 5
Fedimint: federations, ecash and guardians
How a group of guardians can hold bitcoin together and issue private ecash, and where Lightning gateways fit in.
45 minIntermediateReadingQuiz
Bitcoin for Builders · Build and contribute · 6
Building a Bitsacco mini-app
Build a small, mobile-first Lightning tip jar that turns a Lightning Address into an invoice, tested against a mock server with no real money.
90 minIntermediateReadingQuiz
Bitcoin for Builders · Build and contribute · 7
Contributing to Bitsacco open source
From finding an issue to a merged pull request: the workflow, the etiquette and the checks, practised on Bitsacco's own repositories, including this one.
60 minIntermediateReadingQuiz
Bitcoin for Builders · Build and contribute · 8
Project: ship a small Lightning or Fedimint tool
Your capstone. Pick a brief, build it on regtest or a mock, publish it as open source, and get it reviewed by the Bitsacco community.
600 minIntermediateReadingQuiz
Lightning for Builders · Foundations · 1
Introduction: why the Lightning Network exists
Bitcoin settles; Lightning moves. What problem Lightning solves, how it keeps Bitcoin's trust model, and what it costs you in return.
15 minBeginnerReadingQuiz
Lightning for Builders · Foundations · 2
Getting started: your lab and your first payment
Start the four-node lab on your laptop, connect it to this page, and make Dina's first invoice and Alice's first payment.
40 minBeginnerReadingQuizLab
Lightning for Builders · Foundations · 3
How the Lightning Network works
Open a channel yourself, confirm it on-chain, and pay through it, to see the three moves every channel makes: open, update, close.
45 minBeginnerReadingQuizLab
Lightning for Builders · Nodes · 4
Lightning node software
LND, c-lightning and Eclair all speak the same protocol but feel different to use. Ask all three the same question.
30 minIntermediateReadingQuizLab
Lightning for Builders · Nodes · 5
Operating a Lightning Network node
Running a node is a job: set the fees you charge for routing, back up your channels, and know what to watch.
35 minIntermediateReadingQuizLab
Lightning for Builders · Inside Lightning · 6
Lightning Network architecture
A map of the whole protocol, layer by layer, so every later lesson has a place to fit.
20 minIntermediateReadingQuiz
Lightning for Builders · Inside Lightning · 7
Payment channels
Look inside a real channel: find its funding transaction on-chain and see how commitment transactions and revocation keep both sides honest.
40 minIntermediateReadingQuizLab
Lightning for Builders · Inside Lightning · 8
Routing on a network of payment channels
How Alice pays Dina through two strangers without trusting either: hash time-locked contracts, step by step, then a real two-hop payment.
45 minIntermediateReadingQuizLab
Lightning for Builders · Inside Lightning · 9
Channel operation and payment forwarding
Two ways to end a channel: a cooperative close that settles at once, and a force close where the time lock makes you wait. Do both.
40 minIntermediateReadingQuizLab
Lightning for Builders · The network · 10
Onion routing
How each node on a route learns only its neighbours: build and peel a toy onion in Python, then compare it with the real Sphinx format.
45 minIntermediateReadingQuizLab
Lightning for Builders · The network · 11
Gossip and the channel graph
How every node learns the map of the network from its peers, and what that map contains. Read Alice's graph in Python.
35 minIntermediateReadingQuizLab
Lightning for Builders · The network · 12
Pathfinding and payment delivery
Write your own route finder over Alice's real channel graph, then see why real nodes also learn from failed attempts and split large payments.
50 minIntermediateReadingQuizLab
Lightning for Builders · Protocol · 13
Wire protocol: framing and extensibility
What a Lightning message looks like as bytes, how TLV fields let the protocol grow, and why feature bits follow the 'it's OK to be odd' rule. Parse a real init message.
40 minIntermediateReadingQuizLab
Lightning for Builders · Protocol · 14
Lightning's encrypted message transport
Every peer link is encrypted and authenticated with the Noise protocol before a single Lightning message flows. What the handshake does, and what your node's connections look like.
25 minIntermediateReadingQuizLab
Lightning for Builders · Protocol · 15
Lightning payment requests
Take an invoice apart: the human-readable part that holds the amount, the tagged fields inside, and the signature. Write a decoder for the amount.
35 minIntermediateReadingQuizLab
Lightning for Builders · Security and next steps · 16
Security and privacy of the Lightning Network
What an attacker can learn or break: probe a route's hidden balance yourself, then survey jamming, fee attacks and the defences.
45 minIntermediateReadingQuizLab
Lightning for Builders · Security and next steps · 17
Conclusion: what to build next
You have run every layer of Lightning yourself. Where the protocol is heading, and how to turn what you learned into a tool people use.
15 minIntermediateReadingQuiz