Monday, July 17, 2023

Why I created Underscore Backup

I started running a server for storing all my projects as well as various multimedia artifacts in 1999 with a small desktop computer and a 20GB HDD. As the size and personal importance of this server grew within a few years I started running RAID5 and then RAID6 to make sure data was not lost from single drive failures. Despite this, in 2006 the current incarnation of this server encountered a catastrophic 3-drive failure which I only managed to recover from after a tremendous amount of work and a fair amount of luck which included among other things manually patching the Linux RAID kernel code to remove certain fail-safes as I pulled data off the partially assembled RAID.

"The Server" in its current iteration.

This episode led me to look for ways to safeguard against this ever happening again. Looking through what options were available to me I found Crashplan which did address all my needs at a reasonable price. My initial backup to Crashplan took several years to complete over my 20mbit/s broadband uplink as my server had at this point grown to several TB.

A few years after I started using Crashplan they stopped offering consumer backups and the only way to keep using them was to migrate to their business plan which I did. However, Crashplan only allowed you to migrate a few TB per computer at the time which meant that I had to re-upload most of my backup again. Fortunately, at this point, I had gotten a fiber internet connection with a reasonable uplink that allowed me to re-upload this data in less than a year. As my backup of this server grew Crashplan also started showing its flaws where it required several GB of memory to be able to back up my server, but it did work and allowed me a reasonable peace of mind for the contents of my server.

This went on for a few years after which I was contacted by Crashplan (Now called Code42) and told that unless I reduced the size of my backup to under 10 TB, they would terminate my account since they considered me violating their terms of service by keeping too large a backup.

From: Support Ops (Code42 Small Business Support) 
Date: Feb 6 2020, 10:38 AM CST 

Hello Administrator,

Thank you for being a CrashPlan® for Small Business subscriber. We appreciate the
trust that you have placed in CrashPlan - that relationship is important to us.
Unfortunately, we write to you today to notify you that your account has
accumulated excessive storage, which will result in degraded performance. You 
have one of the largest archives in the history of CrashPlan. It is so large, we
cannot guarantee the performance of our service. Due to the size of your
archive, full restores of your backup archive, and even selectively restoring 
specific files, may not be possible.

As a result, we are notifying you, per our Master Service Agreement and
Documentation, to re-duce your storage utilization for each device to less than
10TB by June 1, 2020. Note that we have extended your subscription to June 1, 
2020 to give you ample time to make changes. If you do not do so by June 1, 
2020, your subscription will not be renewed, and your account will be closed at
the end of your current subscription term.


Thank you, 
Eric Wansong, Chief Customer Officer, Code42

The server I was using was Linux based and as far as I could tell Crashplan was the only competitor on the market providing cloud-based backup solutions for that OS. This was when I decided to start working on Underscore Backup as a means for me to continue making backups of my server as I couldn’t find any existing alternatives that fulfilled my needs. The first version was command line only and very primitive even though it did support point-in-time recovery, backup sets as well as obviously efficiently handling my very large backup. Another feature that was built in from the beginning was a strong focus on encrypting everything as much as possible so that any medium could be used for backups even if it was not properly secured from prying eyes. Creating the initial backup of my server using Underscore Backup used a more or less sustained 600mbit/s (To be compared with the at the time impressive 60mbit/s that I experienced using Crashplan on the same connection).

At the same time, I also started using the iDrive service for backing up my laptops and various other smaller Windows and MacOS based machines. I did this because I didn’t think the CLI (Command Line Interface) only implementation of Underscore Backup was just not convenient enough to be used on these machines). This situation continued for a few years when the CLI-only version of Underscore Backup backed up my server data to cloud block storage and my other machines were backed up by the iDrive service. This all came crashing down when my main development laptop of several years had a catastrophic SSD failure and I had to restore my data from iDrive. I found out two things about how the iDrive service works.

