Fränz Friederes

@fraenz.frieder.es

51 Followers 85 Following

Solo Software Engineer at wierk.lu building a SaaS for DMARC monitoring dmarced.eu, deciphering Enigma cryptograms, and chasing sneaker drops, he/him 🏳️‍🌈

Screenshot of a DNS record detail view, showing the TXT DMARC record value, the exact TTL, DNSSEC validation status, and the time range during which the record was observed.

The audience and stage of the Nordic.js conference, in blue/pink mood

Diagram titled “My responsibilities with a serverless stack” showing a vertical stack of labeled boxes. Only “Application code” is left unmarked, indicating it’s the developer’s responsibility. The other layers “Operating system,” “Virtualization,” “Physical hardware,” and “Data center access control” are each crossed out, illustrating that these are not managed by the developer when using a serverless setup.

A black-gray British Shorthair sitting on a wooden deck chaire outside in the garden.

Pamela Downing 20 years © morganfourman.com

Screenshot of a database table showing team data with two ID columns: privateId, a sequential number, and id, a prefixed Nano ID like tm_imswzl4d93om used externally. The table includes names like Alice, Bob, and Wierk, and is ordered by privateId.

Screenshot of Stripe’s product metadata editor, showing plan limits such as data retention days, max active domains, and email volume for a SaaS subscription.

Diagram showing a strict API boundary between a frontend (Next.js on Vercel) and a backend (AWS SAM on Lambda), connected via a REST API. The frontend moves fast, focuses on UI iteration, has abstracted infrastructure, no access to session cookies, uses push-to-deploy, and acts as just another API consumer. The backend moves slower, is more deliberate, fully controlled, manages HTTP-only session cookies, and uses manual deployments.

Postgres database table showing enriched IP address ranges with metadata including country code, ASN, and network owner name. Used to provide human-readable IP context in DMARC reports.

macOS lock screen showing the retro Macintosh screensaver with a pixelated purple design

A diagram showing the architecture of a DMARC processing pipeline built with AWS components: A component labeled “DmarcSesReceiptRule” represents an SES rule that receives email. It connects to an “S3 bucket” labeled “DmarcInboxBucket” where raw email is stored. This inbox bucket triggers a “Lambda function” labeled “DmarcProcessingFunction” to process each email. Processed reports are written to a final “S3 bucket” labeled “DmarcDataLakeBucket” for long-term storage.

Table showing four rows of email traffic data. Each row includes a sparkline visualizing the trend of email volume over time, along with total volume numbers and colored indicators showing recent increases or decreases.

Screenshot of a Trade Republic email asking how likely I am to recommend Trade Republic to a friend or colleague listing buttons labelled 0 to 10 below it.

A screenshot of Visual Studio Code with the file "en-IE.json" open. It contains hierarchical objects with keys and English messages for "domainReport" and "loginVerification" emails.

Screenshot of dmarced’s email traffic categories in action. The report is split into three sections: ‘Delivered and fully verified,’ ‘Delivered after being forwarded,’ and ‘Delivered but lacking verification.’ Each section includes a table listing email sources, the number of emails, and trends compared to the previous reporting period, such as increases or decreases in email volume.