https://blog.frickjack.com/noreply@blogger.com (Anonymous)Sun, 26 Apr 2026 05:17:13 -0500Blogger http://www.blogger.com147125http://blog.frickjack.com/en-usnoReuben won't shutup!noreply@blogger.comhttp://blog.frickjack.com/2025/07/succeeding-at-failure.htmlnoreply@blogger.com (Reuben)Sun, 20 Jul 2025 15:27:00 -0500tag:blogger.com,1999:blog-34125606.post-6283836131707813895 A common interview question is, "tell me about a time you failed, and what did you learn from it". I was asked that question several years ago, and I replied with some examples of projects that failed, but I did not have a good answer for what I learned - another failure! I have several ideas about failure. First, if you never fail, then you're not trying hard enough; or you're not 0http://blog.frickjack.com/2021/07/tips-for-ardour-on-linux.htmlardourDAWlinuxnoreply@blogger.com (Reuben)Sun, 4 Jul 2021 14:54:00 -0500tag:blogger.com,1999:blog-34125606.post-1189798846565027596Problem and Audience Your browser does not support the audio element. A broad selection of digital audio workstation (DAW) software are available for Mac and Windows computers including logic pro, abelton live, and garage band. These popular DAWs are not available on Linux (which I run on my laptop), but several good DAWs do run on Linux - including ardour. Ardour has a rich set of features,0http://blog.frickjack.com/2021/07/gradle-to-sbt-for-scala3.htmlgradlesbtscalanoreply@blogger.com (Reuben)Sun, 4 Jul 2021 14:41:00 -0500tag:blogger.com,1999:blog-34125606.post-3318344237587526840Problem and Audience Your browser does not support the audio element. Scala 3 is an overhaul of the guts of the scala language type system and compiler that was recently released (in mid 2021) for general use. Unfortunately, the scala plugin for gradle does not yet support the new scala-3 build chain, so we ported littleware to scala's sbt build tool. Porting a gradle build to an sbt 1http://blog.frickjack.com/2021/06/little-ux-guidelines.htmlCSSdesignUXnoreply@blogger.com (Reuben)Wed, 23 Jun 2021 06:26:00 -0500tag:blogger.com,1999:blog-34125606.post-349699179724699861Problem and Audience A good understanding of a system's UX design drives the architecture of the underlying software that implement that design. The CSS rules, the site map and navigation experience, and the javascript component hierarchy and state management all rely on the developer's mental model of the design she is implementing. Unfortunately, many software developers like myself 0http://blog.frickjack.com/2021/06/jamstack-clouformation.htmlcloudformationcloudfrontjamstacks3noreply@blogger.com (Reuben)Thu, 10 Jun 2021 13:28:00 -0500tag:blogger.com,1999:blog-34125606.post-7563216283549164384Problem and Audience A simple clouformation template makes it easy to stamp out AWS infrastructure for a jamstack web site. A jamstack is a web site composed of static presentation (non-API) resources (html, css, javascript) assembled at build time - as opposed to a site that requires some kind of dynamic server side rendering of resources at request time. A nice feature of this architecture is0http://blog.frickjack.com/2021/06/route53-and-cloudformation.htmlawscloudformationroute53noreply@blogger.com (Reuben)Mon, 7 Jun 2021 14:33:00 -0500tag:blogger.com,1999:blog-34125606.post-5955429096864701203Problem and Audience Managing route53 records with cloudformation is a good idea for the same reasons that tracking other resources with cloudformation (or terraform or whatever) is better than clicking around in the web console - namely: it is less work to manipulate route53 records by editing json files than clicking through the web console tracking the cloudformation template and parameters 0http://blog.frickjack.com/2021/06/porting-httpsappsfrickjackcom-to-hugo.htmlhugojavascriptnoreply@blogger.com (Reuben)Wed, 2 Jun 2021 17:22:00 -0500tag:blogger.com,1999:blog-34125606.post-7053939507305374975Problem and Audience A web site may be architected in various ways: from a simple collection of static html, javascript, and css files behind a web server; to a site administered by a content management system; to a web application built on custom server or client side software. The appropriate design for a particular site is the one that best balances the requirements of the site's 0http://blog.frickjack.com/2021/05/simple-javascala-configuration.htmlguicejavascalanoreply@blogger.com (Reuben)Mon, 17 May 2021 17:38:00 -0500tag:blogger.com,1999:blog-34125606.post-6952851043642043723Problem and Audience One of the things every microservice needs is a mechanism for injecting configuration, so we developed a little json configuration helper for our littleware scala code that overlays a hierarchy of json configuration objects, and integrates with our module runtime and dependency-injection framework. Configuration in Littleware Littleware has a simple ServiceLoader based