The first is that even though iDrive keeps track of versions of your files they do not keep track of directory contents and deletions of files. This is critical to any developer, and I restored a large developer repository with files that I have been working on as I have been running iDrive in the background. For those of you who are not developers, we rename files a lot. And every one of the old names of all my renamed files was restored back when I did a full restore of the contents of my laptop’s hard drive. That meant, that any repository of code that I had basically worked on since I started using iDrive was no longer in a buildable state without a considerable amount of work.

The second surprise to me was that even though to me the iDrive backup of my laptop was relatively small, only around 50GB in size it took almost 2 weeks to restore. Granted it contained a large number of files (Around 3 million, mostly small, files) but I was shocked at the slowness of its performance. I also opened up several support cases with iDrive about this but it was nothing they could do to help me. For comparison, on the same network with roughly the same sized backup in both files and total storage Underscore Backup would complete a similar restore in about 5 minutes (And it would do it properly keeping track of deleted files).

At this point, I evaluated other solutions available but could not find any that would be suitable for my needs. Carbonite does not allow you to specify what files should be backed up but instead in the interest of simplicity tries to be smart about it, when I tried it on my development files it decided to back almost none of them even though I specifically said to include the directory. Backblaze is a very solid solution but also does not keep track of deleted files for a true point-in-time recovery same as iDrive. In the end, I decided that I would put in the effort needed to create an easy-to-use user interface for Underscore Backup so that it would be suitable for use on things other than servers. The end result of these efforts was the first stable release of Underscore Backup in the summer of 2022 and which at that point graduated to be the only backup solution I used on all my computers.

The problem at this point though was that even though I had a backup solution that fulfilled all my needs it was still very tricky to set up for most users since to use it you generally had to supply your own cloud storage such as Amazon S3. It was also quite tricky to access data from other sources you had backed up since every source had to be set up individually on each client you wanted to restore the source on. The sharing functionality, even though present was also so complicated that I am relatively certain nobody managed to set this up except for myself. To solve all of these problems I decided to leave the service-less nature of the software I had followed up until that point and create a service to both remove the need to provide separate cloud storage and also help manage multiple sources and set up shares. This was a relatively large undertaking, but it eventually led to the launch of Underscore Backup 2.0 in the first half of 2023.

This current release as of this writing is the upcoming 2.2 release which has made it very easy to set up backup of multiple computers of any size while staying true to the original guiding principles of security, durability, efficiency, and flexibility.

This post was cross posted from the Underscore Backup blog.

Wednesday, April 26, 2023

Announcing Underscore Backup 2.0 and service general availability

First stable version of Underscore Backup with support for the companion service is now available. The service itself is also generally available.

Even with the new service, the main focus of the application is privacy, resiliency, and efficiency. The new service does significantly simplify setting up cloud backups and sharing though compared to use

The main new feature in version 2.0 is the introduction of a companion service that will help with many aspects of running Underscore Backup such as.

  • Keep all your sources organized in one place to easily restore from any of your backups to any other backup.
  • Help facilitate sharing of backup data with other users.
  • Optionally allow private key password recovery.
  • Easily access application UI even if running in a context where a desktop is unavailable, such as root on Linux.
  • Use as a backup destination. Storing backup data is the only feature that requires a paying subscription, giving you 512GB of backup storage for $5 per month.
  • Support multiple regions of data storage supporting North America (Oregon), EU (Frankfurt), and Southeast Asia (Singapore) regions to satisfy latency and data governance requirements.

On top of the companion service changes, the following features and improvements have also been implemented.

  • Added support for continuous backups by monitoring the filesystem for changes.
  • Introduced a password strength meter which requires a score of at least “ok” when setting up.
  • Switched from pbkdf2 to Argon2 for private key hashing function.

On top of the companion service changes, the following features and improvements have also been implemented. Get started by downloading the client now.

