Saving Satoshi
There’s never really been an easy, let alone fun, way to get people engaged with bitcoin tech. That was until Saving Satoshi, a light-hearted, interactive role-playing game (RPG) that functions as a first point of contact for coders learning bitcoin development.
Saving Satoshi uses storytelling and game mechanics to onboard curious developers into bitcoin tech and the ₿OSS (bitcoin open source software) ecosystem. With fun, innovative challenges, it’s designed to be a gentle and welcoming entry point for those wishing to go deeper into the world of bitcoin development. From address derivation to block template construction, players are introduced to a variety of technical topics over the course of ten chapters, each filled to the brim with challenges, simulations, and coding exercises. Beginning with basic concepts like hashing and using a block explorer, learners quickly advance to more difficult material that ultimately culminates in the lightning network.
Chapter 1 starts with learning how to look up transaction data in an explorer.
This unique learning experience is told as a sci-fi epic set in a hyperbitcoinized future. The year is 2139, and the entire bitcoin network has come to a halt. It is up to the player to figure out what is going on and to ultimately save bitcoin. Luckily assistance comes in the form of a holographic cat that delivers messages and clues from “Satoshi”. Despite her attitude, Holocat is surprisingly helpful and remains with the player throughout the course of the game. She can often be seen guiding users to technical learning exercises that are complemented by various aspects of bitcoin culture.
In chapter 3, players learn about 51% attacks.
The ambition
Bitcoin is serious, but learning about it doesn’t have to be. After looking around, we noticed there weren’t many projects that subscribed to this philosophy so we set out to build something that did.
Saving Satoshi strives to make technical bitcoin education more fun and accessible while complementing, not replacing, existing resources like books, podcasts, and courses. By adding a playful spin, projects like this can be a gentle and welcoming entry point for bitcoin tech. This is especially true for people where just the thought of bitcoin code comes with the emotional barriers of feeling overwhelmed and intimidated. Even better, this lighthearted approach allows us to integrate other elements we are passionate about like culture, design, and history to create a well rounded experience.
Learning doesn’t have to be boring. It can be joyful and entertaining. There is no reason why the bitcoin ecosystem can’t have beautiful, captivating educational products that touch on all the things that make bitcoin special. We believe learning about bitcoin can be just as creative, unique, and innovative as the technology itself.
Onboarding ₿OSS devs
We feel that bitcoin is a positive force in the world, and want to see more bitcoiners and bitcoin devs. Understanding it from a technical standpoint, even if it’s just the basics, is often the main step to deeper involvement. With more contributors, bitcoin can grow stronger, no matter what challenges it faces.
Personal reasons
This project is also driven by personal reasons. There is an enjoyment to be had from the creative challenge of putting something unique and innovative out into the world. Educators get to experiment and iterate on the developer learning experience. Designers get to play with storytelling and generative AI. Engineers get to uncover new or forgotten details about bitcoin tech.
Origin story
In October 2022, the Bitcoin Design Community organized its first Designathon, in collaboration with the first Bolt.fun Legends of Lightning hackathon. Adam Jonas of Chaincode Labs proposed the initial idea of Saving Satoshi, which was very close to what the project came to be. Take a look back in this recording of the first call the group had together.
Christoph, who helped organize the Designathon, simply meant to help get the project off the ground while Jonas was traveling for a few days. Little did he know that he would go on to lead the design for the next two+ years.
Several developers joined the project to evaluate various technical approaches and to start building the first prototypes and proof-of-concepts. This initial effort paid off, and the project won the award for Best Design in the Global Adoption Track.
Progress
Excited about the positive response, the team continued building. In December 2023, about a year later, the team reached the half-way point with the completion of the first five chapters. The submission video for the second Legends of Lightning hackathon is a good overview of the project at the time.
The Saving Satoshi workshop at TABConf 2024.
About a year later in October of 2024, as the final chapters were nearing completion, the first Saving Satoshi workshop was organized at TABConf in Atlanta, GA. It was a great excuse to get some of the team together, while also putting the game in front of players to collect live feedback.
