Series · 15 parts
An Attendance Platform in ASP.NET Core
Badge gates, WFH timers and shift allowances - the shape of a seven-project intranet attendance platform, the onion it almost is, and the roadmap for fourteen more parts.
Topic
.NET
221 articles filed under this topic.
Series in .NET
Series · 4 parts
An Attendance Platform — The Frontend Chapters
A 6.23 MB JavaScript bundle loaded on every page, a manifest that minifies CSS but concatenates JS, and two copies of jQuery - the first of four frontend chapters the attendance series skipped.
Series · 9 parts
Archive-on-Delete with ArchiveKit
Hard deletes destroy the audit trail; soft deletes clutter live tables forever. Introducing ArchiveKit, a .NET library that intercepts deletions and stores immutable archive snapshots with TTL policies and cascade archiving.
Series · 8 parts
Contract Testing with Pactify
Unit tests mock what you assume, end-to-end tests tell you too late - consumer-driven contract testing closes the gap, and a small open-source .NET library called Pactify is the clearest way I know to learn how it works. Part 1 of a series.
Series · 8 parts
Convey — The Missing Chapters
The 22-part Convey series read the packages; it never once walked the sample system that ships with them. Opening the missing chapters with the trip an order takes through Orders, Pricing and Deliveries — and what the samples quietly teach that no package README does.
Series · 10 parts
Entity Versioning with VersionKit
Rename a property, change a type, ship the release - and every payload you stored last year stops deserialising. Introducing VersionKit, a .NET library that declares schema history as attributes and migrates old data on read.
Series · 17 parts
FastEndpoints in Depth
Controllers grow sideways and Minimal APIs grow into soup. FastEndpoints bets on a third shape - one class per endpoint - and this series reads its source to see how the bet is implemented. Part 1 of FastEndpoints in Depth.
Series · 12 parts
FastEndpoints — The Missing Chapters
Seventeen parts of reading FastEndpoints and the series never once mentioned mappers - the entity-translation layer half the endpoint base classes exist to serve. The Missing Chapters opens with the biggest gap: where mappers live, how they are found, and why they are secretly singletons. Part 1 of FastEndpoints — The Missing Chapters.
Series · 22 parts
Microservices with Convey
Every team's fifth microservice ships with the same four hundred lines of bootstrap code as the first four. Opening a deep-dive series on Convey, the open-source .NET toolkit that turned that boilerplate into thirty composable packages.
Series · 10 parts
Multi-Tenancy in .NET with EF Core
Database-per-tenant, schema-per-tenant, or packed into a shared database? Kicking off a series on building a multi-tenant platform where one EF Core codebase supports all three isolation strategies behind a single control plane.
Series · 15 parts
Nine Services and a Message Bus
DShop is one e-commerce shop stamped out as nine microservices over RabbitMQ - this series reads the real source to see how the topology holds together and where it drifts. Part 1 of Nine Services and a Message Bus.
Series · 11 parts
Real-Time Feeds with FeedR
A guided tour of FeedR, DevMentors' open-source .NET microservices sample for real-time data feeds - six services, Redis pub/sub, Apache Pulsar and a gRPC stream, and the two-tier eventing model that makes it worth reading. Part 1 of a source-level deep dive.
Series · 9 parts
Sagas with Chronicle
Split one database into five services and the transaction you deleted does not disappear - it goes feral. On sagas, compensation, process managers, and Chronicle, the small open-source .NET library this series reads line by line.
Series · 8 parts
Service Discovery Without a Service Mesh
Dozens of Azure Functions and Logic Apps need each other's URLs and keys, and there is no Kubernetes, no sidecar, no mesh to hand them out. How a small .NET library turned one Key Vault and a naming convention into a working discovery layer - the consumer side of a registry made of secrets. Part 1 of a new series.
Series · 13 parts
The Convey Consumer Tax
Convey sells a microservice in thirty lines, and Pacco builds ten of them - this series reads the whole estate to price what the framework compresses and what every consumer pays for by hand. Part 1 of The Convey Consumer Tax.
Series · 18 parts
The Database Is the Message Bus
Five executables, zero queues - how an attendance platform coordinated a web app, three Azure Functions and a console job through one SQL database, and what that choice bought and cost. Part 1 of the series.
Series · 16 parts
The Framework Before the Framework
DShop.Common is the shared library nine microservices were built on - and the rough draft of a framework its authors later shipped as Convey.
Series · 15 parts
The Order That Choreographs Itself
Nobody in Pacco approves an order - a vehicle reservation does. A tour of DevMentors' parcel-delivery estate, the domain it models, and the fifteen-part series it earns.
Coming soon in .NET
The Dashboard You Get for Free
Wire four services into a .NET Aspire AppHost and run it once - traces, logs, health and environment variables for the whole system, before you have written a single line of observability code. Part 1 of a series on Aspire in production.
Standalone articles
Getting Transactions Right with EF Core
SaveChanges is already a transaction, until it isn't enough. A tour of explicit transactions, TransactionScope, execution strategies and the failure modes that only show up in production.
Three Ways to Borrow Another Service's Data
Four Pacco services need customer data and no two agree on how to get it - Orders and Parcels keep id-only replicas fed by events, Availability phones home mid-command, and Pricing pulls the full details document to count one number. One upstream, three consistency stances, five representations of the same entity.
Same Fact, Two Names
Inside the Customers service a registration completes - and the rest of the estate hears that a customer was created. Three lines of EventMapper perform the best ubiquitous-language translation in Pacco, sitting on top of a lifecycle state machine with one guarded transition and four administrative jumps.