Tuesday, March 7, 2023

Building an online service on a shoestring budget

Photo by Josh Appel on Unsplash
Although I have been working professionally as a software engineer since I was 18 years old I have always had hobby projects I have been working with on the side and I generally take a somewhat perverse pleasure in figuring out how to build and launch these things on as small of a budget as possible. This post is an attempt to go through some of the things I have found that have helped me be productive and successfully build and launch several hobby projects.

I am particularly going to assume that this is for hobby projects and that the skill and time of the participants are free. If you are paying any salary that will dwarf anything you might save by aggressively using free tiers of online services. I am also going to assume your team is small (Less than 5).

What not to skimp on

First, let us go over the things you should not skimp on. The most important thing here is to not use any equipment or software from your day job. The reason for this is that if you do then your employer can usually claim ownership of any IP produced with their equipment. Also check your employment contract to make sure your employer doesn't have a clause to claim ownership to anything you do. That said, if you live in California, even if your employment contract does claim this it is not enforceable as long as you don't use company equipment, time, IP and you are not directly competing with your employer (See labor code 2870 for details).

One more of the things I would advise you to do is to enroll in school if you are not already. Being enrolled in a Community College only costs a few hundred dollars a year and will provide you with free licenses to a huge amount of tools for software development. Telerik, IntelliJ, Autodesk, and many more give students a free non-commercial license to almost their entire catalog of tools and libraries. Granted, once you get to the launch stage you will need to buy real licenses for your tools, but it will still save you tons of money in the development phase. You might even learn something doing it.

Basic development tools

I believe that if code isn't checked into a source repository with change tracking it basically doesn't exist at all. So, the first thing to do when starting a project is to pick a source code repository. GitHub is the giant in the field and they are fantastic. Not only do they give you free private repositories they also give you 2000 minutes a month of build executions (GitHub Actions). If you are building open-source applications you even get unlimited build executions for free.

Next you probably want to choose a cloud provider. I would pick one of either AWS or Azure. If you can go Serverless then I would go with AWS since they have a perpetual free tier for everything you need to launch a Serverless service. If not, then Azure Bizspark is a great program if you qualify. AWS also has a program for $300 to spend getting your prototype ready. Another tip for getting started on AWS is to get a new account for any new project. This is because they have an additional massive free tier that only lasts for 1 year after opening the account. It is also generally best practice to only run 1 microservice per account. Once the freebies are over you can tie your accounts together using AWS Organizations and SSO to help you keep track of them all (Doing this will usually invalidate the free tiers so wait a year after account creation to do this).

You also likely need a web UI testing tool. I use Cypress which has a free tier and is overall very good. They only allow 500 test suites per month so you can't run canaries in the free tier, but it should be sufficient for any deployment-based testing. They also provide a dashboard where you can see which tests have succeeded and failed with videos of the test execution so you can easily troubleshoot failures, something that is very useful when you integrate it into your CI/CD pipeline.

How to build your software

The key thing you want to avoid if you are launching something on the cheap is fixed infrastructure. If possible, use serverless functions instead of hosts or containers to host run your code. With some thought, almost everything you build can be run in a true pay-per-use manner. For instance, with AWS you should aim to use API Gateway, Lambda, SQS, and DynamoDB. As your service scales, you might consider moving off some of these for cost reasons but these primitives are also able to scale to thousands of transactions per second without any change to infrastructure if done right and none of them have a fixed cost. You generally don't want to use services such as Kinesis, Elasticache, Opensearch, relational databases, hosts, or containers since these all come with minimum fixed costs even if your service has no usage.

Useful services with good free tier

Here are a couple of other services worth noting with useful features and good free tiers.