Eager to get Saving Satoshi in front of more learners, the team wrapped up chapters nine and ten a few months later in December 2024 and the project was officially launched.
Team & contributions
Some of the team met at TABConf 2024.
There have been many contributors to the project over the course of its development. A small core team has provided continuity, and others have helped out in many different ways. Roughly speaking, there are five work groups:
1. Learning content
Bitcoin has no shortage of rabbit holes, and the game’s educational content reflects this. Players are exposed to a variety of bitcoin tech including:
- Finding and decoding the secret message in the genesis block
- Hash functions and proof-of-work
- The dynamics of pooled mining
- The basics of elliptic curve cryptography and how to derive an address from public-private key pairs
- ECDSA message signing and verification
- Building a transaction from scratch
- Assembling transactions to construct a block template
- Using the Bitcoin Core RPC API and calculating the block subsidy
- Bitcoin Script
- How the Lightning network works
Some subjects, like the basics of elliptic curve cryptography, can be difficult to understand with traditional forms of learning like books and white papers. Having said that, Saving Satoshi is not designed to compete with these resources, rather its goal is to complement them. It offers players yet another way to approach bitcoin tech, one with a higher level of interactivity and visuals, and where learning drives a story forward.
Working with a story
Players will find that the exercises they complete go hand in hand with the narrative. One example is in chapter five where the villain, Thomas Vanderpoole, claims to be the great-grandson of Satoshi Nakamoto. Users learn that if this claim is indeed true, Vanderpoole should have no problem producing a digital signature with one of Satoshi’s keys. The game guides the player through an adventure that begins with reading an old message from Hal Finney on the Bitcoin Talk forum. Then, that information is used to find one of Satoshi’s public keys in the blockchain. Following that, users dive into the specifics of the ECDSA message signing and verification algorithm used in Bitcoin Core before executing the code themselves to figure out if Vanderpoole is really telling the truth.
Learning history to build strong foundations
While some of the topics covered in Saving Satoshi involve concepts used less commonly today, it can be beneficial to understand how things got to where they are now. With simple, straightforward examples, players build solid foundations before layering on the complexity. In many cases, this is similar to the natural trajectory of whatever aspect of bitcoin technology a chapter happens to be focused on.
Take addresses that correspond to public keys as an example. While we now have more advanced address types that involve scripts and other elements of a transaction, you can still see P2WPKH, and even P2PKH addresses in block explorers, wallet software, and documentation. In Saving Satoshi, players first master public-private key cryptography and the corresponding address derivation for public keys before moving onto more advanced topics like bitcoin Script. Attempting to learn everything at once would be like drinking from a firehose.
Anonymous feedback collected by a player.
The bitcoin industry deliberately moves at a pace that is slow and steady. Many software projects do not use the latest and greatest technology until it has been battle tested. Even when the time comes for a product to move to a newer solution, it can often take a while, especially if a large user base will be impacted. For that reason, we believe that learning the history of a technology and what it looked like in previous iterations is time well spent.
Designing for the tension between simplicity and accuracy
When developing educational material, especially for bitcoin, there is often an inherent tension between creating something easy to understand and something that is technically accurate. To tackle this challenge, we had to get creative and expand on the ways the game could communicate and interact with users. Design played a critical role in this, allowing us to unlock new ways of thinking so more learning material could be presented and absorbed in a way that was not overwhelming.
Some places where this can be seen are:
- Chapter 2: Real time hashing driven by user input to demonstrate proof-of-work
- Chapter 3: Simulations to show the dynamics of pooled mining and 51% attacks
- Chapter 5: Color coding a raw transaction hex dump to see all the different parts
- Chapter 8: Visuals to illustrate how a blockchain can be similar to a tree like data structure
- Chapter 9: A drag and drop coding interface for script building and evaluation
- Chapter 10: Gamifying the process of opening up a lightning channel with an untrusted counterparty
Chapter 5 covers transactions structure.
Despite all the benefits that design delivers to the user experience, it is still of the utmost importance that every lesson goes through an in-depth review process. Every exercise has been thoroughly tested countless times by a number of contributors, including Bitcoin Core and lightning protocol developers.
