Tech Stack

Our goal is to find out how to employ and scale digital credentials to create recognition for skills, competencies and learning achievements for vulnerable groups. Those groups (e.g. migrants, unemployed, school drop-outs, single-parents) may have competencies acquired outside of formal education, but no feasible representation or recognition for them. Or they may want to acquire new competencies and skills, but may not afford to benefit from formal education, and thus not be able to demonstrate it. Digital credentials, especially OpenBadges have the potential to solve this, if they meet the requirements of these groups.

Can Open Badges solve this on a technical level?

As part of our first research output, we set to understand how the technical solutions, implementations, ecosystems and services support this potential, with the strong focus on vulnerable groups. This turned out to be more challenging than expected. Many projects and services started several years ago, are still “visible”, but often defunct, taken over, or remained at a proof-of-concept stage. You need to knock on every door to see if there is life inside. In many cases, you need to register to get inside, to be allowed to look around, and in some cases not everything can be shown. Therefore this overview is likely not complete, and we would be grateful to any additions, corrections, notes that you think might improve it – please comment below.

Overview of Digital Credentials

At the very core, Digital Credentials and OpenBadges are in a triangle of interactions:

This triangle represents the interactions between the three players: The learner (or earner, or holder), the issuer (or educator) and the consumer (e.g. employer, job agency). This triangle applies for analog (paper), digitalized (pdf) and digital credentials, but a digital credential can in theory be issued and shared much more easily –  as a link or a file. Furthermore, a digital credential can contain more information, or links to those, in a structured way, which enables new uses for it. The type and structure of information a a digital credential can hold, is typically narrowly specified. There are “vast” specification for credentials, e.g. by the W3C as in the W3C-VC-EDU for verifiable credentials, with many technical requirements for implementation. And there are slimmer specifications, like the OpenBadges2.0 specification.

There are many types and implementations of digital credentials, often proprietary, or accessible only within a commercial context. We specifically looked into Open Digital Badges, as they cater to the requirements or our target groups, – with their characteristics of portability, small granularity, verifiability and general openness. To “locate” OpenBadges in the spectrum of credentials, the following visualization of Don Presant and Doug Belshaw can be helpful:

What is an OpenBadge?

All recent digital badge programs within the scope of our project were built on the OpenBadges 2.0 specification, which was developed by the IMS global consortium, based on prior specifications of other groups (Mozilla and MacArthur Foundation, Badge Alliance).

The key concept of OpenBadges is to use (“bake”) a PNG or SVG image file (the “badge”) with integrated structured information about the learner (“earner”, “holder”), the issuer, and further context information to document the assertion (skill, learning achievement), including URLs and signatures. The resulting PNG or SVG image file can be displayed in any browser.

Although the resulting image file is displayable on most current devices, the data within requires specific software, or a host or intermediary to access and display it. And this is where the tech or provider stack becomes important, because the potential of OpenBadges is dependent on the technical enablers.

The following chart gives an (incomplete) overview of those providers, which is then reviewed in the according chapters.

Issuing Open Badges

How can I issue an OpenBadge to an earner?

Starting with the issuer perspective, there are basically four options to create and submit an OpenBadge:

  • Manually creating a file and sending it to the learner / earner
  • Through an LMS (Learning Management System) plug-in
  • Through a hosted service without LMS
  • Through an LMS integration of a hosted service.

Manual issuing

While it is possible to design and create an OpenBadge manually, it is probably an edge case. It show cases the openness of the technology and specification, but maybe prone to erroneous implementation and thus limited value for the earner. Further, the receiver is dependent on additional technical infrastructure for actually seeing and managing the credentials (see below).

LMS -> Plug-In

A Learning Management System (LMS) is a feasible way of issuing OpenBadges, as they allow for seamless interaction flow between the educator / issuer and learner. However, they may not have the feature set and comfort that a hosted provider offers, e.g. designing a badge class. notes that using a plugin in a LMS may lead to “Badge rot”, among others.

LMS -> Host Provider

There are many providers that allow to create, issue, manage, track OpenBadges through an integration into the issuer’ LMS systems, through plug-ins or APIs. Those providers typically have different plans and service-level-agreements, depending e.g. on the amount of issued badges, and additional features. Examples are Badr, Credly, Acclaim, OpenBadgeFactory.