  • Google Analytics is ubiquitous for site analytics. It is having privacy issues in the EU though with several countries declaring it illegal recently. Another option that I use that with more of a privacy focus is Clicky.
  • Also useful from Google is Firebase which provides a lot of features such as a basic user database, usage analytics, and monitoring among others. It is a great choice if your primary use case is a mobile app. It is pretty inflexible for building complex applications or services though and you probably want to go with a normal cloud provider for that.
  • Cloudflare is Web Application Firewall and has a very useful free tier. They also provide a privacy-focused and less annoying CAPTCHA service called Turnstile.
  • Blogger is a free blogging platform. It will generally not let you build your entire website like Wordpress will, but if all you need is blogging it does that well and allows you to use custom domains for free. 
  • Crisp is a great platform for providing support for your site and they have a nice free tier for getting started.
  • Auth0 provides a platform for helping you do auth of your users and has a decent free tier to get you started.
  • Most of the payment processors such as Square, Stripe, and Braintree only charge a percentage with no setup costs. Their fees are very similar, I prefer Stripe myself only because they have fantastic developer documentation.

Launching and running a service

As you first start out I tend to not think too much about schedules and deliverables. The reason for this is that I do this for fun and the best way to kill the fun is to start making yourself a slave to delivery commitments and launch dates. That said as you get closer to launch I really do think you need a way to keep track of remaining tasks and open bugs etc. In my opinion, Jira from Atlassian is by far the best and most comprehensive tool for this and as long as you have a small team everything you need is available for free.

You will need monitoring of your service before you go live. Both AWS and Azure have built-in monitoring tools and they work well. Also worth mentioning again in this space particularly is Firebase which does have some monitoring and analytics capabilities. Another service in this area that has a good free tier is New Relic. One thing that neither AWS nor Azure has is paging for when things actually go wrong. The tool that I found here that has a very functional free tier is Pager Duty, that said you are likely to want to upgrade from the free tier pretty soon as your service takes off to be able to have more control over your escalations.

Your service will likely need a single place to aggregate everything that is going on in one place such as task completions deployments and any issues and here Slack is hard to beat and have a great free tier.

Be frugal, not cheap

As a parting word, I would like to point out that although figuring out how to build and launch your service cheaply don't let that stand in the way of building your service right. Never pick the cheap option over the correct option, you will always regret it in the end.

For me, one of the main reasons why building things in a frugal way when I am working on hobby projects is that it allows me to have fun doing them longer because I don't have the pressure of needing to be done and launched fast because I am bleeding money during the development phase.

Being frugal during the development phase might also allow you to retain a larger portion of your equity if you actually launch your service because it will reduce the amount of help you will need to get started before you get a customer base. As an example, one of my previous projects Your Shared Secret literally has $0 per month of fixed cost. My more recent project Underscore Backup is not quite that cheap but has a fixed cost of less than $50 per month. Most of that cost is for CloudWatch alarms, KMS keys, and Dashboards.

Friday, February 24, 2023

Started another blog

Created another blog at for more shorter snippets of what I am working on right now. Really its just something to put on this domain that I've had for a while now without doing anything with it.

Thursday, February 16, 2023

Launching Underscore Backup service and first beta of the version 2.0 of Underscore Backup application to use it

Finally launched the first public release of the Underscore Backup service. A backup service that is a companion to the Underscore Backup application I have now been working on for a few years. I am really excited about this since adding a service component to the application solves a couple of user pain points with my previous releases, such as.

  • Its now easy to coordinate and keep track of multiple sources so you can easily restore data from another computer you are backing up.
  • It comes with the ability to use the service for storage so that you don't have to deal with configuring S3 or something similar. The storage also supports 3 regions in the US, EU and the Asia Pacific region and is priced lower than S3.
  • It makes it easy to set up sharing between users.
  • The service can provide optional secret key recovery.
  • You can easily keep track of where the administration interface of the application is available even if the application is running in a context that does not have access to your desktop.

There is also a ton of other additional features included such as improve password hashing algorithms, log rotation, integrated password strength meter and built in new version notification.

You can head to the site to download the latest version and sign up for the service. The service is entirely free, however you do need a subscription for using storage as detailed on the pricing page.