Thorough review
One could create the best, most thoughtful, well designed learning material that follows a story and the job still wouldn’t be over. It is of the utmost importance that every lesson goes through an in-depth review process. For Saving Satoshi, each exercise was thoroughly tested countless times by a number of contributors, including Bitcoin Core and lightning protocol developers. This kind of testing resulted in many changes at nearly every point in the process. From the initial sketches of what an exercise would look like, to designing the wireframes, to actual implementation, to QA, we were always iterating to make sure the learning content was accurate, helpful to the player, and an overall good experience.
Made with educators in mind
Saving Satoshi offers an exciting opportunity for educators that want to integrate bitcoin into their programs. While the game certainly has enough material on its own for a strong curriculum, each chapter is full of additional resources and links for those looking to dive deeper. One thing that has been saving a lot of time is instead of gathering individual resources, we often use ChatBTC to provide additional context on a particular topic and to guide users to where they can get more information. ChatBTC formulates its answers from vetted sources like Optech, Delving Bitcoin, and the mailing lists, making us confident in the quality of service it provides.
By what could be considered a happy accident, the game itself follows a difficulty arc where chapters 1-3 are relatively easy before things kick up a notch. At the time of writing, chapter six supports two difficulty modes, normal and hard. A long term goal is to extend this to the rest of the game so Saving Satoshi can serve a wider audience without compromising on the quality of learning.
The game is also great for learning with friends, whether that’s in person or remote. In October 2024 the first Saving Satoshi workshop (in Atlanta, GA at TABConf) had roughly fifty participants that joined to play and work through the challenges together. Saving Satoshi contributors were available to answer questions and prizes were given to all attendees. To our delight many continued with the game after leaving the workshop!
Scalar School has been an early educational partner and supporter of Saving Satoshi. They host nightly sessions where participants play the game together on Discord. When applicable, an instructor takes students on deep dives of related material outside of Saving Satoshi like walking through Mastering BItcoin’s chapter on elliptic curve cryptography or exploring adjacent code in the Bitcoin Core repo.
Chapter 10 culminates in learning about constructing channels and making payments on the lightning network.
2. Story
Building a story around the words “Saving Satoshi”
Most stories are born from an idea. Few begin with just a title, and that is for good reason. Any writer will tell you that crafting a game’s entire storyline around a cool sounding phrase isn’t the best idea. This is because it’s difficult to work backwards and create an engaging, cohesive tale that leads to a very specific ending. Fortunately for Jonas who came up with the phrase “Saving Satoshi”, and unfortunately for our lead storywriter, the name “Saving Satoshi” was quickly set in stone due to a lack of writers at the project’s early stages. Thanks to this unusual decision, the Saving Satoshi storyline experienced no shortage or hurdles.
From as far back as the first brainstorming sessions, it was established that the game was going to be set in the future against some kind of sci-fi epic. It only made sense then to incorporate a historic, but yet-to-happen bitcoin event, the mining of the last satoshi. Because bitcoin’s supply cap is so unique to its design, this event is a big deal. Making it the focal point of chapter one was straightforward and since, at the time, it was just for a hackathon, there wasn’t concern about how a story like this may end.
Things quickly ramped up as work on chapters two and three began. It’s hard to write a story one chapter at a time, especially when it’s unclear where it’s all going. That’s when the team was fortunate enough to get help from Spiral in the form of one very talented lead storywriter that is rumored to actually be four cats behind a keyboard. With their help, a sketch started to form of what the full story would look like beyond chapter three. It was known that the game needed to end on a high note, with a sense of accomplishment that the player really did “save Satoshi”—even if “Satoshi” was more about the spirit that bitcoin was created on, and not the literal creator. That was the only story requirement. Everything else was fair game.