Issuer -> Host Provider

As another option, the OpenBadges are directly issued through the host, which provides an administration interface. All reviewed hosts provide this option, if only for demo reasons.

This short overview of the interactions between the involved parties indicates that issuing OpenBadges likely requires a hosting provider, to reduce risks and improve the reliability for the learner / receiver.

Receiving OpenBadges: Wallets / Backpack

Where can I store, collect, access and show my credentials?

Though an OpenBadge is a PNG (or SVG) image file that the learner can receive through email or download to and view on a local device (phone, computer), the deeper and digitally relevant information can not be easily accessed and displayed. This is where a wallet comes into play.

A “wallet” is a digital container for personally achieved and / or accepted digital credentials of a learner / earner. Mozilla, as the founder of OpenBadges, called its wallet initially “Backpack”, and the term is still used in publications and projects. A wallet or backpack is both a collection and a display container, and typically has further features. It can be a (mobile) app, or a service (host), provided through a website.

Mobile / local wallets

To our knowledge, there are only four mobile wallet apps implementing OpenBadges, where a learner can collect their OpenBadges (Android or iOS). Also, we could not find any desktop app.

  • BadgeWallet (Badgecraft)
  • Open Badge Passport (OpenBadgeFactory).
  • BlockCerts Wallet (Hyland)
  • (BadgeGram

All four seem to have limited functionality.

  • BadgeWallet allows to share a single badge through the phone’s app, and sends an image and the link to where the badge can be shown on a Badgecraft server.
  • OpenBadgePassport allows to share a single badge through the phone’s apps as a link to an OpenBadgePassport server, and requires the badge to be made “public” beforehand.
  • The BlockCerts app could not be further evaluated, as it seems to allow only badges issued through an issuer within BlockCerts.

We also found out that Credly has a “add to wallet” function, which saves the OpenBadge to a local wallet (as pkpass file), but without support for further features.

To our own surprise, we have not found any significant mobile wallet app that is independent of a host provider (with the exception of BadgeGram, which demands the login data for Badgr, but which seems to be without a significant user base). This is a particularly relevant finding when looking at vulnerable groups, who may not be able to be able to gain education through a program that has sufficient financial capacity to purchase hosted services.

Hosted wallets / hosts

There are several web based wallet providers enabling users / learners to manage OpenBadges:

Some of those wallet providers have limited or no import functionality for users, thus allowing only badges that were issued within their “walled gardens”, e.g. Credly, or

The three “big commercial” host providers Credly, Badr/ConcentricSky and Accredible allow the issuer to connect badges with skills, which are then displayed on a public badge page.

Worth mentioning is the Europass 1.0 as an initiative “to increase transparency of qualification and mobility of citizens in Europe”. in theory, it allows a badge holder, to upload OpenBadges to their account, but it does not display the included meta data, nor provide any features on top of that. Further, we rate this import process as less than usable. While we see the potential for it to work as a credential wallet for EU citizens, its current implementation is not beneficial to the promotion of OpenBadges, or micro-cretentials in general. We hope that the upcoming Europass 2.0 includes and implements support for OpenBadges in a usable way.

LMS Hosts

OpenBadges can be directly issued through an LMS (Learning Management System), and in most cases, they can also be accessed there by the learner / earner. At this point, we have no information how feasible it is to add / import externally acquired OpenBadges into LMS, e.g. Moodle. In any case, we see a strong “Lock-in”, similar to hosted wallets, with potentially no guaranteed lifetime access.

From our perspective, this constitutes an important topic, which is often ignored in digital credentials research: looking into OpenBadges over the past 10 years, we observe commercial hosts coming and going, companies fold or sell – and the credentials they have offered to learners are at times non-transferable – therefore, learners tied to a certain host may lose their credentials without being given a possibility (or the knowledge) to save / transfer it to a different provider.

Blockchain “Hosts”

If we think of a wallet as a location where the user can store, access and share awarded OpenBadges, the blockchain as a decentralized, robust “database” provides another constellation that potentially replaces a host or intermediary. The learner has access to awarded OpenBadges in form of tokens, which then can provide different options e.g. to share or give fine-grained access to third parties. This would require a local or hosted wallet on the learner’s side.