The Parcel That Wouldn't Leave
Order.DeleteParcel raises a ParcelDeleted event and never removes the parcel from the set, while Parcels' cancel and delete handlers detach exactly one parcel of many. Two bounded contexts maintain the same association independently, both with bugs, and end up permanently disagreeing about a fact.
Publishing Pacts: From Shared Folder to Broker
How a pact travels from the consumer's pipeline to the provider's - Pactify's file and HTTP publishers, Pact Broker URL anatomy, and the unchecked response status that makes a failed publish silently pass your build.
Rejected Events and How They Rot
Convey's IRejectedEvent gives Pacco an application-level negative acknowledgement - a rejected twin for every command. Reading the four exception-to-message mappers shows the pattern decaying in four different ways, from a failed reserve announced as a failed release to rejection classes nothing ever constructs.
Correlation by Natural Key
Availability's ResourceReserved event carries no order id, no correlation id, no saga id - just a resource and a date. Orders finds the right order anyway, by treating (vehicleId, deliveryDate) as the correlation key, and the expropriation flow shows exactly when that key stops being unique.
How to Delete a Family Together
Correlation ids and cascade archiving in ArchiveKit - how one Guid per save turns scattered archive rows into a reconstructable object graph, why cascade happens through the EF change tracker rather than the database, and two honest limits: a naive root heuristic and a CascadeArchive flag the interceptor doesn't read yet. Part 6 of the Archive-on-Delete with ArchiveKit series.
The Streaming Seam: Redis Pub/Sub Behind an Interface
FeedR moves every tick between services through a two-method streaming abstraction with a no-op default and a Redis implementation - which, despite the namespace, is pub/sub rather than streams. What that seam buys, how DI last-wins overrides it, and what you lose when nobody is listening. Part 4 of the FeedR deep dive.
A Checkout With No Conductor
Pacco's flagship flow reconstructed from source - a vehicle is assigned, a reservation lands, an order approves itself, and when a VIP bumps the booking the cancellation ripples through three services with no process manager in sight.
One Event, Five Contracts
Every transition of Pacco's Order raises the same domain event - OrderStateChanged - and a mapper switches on aggregate status to mint five distinct integration events. A content-based router keyed on state, weighed honestly.
The Decorator Seam: Logging Handlers You Didn't Write
How Convey wraps every command and event handler with template-driven logging using one attribute, a Scrutor decoration — and a reflection trick against Scrutor itself that I admire and would never ship.
The Reservation That Bumps You
Availability's Resource aggregate enforces one real business rule - a higher-priority reservation evicts yours and announces it. The invariant, the struct value object behind it, and the day-integer it becomes on disk.
Paying Down the Migration Debt
Lazy migration makes deploys instant but taxes every read of old data. VersionKit's backfill service rewrites stale payloads in scheduled batches until the store converges on the current version - in a host, or from a serverless function. Part 6 of the Entity Versioning with VersionKit series.
One Message, Many Sagas
services.AddChronicle() registers sagas you never mentioned, and one ProcessAsync call can run five of them in parallel. Inside Chronicle's Scrutor scan, the seeker's dedupe trick, and the ref-counted lock that serializes each saga id.
Three Ages of a Domain Model
Same framework, same four-project layout, three maturities - Parcels publishes from handlers, Orders raises events and maps them inline, Availability runs a full pipeline. The lineage made diffable.
The Order That Choreographs Itself
Nobody in Pacco approves an order - a vehicle reservation does. A tour of DevMentors' parcel-delivery estate, the domain it models, and the fifteen-part series it earns.
Eight Sources, One DTO: Model Binding Under the Hood
FastEndpoints binds a single request DTO from JSON, form, route, query, claims, headers, cookies and permissions - in that order, with compiled setters cached per DTO type. Reading the binder explains every binding surprise I have ever hit. Part 4 of FastEndpoints in Depth.
The Rough Draft of Convey
A retrospective on DShop.Common - the frozen shared-contracts tombstone, a release candidate pinned forever, and a concordance of what Convey kept, renamed, and fixed.
A Control Plane Needs Its Own Domain Model
Tenants are data too. The tenant-management database is the one single-tenant database in the whole platform, and its five entities — Tenant, TenantConnection, TenantFeature, DatabaseGroup, TenantMigrationHistory — carry every decision the rest of the series depends on.
Rich Domain, Honest Stubs
A retrospective on nine DShop services - the order aggregate and checkout saga that genuinely work, sitting next to the discount that only prints, the emails that never send, and a currency guard that guards nothing. Part 15 of Nine Services and a Message Bus.
BuildServiceProvider Nine Times
Each concern in DShop.Common builds a throwaway DI container just to read config - nine per service, atop three coexisting container frameworks and a vendored config parser.
The Class Name Is the Registry Key
Above raw resolution sits a convention layer - an abstract endpoint base class that derives its Key Vault lookup key from its own type name, a template method separating the call from the interpretation, and a generic proxy that routes by name across every endpoint the DI container knows. Part 4 of Service Discovery Without a Service Mesh.
The Test Folder That Lies
Nine DShop services ship a tests folder and only one of them tests anything - a census where five test projects cannot even see the code they claim to cover and the lone unit test asserts a thing that never happens. Part 14 of Nine Services and a Message Bus.
Revoking the Irrevocable
DShop.Common makes a stateless JWT revocable with a Redis deny-list and a per-request round-trip - plus an iat claim in milliseconds and two validators that disagree.
What's Inside a Pact File
An annotated tour of the JSON document Pactify produces - the serializer settings that shape it, the snake_case field inherited from Pact v1, and the unusual decision to ship the consumer's matching options inside the contract itself.