The plot thickens
Before long, ideas started flowing. The Thomas Vanderpoole character, an antagonist previously named Dr. Greg B.S. Wrong, began to form. An initial version of the story can be found here in our submission video for the first Bolt.fun Legends of Lightning Hackathon in 2022. It’s a fascinating glimpse at how far the story and visuals have come. For the lead storywriter, it was important that Vanderpoole was not 100% evil villain and for him to have some humanizing qualities. Even better was if he could have a redemption arc. Players will see that as they learn more about Vanderpoole’s background and personal connection to bitcoin, they are better able to understand his actions, regardless of how disruptive they are to the bitcoin network.
Another gem that came out of this phase is Holocat, a holographic cat that delivers clues and messages to the player. It took no time for her to earn the title of fan favorite, both internally with the team and with players. However all these new characters and ideas brought a big challenge. How can they all fit together and form a story that makes sense? If that isn’t difficult enough, the next question is how can the story be shaped around lesson content? Both tasks proved to be quite difficult but thankfully the lesson content was only scoped for a few chapters. For later material, the process was updated so the story and the lesson content were developed in partnership with each other.
The final review
The story was able to move at a considerably faster pace than development and after many months, it was done in spring 2023. However, the story doesn’t end there. Fast forward a year and a half later to late summer 2024 when the final chapters of Saving Satoshi were under development. That’s when the story underwent a final review. This review took several months to complete as it contained a countless amount of edits and updates.
While there weren’t any major changes to the plot, this final revision resulted in many smaller updates and one complete character redesign. User testing revealed that players wanted a more interesting character so after many rejected name proposals like Jessica Soup, Mike Ramen was replaced with the confident and adventurous Mika 3000.
A number of plot holes were also addressed at this time, some that had been there since the very beginning. These were cans that could no longer be kicked down the road, calling for deep collaboration between writers and bitcoin tech experts. Care had to be put into making sure the scenarios we were creating were not only technically sound, but that they still meaningfully drove the story forward. Many things were hashed out over phone calls and long comment threads.
World building
An especially fun part of story writing is creating a universe unique to the game. The team had fun reciting Holocat’s sassy one liners, imagining what sitting at a ButtLift Hover Desk would be like, and agreeing that no one would ever think to look for Satoshi’s keys on a CD-ROM labeled Creed – My Own Prison.
The universe really came to life at the first Saving Satoshi workshop where swag was created to represent different elements of the game like logos for the mining groups featured in chapter 3 and holographic Holocat stickers.
Swag created for the TABConf 2024 workshop.
While there were a number of things that didn’t make it into the final cut of the story these ideas have been saved for later releases. Look forward to a future update with a list of bitcoin themed cocktail drinks and much more!
Incorporating bitcoin culture and history
The story provides a unique opportunity to incorporate bits of bitcoin culture and history that not only enriches the overall game, but also balances out some of the more heavy technical material. Normally one would have to go to Twitter or Reddit to learn more about these topics, so it was great to be able to transmit this kind of information in a different way. Saving Satoshi is built by a team passionate about bitcoin. Bringing some bitcoin culture and history into the game yet another way to express that love.
Mentions of bitcoin culture and history can be found all over the game. The very first exercise in the game is to find the secret message in the genesis block (“The Times 03/Jan/2009 Chancellor on brink of second bailout for banks”). At several points in the game “don’t trust, verify” is taken quite literally like chapter 8 when users compute block subsidies and check that the longest chain adheres to the rules. When bitcoin Script is introduced in chapter nine, Holocat delivers a message about the OP_CHECKMULTISIG bug in Satoshi’s code that pops an extra item off the stack. In chapter ten players meet a character named Laszlo, a nod to the famous Laszlo Hanyecz who bought two pizzas for 10,000 bitcoin in 2020. Even the spirit of the game, one where the protagonist can be anybody but still save bitcoin, echoes the popular saying, “We are all Satoshi”.
3. Design
Powered by an immersive game UX, Saving Satoshi uses rich visuals and seamless interactions to journey players through time and space to learn about bitcoin coding. However, that is much easier said than done and the blending of story and education resulted in some unique design challenges.