Looking at our target group, and following Alex Grech et. al., we see strong benefits in this approach, mostly because it has the potential to give self-sovereignty and ensure interoperability for a group, that otherwise may lack the resources to guarantee or access or complete their learning and achievement records and credentials. It is beyond the scope of our desk research to go deeper into the potential of the blockchain for lifelong education and recognition of learning achievements, but we see evidence of the strong potential to meeting the needs and requirements of our affected learner groups.

Grech et. al show the interactions within that setting with the following chart:


As of beginning of 2021, we found several projects and initiatives around blockchains in the educational area that typically use Etherium with its smart contract capability. This includes e.g. the service BCDiploma, which provides an issuing platform based on OpenBadges 2.0. Another platform is Blockcerts, which originated from a project of Learning Machine and the MIT Media Lab in 2016, to “release […] the first open-source codebase to issue, hold, and verify digital records using blockchain-based verification”. This project is now “actively stewarded” by Hyland Credentials, which provides a commercial solution for credentials. Other projects seem not to have left the “Proof-of-Concept” level, like BadgeChain or The Open University and KMI.

The Erasmus+ funded project Credentify aims at providing an “API service in the cloud that enables universities and students to issue and receive micro-credentials that can be stacked into ECTS”. It remains to be seen how it could also provide an infrastructure for non-HEC stakeholders.


How can I give access to my credentials?

Sharing is at the core of an Open Digital Badge. It can mean advertising skills, competencies or learning activities in social media or other public or semi-public contexts; it can mean sending the badge as an attachment or via direct message to a recipient (although that requires a way of accessing the embedded meta data); it can mean sending a URL of a public wallet that the recipient can than access and see.

All hosted wallets we listed previously allow sharing of a single badge via url, but show different implementations:

  • OpenBadgePassport requires a public status before allowing the sharing setting.
  • In Badgr, to our knowledge, all badges are public. Badgr further allows to create an iframe with configurable detail options.
  • BadgeCraft allows setting limitation of access (both for the badge and the “evidence” on five levels through the platform, e.g. to a project).
  • Sharing all or selected badges as a portfolio or collection is possible e.g. with Badgr (see example here).
  • OpenBadgePassport allows to create a “profile” with additional content, including goals.
  • OpenBadgeFactory provides statistics for a single badge, and integrates several features of a social network, like following a specific user, endorsements, “congratulations” or “spaces”.

From the perspective of our target group, and of self-sovereign sharing in general, all platforms bind the “earner” to their own platform.


How can I identify myself to get access to my badges, and show that they are accredited to me?

For an “earner” it is essential to be able to connect learning achievements to the own identity, in a trustable, verifiable and controllable way. Disruptions in access or resources may lead to the inability to provide evidence to learning achievements or skills, and thus reduce the chance of recognition.

Digital Badges are awarded to a single person, as reflected in the OpenBadges 2.0 specification (“identity”). However, the connection between the receiver and the identity is nearly always covered solely through email, and host providers, like Badgr, Credly or Accredible check that identity through email validation (confirmation email). In other words, the identity of an earner is reflected through an email address, existence of an easily accessible email address is crucial, which poses a certain dependency and risk towards the email providers. On the other side, it allows users to have several “identities”, which can have benefits in avoiding profiling or tracking.

In many cases, an issuer has a direct connection to an earner / learner, e.g. through an LMS with a required email and other registration data; or through direct physical contact and the ability to collect and validate identity information.

One European project that uses a stronger ID connection is, employing the eduID, which is specifically designed to create a unique and digitally verifiable ID for students of higher education. This eduID was used to issue EduBadges based on OpenBadges.

Europass currently has no identity validation, and registration is simply through email.

As of Spring 2021, also due to the Covid-19 pandemic, many countries and the European Union are speeding up their efforts to establish and provide a digital ID to their citizens, which may open up opportunities to connect and use that ID to (Open) Digital Badges. One such initiative is IDUnion. However, we cannot judge at this moment if vulnerable groups may be able to benefit from this progress.