module0http://blog.frickjack.com/2021/05/supporting-cloudformation-patterns-with.htmlawscloudformationnunjucksnoreply@blogger.com (Reuben)Mon, 17 May 2021 14:35:00 -0500tag:blogger.com,1999:blog-34125606.post-1167198015914577426Problem and Audience Since cloudformation templates do not natively support the dynamic resource provisioning patterns required for many cloud architectures, various extensions and template generators have emerged (like CDK and SAM). The little stack tools allow the use of the nunjucks template language in cloudformation templates to support various infrastructure patterns. Overview of little 1http://blog.frickjack.com/2021/04/aws-codebuild-for-scala-docker-ecr-ci.htmlawscicddockerecrgradlescalanoreply@blogger.com (Reuben)Tue, 13 Apr 2021 15:06:00 -0500tag:blogger.com,1999:blog-34125606.post-6272344690482913135Problem and Audience A continuous integration (CI) process that builds and tests our code, then publishes versioned deployable artifacts (docker images) is a prerequisite for deploying stable software services in the cloud. There are a wide variety of good, inexpensive CI services available, but we decided to build littleware's CI system on AWS codebuild, because it provides an easy to use 0Chicago, IL, USA41.8781136 -87.629798213.567879763821153 -122.7860482 70.188347436178844 -52.473548199999996http://blog.frickjack.com/2021/04/setup-ecr-on-aws.htmlawsdockerecrnoreply@blogger.com (Reuben)Fri, 9 Apr 2021 13:03:00 -0500tag:blogger.com,1999:blog-34125606.post-5049995332093476579Problem and Audience Setting up an ECR repository for publishing docker images is a good first step toward deploying a docker-packaged application on AWS (ECS, EKS, EC2, lambda, ...). Although we use ECR like any other docker registry, there are a few optimizations we can make when setting up a repository. Overview We should consider the workflow around the creation and use of our Docker images 0http://blog.frickjack.com/2021/04/sign-and-verify-jwt-with-es256.htmles256jwtscalanoreply@blogger.com (Reuben)Fri, 2 Apr 2021 14:58:00 -0500tag:blogger.com,1999:blog-34125606.post-2062477751871943059Problem and Audience A developer of a system that uses json web tokens (JWT) to authenticate HTTP API requests needs to generate asymmetric cryptographic keys, load the keys into code, then use the keys to sign and validate tokens. We are building a multi-tenant system that implements a hierarchy where each tenant (project) may enable one or more api's. An end user authenticates with the 0http://blog.frickjack.com/2021/03/a-little-framework-for-scala-builders.htmlscalanoreply@blogger.com (Reuben)Sat, 20 Mar 2021 11:43:00 -0500tag:blogger.com,1999:blog-34125606.post-2491238231831772696Many developers use immutable data structures in application code, and leverage the builder pattern to construct the application's initial state, and progress to new versions of the state in response to user inputs and other side effects. The scala programming language supports immutable data structures well, but does not provide a native implementation of the builder pattern. The following 0http://blog.frickjack.com/2021/01/asynchronous-toolbox-pattern.htmljavascriptnoreply@blogger.com (Reuben)Wed, 20 Jan 2021 06:31:00 -0600tag:blogger.com,1999:blog-34125606.post-6250410466502485475A javascript application designer must structure her app to asynchronously load configuration and bootstrap its modules at startup. The asynchronous toolbox pattern addresses this challenge with a simple dependency injection framework. The Asynchronous Bootstrap Problem Consider an application with three modules in addition to modMain: modA, modB, and modC that export classA, classB, and classC0http://blog.frickjack.com/2020/07/little-tools-for-api-gateway.htmlawsnoreply@blogger.com (Reuben)Fri, 10 Jul 2020 06:28:00 -0500tag:blogger.com,1999:blog-34125606.post-3808901871440164061Introduction An API gateway on AWS provides a scalable and serverless platform for deploying an HTTP API backed by a lambda function, served to clients via a cloudfront cdn, and metered per client request. This architecture trades the traditional costs and complexity of maintaining a cluster of servers to host an API for a new set of challenges. The people (developers, QA, operators, managers) 0http://blog.frickjack.com/2020/02/install-local-packages-with-npm-link.htmlnodejsnoreply@blogger.com (Reuben)Sat, 29 Feb 2020 15:15:00 -0600tag:blogger.com,1999:blog-34125606.post-4162531379826525923 pre.code { font-family: "monospace"; padding: 10px; } In nodejs if you have a Bin package that depends on a Lib package, and before publishing a new version of Lib you want to test that local changes to Lib do not break Bin, then you can do something like this to link your local copy of Bin to your local copy of Lib: cd Bin/ && npm link ../Lib/ A problem with this (at least on Ubuntu0http://blog.frickjack.com/2020/02/simple-expressjs-logging-middleware.htmlexpressjsloggingnoreply@blogger.com (Reuben)Thu, 6 Feb 2020 00:39:00 -0600tag:blogger.com,1999:blog-34125606.post-7924382602279371372 There is a small trick to configure an expressjs middleware function to capture a request's run time and status. Here it is: .code { font-family: "monospace"; } const serverLogger = (req, res, next) => { const startMs = Date.now(); res.on("finish", () => { log.info( { req: { path: req.path, }, 0http://blog.frickjack.com/2019/11/simple-cicd-with-codebuild.htmlcicdCodeBuildnoreply@blogger.com (Reuben)Thu, 21 Nov 2019 05:06:00 -0600tag:blogger.com,1999:blog-34125606.post-2556999731677621925 pre { background-color: #eeeeee; } CICD is awesome. It automates the tasks we want to perform whenever we push code to our repository: test linting audit third party dependencies for security compile the code run unit tests publish artifacts There are a lot of great options for implementing CICD too. On-prem systems like Jenkins and Team City, and SAAS systems like Travis, CircleCI, 0http://blog.frickjack.com/2019/11/publish-web-content-to-s3.htmlawss3noreply@blogger.com (Reuben)Sat, 16 Nov 2019 09:47:00 -0600tag:blogger.com,1999:blog-34125606.post-1485747655116382460I host a little website at https://apps.frickjack.com by publishing static web files to an S3 bucket behind a cloudfront CDN. One way to improve the performance of an S3 web site is to configure each file's (s3 object) content encoding (gzip'ing the file if required), content type, and cache control at upload time (S3 natively specifies an Etag). Here's a little script that makes 0http://blog.frickjack.com/2019/10/executable-test-plans-for-bdd.htmlBDDjasminejsTDDnoreply@blogger.com (Reuben)Fri, 11 Oct 2019 06:52:00 -0500tag:blogger.com,1999:blog-34125606.post-8491814027862141907There are many good libraries for developing automated software tests, but we also want to allow non developers to specify test plans and acceptance tests early in the development life cycle. we want test plans and acceptance tests to help guide feature development we want to track test plans as artifacts in git we want to use Gherkin or some similar "living documentation" technology 0http://blog.frickjack.com/2019/06/hydrate-aws-account.htmlaws iam security devopsnoreply@blogger.com (Reuben)Sun, 30 Jun 2019 17:35:00 -0500tag:blogger.com,1999:blog-34125606.post-4931590077824972655You just got your brand spankin' new AWS account, and your team is launching like a rocket into the cloud. How should you set this account thing up? Before playing with EC2 instances and S3 buckets and all the other toys at the application layer of the stack; you should figure out how you want to authenticate, authorize, and monitor users manipulating your base cloud infrastructure. The 0http://blog.frickjack.com/2018/12/eks-and-aws-cni-ip-space-management.htmlawsEKSkubernetesnoreply@blogger.com (Reuben)Mon, 24 Dec 2018 22:43:00 -0600tag:blogger.com,1999:blog-34125606.post-5594318420851306770 AWS recently introduced its EKS managed kubernetes service which manages the kubernetes control plane (API and Etcd services), while the cluster owner administers the cluster's worker nodes in a VPC. One of the features of EKS is the VPC CNI networking plugin that tightly integrates with AWS VPC networking, so that each kubernetes pod is assigned an IP address from the VPC CIDR range allocated0http://blog.frickjack.com/2018/12/jwt-parser.htmljwtnoreply@blogger.com (Reuben)Mon, 24 Dec 2018 21:49:00 -0600tag:blogger.com,1999:blog-34125606.post-7679465539657966421 I just published a new JSON web token (JWT) parser app under apps.frickjack.com. There's nothing special about this app - it's just another little vanilla-js plus custom-elements app that continues the evolution of the little-elements and little-apps code. 0http://blog.frickjack.com/2018/10/little-elements-webapp-shell.htmlnoreply@blogger.com (Reuben)Thu, 11 Oct 2018 23:43:00 -0500tag:blogger.com,1999:blog-34125606.post-5929888269532721334 I recently updated apps.frickjack.com to use unbundled javascript modules to load custom elements and style rules. It worked great, except I soon noticed that initial page load would present an un-styled, no-custom-element rendering of the page until the javascript modules finished loading asynchronously... ugh. I worked around the problem by implementing a simple application shell. The html0http://blog.frickjack.com/2018/08/jasminejs-tests-with-es2015-modules.htmljasminejavascriptkarmanoreply@blogger.com (Reuben)Fri, 3 Aug 2018 13:22:00 -0500tag:blogger.com,1999:blog-34125606.post-1199821194774274341 Running jasminejs tests of javascript modules in a browser is straight forward, but requires small adjustments, since a module loads asynchronously, while jasmine's default runtime assumes code loads synchronously. The approach I take is the same as the one used to test requirejs AMD modules: customize jasmine boot, so that it does not automatically launch test execution on page load write 0