An early ambition proposed by Christoph was to illustrate the story using generative AI. Compared to what is available today, the AI image generation tools of late 2022 were rudimentary. There was no shortage of issues including things like six fingered hands, inconsistent characters, limited resolutions, and little to no control over an image’s composition. Despite these inconveniences we stayed committed to this direction. There was just an expectation that we would have to iterate as the technology progressed. Fast forward to the end of chapter ten and that’s exactly what happened. While you may still see an extra finger or two, it’s clear that the quality of the art has made leaps and bounds. Christoph’s foresight in choosing this direction and betting on the future cannot be understated. The strategy worked out well and allowed the game’s visual storytelling to make huge strides.
An early and a recent rendering of Thomas Vanderpoole, showing how generative art has improved.
Consistent rendering of characters and environments allowed for more precise storytelling.
With all the progress being made, the technology keeps improving, and the team is planning to keep iterating the visuals over time to take advantage of the new capabilities and tell a more immersive story.
A second challenge was to create a learning experience that started gentle, and could slowly guide users towards more complex material and tasks. Each chapter was designed separately, carefully considering the lesson content, while also keeping in mind the other chapters for consistency and continuity. While whole team helped shape the user experience it was often the developers that gave especially important direction, since they are close to the target audience and understand the subject matter best.
Some of the unique interface components built for the learning experiences.
Third, it was important for the team to support smartphones. Many people around the world have one computer - their phone. A separate navigation and layout logic was designed to accommodate both mobile users and give them full access to the whole experience.
To peek into the design process, you can find the main design file here. The process for image generation is documented here. Plus, Christoph created various recordings of the design process.
4. Development
A big challenge in development has been thinking about incrementing difficulty and faithfulness to the realistic logic of bitcoin code.
We found that experimenting with new and unique components was key to finding the best ways to teach content and let users interact with the material. One thing to keep in mind was balancing this with the desire to keep development time as low as possible.
Supporting new contributors
Lastly is in creating an educational platform we have been trying to reduce the friction as much as possible for new contributors. While we are not directly a bitcoin app or program, we are a touch point for a lot of new bitcoin developers. It’s important to us that we do what we can to set new folks up for success, especially if one of our project goals is to create long term participants in the ₿OSS ecosystem. What some of this looks like in practice is having detailed templates for bug reports and feature requests, maintaining good documentation in the project’s README for things like how to run the code locally, and quickly responding to users as well as potential contributors over Discord and social media. It’s been a pleasure to see players do things like file GitHub issues and open PRs for translations for a number of different languages like Brazilian Portuguese and French. We look forward to continuing to welcome more contributors!
The script editor from chapter 9 is also available at script.savingsatoshi.com.
5. User testing
We collected feedback from users using several methods throughout the project.
Feedback Form
First, we established a feedback form that is linked from the “Help” section in the game. This leads to a Google Forms questionnaire that asks the player how familiar they are with coding and with bitcoin, as well as their thoughts on the overall experience.
Early Feedback
Second, we have been offering open invitations to bitcoin devs to try the game out and share their reflections. After giving Saving Satoshi a go, we chat with them on our weekly product team call where they can share out loud the things that stood out to them, what they liked, and what they’d want to see done differently.
Moderated User Tests
Third, we carried out more formal moderated user tests, especially early in the project when we were still working on the vision. This takes the form of a structured interview led by a product researcher like Art or Andrew. In the beginning, we defined broad personas for the game and invited people that fit those personas to recorded virtual interviews:
- Beginner developer with 1 year of experience with little to no experience working on bitcoin
- Senior developer with little to no experience working on bitcoin
- Experienced bitcoin developer
The scope was to test only one chapter per interview. To avoid influencing them, we asked open-ended questions and quietly observed how they completed the challenges.
We also tested a variety of hypotheses across the verticals of demographics, UI, UX, and lesson content such as:
- Demographics: This game is engaging enough for Senior Developers to continue playing.
- UI: Tooltip pop-ups triggered by a hovering mouse are intuitive.
- UX: This clue that appears after three failed challenge attempts will help the user move on to the next step.
- Lesson content: This topic and challenge won’t be too difficult for a beginner developers.