Verification and validation Providers

How can I make sure / show that the Badge was not changed / manipulated?

All involved parties have an interest in trusting digital credentials. This need for “digital trust” opens the field for a variety of service providers on different levels. OpenBadges 2.0 does not have a built-in mechanism to validate the integrity of the information, but when a badge (file) is created it can be hashed, and this hash code can be verified through those who have issued the badge, or host it, or who have stored that hash code in other places (e.g. blockchain); or it can use JWS as a signing mechanism.

How can I show what I have done to achieve the badge?

OpenBadges 2.0 can contain information about the “evidence” of an assertion, and the criteria. This information can be contained within in the Badge, or through an URL pointing to that information, e.g. to an issuer’s website or LMS (Badge Class). Reading this information in the OpenBadge requires typically a host (“displayer”).

Skill and competency representation

How can I demonstrate a skill or competency through earned digital badges?

This question and pain point for learners opens a wide field of initiatives, discussions, laws, rulings, regulations and conditions, that can not be covered or even touched on more than a superficial level. At the same time, this is probably the core pain that needs to be addressed and solved for disadvantaged groups or those distant to the labour market, and for societies in general. And it is also the core lever that we see and envision to incentivize non-linear, non-formal, informal and lifelong learning, for any user group.

With the decreased representation of formal degrees towards skills and competencies (often referred to as the “skill gap”), qualifications represented through other types of (digital) credentials can potentially meet the demand of the employment sector for more fine-grained, current and non-academic skills. This is addressed e.g. through the Open Skills Network and its current pilots.

There are many policy-related initiatives on all national levels, such as CEDEFOP, the “new Europass“, “America Succeeds“. Often it is addressed in the context of up-skilling, re-skilling, 21st century skills, soft skills or transversal skills.

On a technical or solution level, this “mapping” between learning achievement, evidence and criteria, and skill / competency is on a preliminary level, at best.

Stackability, Recommendation and Analytics

What should I learn next? What can I do with my skills and learnings?

One of the potentials of digital credentials, including OpenBadges, lies in the ability of computers to analyze the relationship between the achievements, skills and competencies that they represent. This information can be used to create value in different directions.

Stackability can be defined (as by the U.S. Department of Labor) as “part of a sequence of credentials that can be accumulated over time to build up an individual’s qualifications and help them to move along a career pathway or up a career ladder to different and potentially higher-paying jobs.” In more general terms, stacking qualifies you for something else, potentially bigger. It can be differenciated into three types: 1. Vertical: Credit-bearing towards larger qualification; 2. Horizontal: Credit and non-credit bearing standalone; 3. Diagonal: Combinations or variations of vertical and horizontal stacking.

For learners distant to the labour market or lacking requirements for more formal education, stackability of credentials holds a very strong potential. However, stackability can only be built on a defined relationship between learning steps, skills and competencies, represented through digital badges.

Stackability is also often connected to the topic of “unbundling” in higher education, as summative degrees gives little access to the learned skills and competencies.


As Chakround and Keevy wrote in 2018, “to date there has not been an efficient national or global system to collect, connect, search and compare up-to-date information about learning outcomes and credentials in a common language or format that can be universally understood and easily accessed. This lack of information and systems contributes to confusion, lack of trust and uninformed decision-making regarding the recognition of skills and qualifications within and across borders. It also leads to talent loss for economies and employers.”

As of 2021, it seems little has changed. On the contrary: many projects, platforms and service providers with the potential ecosystem of (Open) Digital Badges ceased to exist or be maintained, while other beneficial or crucial components (like a feature rich, user-friendly, badge-agnostic (mobile) wallet) are missing. The fragmentation of the technical echosystems is likely a barrier for the acceptance of (Open) Digital Badges, especially for those groups lacking digital competencies or resources, for learners, issuers and consumers.

Futhermore, it increases the power of remaining commercial full-stack “one-stop” providers that by nature tend to optimize business value, benefit from closed systems and lock-ins, and focus on commercial needs more than societal goals or the promotion of the individual learners.

As to this date, there seems to be no simple answer to “where can I collect my badges”, “where can I issue badges to learners” and “where can I access the badges of a learner”.