These interviews were then summarized and shared with the team.
In-Person Feedback
Fourth, we obtain mass feedback from events such as TABConf. During that event we led a workshop where roughly 50 people played the game at the same time. All the while, the product team was there to answer questions, address concerns, and gather feedback. This event also helped stress test the system and it was revealed that our infrastructure at the time was not able to handle a certain amount of load.
Dog-fooding
Lastly, the product team that built this game also happens to be the kind of user that we’re building it for. By replaying the game on our own, we provided ongoing, iterative feedback to each other about what delighted and what frustrated us.
All in all, the product team had several different sources of data and feedback about Saving Satoshi. This was used ongoing to inform features and ideas.
What’s next
Chapter 10 may be a major milestone for Saving Satoshi, but the project is far from over! At the time of writing, December 2024, there are still many things the team has planned for future releases. From design, to learning content, to community, these ideas are not confined to just one aspect of the project and instead span across many facets of the game.
Difficulty levels
One of the larger items on the to-do list is support for difficulty levels. In an ideal world, Saving Satoshi would be able to accommodate a variety of learners but currently, a solid understanding of how to code is a major requirement. It would be nice to one day support people that are just getting started and are new to coding. Conversely, it would also be great to make advanced exercises for those looking for more of a challenge. This has been implemented to some degree by sometimes moving hints to a separate help page, but there is so much more that can be done. At the moment, chapter six supports two difficulty modes (normal and hard). This was initially implemented as a proof-of-concept and the team looks forward to extending this functionality to other chapters.
Movie trailer
On the design and marketing front, a big dream is to do a movie trailer (here’s an early exploration from 2023) and poster. When the project first began, the AI image and video generation tools were nowhere near where they had to be to support something like this. A lot has changed in the last two years! Even just over the last few months, the design team has made some very impressive short clips to demonstrate what the technology today is capable of. It’s only going to get better and as it does, the possibility of a movie trailer becomes more likely.
Community involvement
In terms of community, the team would like to put more effort towards tapping into the larger bitcoin and software engineering ecosystems to share the game and partner with neighboring groups. If this sounds like you, hop into our Discord channel and get in touch with us! More educator tools like a guide for individuals that want to run Saving Satoshi workshops or a comprehensive list of topics that the game covers would help with this initiative.
Puzzles and interactive content
The team would like to continue exploring ways to make learning bitcoin tech fun, specifically through more interactive, puzzle-like exercises. This has been one of the project’s goals from the start and it’s one where there is always room for more ideas. The hope is now that version 1 of the game is out, there is bandwidth to iterate on some chapters and find additional ways to creatively engage with the player.
Conclusion
By design, Saving Satoshi is reflective of the best parts of bitcoin. It has endless rabbit holes. While a cultural transmission in itself, it also brings forth a rich and vibrant world of its own. It’s permissionless and makes players think in ways that they may not be used to. Like bitcoin, it’s 100% open source and built by a passionate group of contributors under the highest standards. It’s by the people, for the people.
It’s a labor of love.
We encourage anyone interested in learning more to play the game and join the community building Saving Satoshi. To get in touch, follow Saving Satoshi on GitHub and join the #saving-satoshi channel on the Bitcoin Design Discord.
Now be quick! Satoshi needs you.
Acknowledgements
Saving Satoshi would not be possible without the many people that have come together over the last few years to build it. The core team is made up of Adam Jonas, Christoph Ono (design lead), Satsie, BenAllenG (engineering lead), Matthew Zipkin (lesson content lead), Tuedon Tuoyo, Art Assoiants (product manager), and 4 mysterious cats that Spiral let us borrow to write the story.
Throughout the journey we have also had a number of contributors play key roles at various points in the game. This includes, but is not limited to, ecurrencyhodler, JT Woodhouse, JSMS, Kevin Karsopawiro, daviroo, nully0x, Vinayak Sharma, Shashwat Vangani, Aurèle Oulès, and sabakhilji.
A full list of code contributors can be found on GitHub.
Next, view the resources that can help you build better bitcoin products.